Archive Magazine CD 1995/Archive Magazine CD 1995.iso/text/magazine/volume_05/issue_04

Text File | 1995-06-25 | 213KB | 4,746 lines

Archimedes − The DTP machine
5.4
Outside the Acorn world, if you mention desktop publishing, people’s
thoughts automatically go to Apple Mac. Yes, you can do DTP on lots of
other machines, but the Mac is the benchmark against which all others
are judged.
5.4
Having been involved with the Apple Mac for over five years, I am well
aware of the Macs’ DTP capabilities. I know what we are up against, but
I feel very strongly that Archimedes computers, software and peri
pherals, could challenge the dominance of the Mac, at least in the UK.
5.4
I say “could challenge” because it’s one thing to know that £4,000 can
buy you an A5000 DTP system equivalent to a Mac system costing over
£10,000, but it’s another thing to get the message across to people who
have never even heard of Acorn, let alone the A5000.
5.4
Norwich Computer Services is only a very small company but we are doing
what we can to spread the gospel of Archimedes DTP. We are currently
producing a small, free A5 booklet entitled “Desktop Publishing on
Archimedes Computers”. If you’re thinking of going into DTP yourself, I
think you would find the booklet helpful. Also, if you would like to use
any of these booklets to give to others to help spread the word, just
tell us and we’ll send you as many as you can use. It’s advertising for
us, so we’re happy to stand the cost.
5.4
Acorn DTP System
5.4
Acorn are going to be doing their part to spread the Archimedes DTP
gospel by producing and marketing a complete DTP system. This will be
based round the A540 with a Laser Direct HiRes8 printer and Impression
(what else?!) but full details have not yet been released.
5.4
Best wishes for 1992!
5.4
All the staff at Norwich Computer Services join together to wish you all
the very best for the New Year. We hope that 1992 will be a very good
year for you all.
5.4
      Adrian, Ali, Ray, Roger, Paul & Sue.
5.4

5.4
Products Available
5.4
•    A5000’s back in stock − The stock situation on A5000’s seems to change
weekly. Anyway, as I write (2/1/92) we have both A5000 Learning Curves
and straight A5000’s without Learning Curves in stock. No, sorry, not
the A5000 1FD (1M no hard drive version). We have some on order but we
gather that Acorn are not releasing any for the foreseeable future. As
far as we know, Acorn are only supplying them to VARs (Value Added
Resellers), i.e. companies who buy them and add their own software and
hardware etc which they then sell as a complete system.
5.4
We can help you in customising by  (a) offering alternative monitors
e.g. we supply an Eizo 9060S for £200 above the price including the
Acorn multi-sync (b) offering a second additional internal 100M IDE
drive for £380 (having tested that it is compatible with the Acorn IDE
interface − see comments on page 12) and (c) offering £100 in part
exchange on a Conner 40M IDE drive (i.e. replace the 40M with 100M for
£280) but this offer is at our discretion as we don’t want to end up
with lots of 40M IDE’s we can’t get rid of. Also, we can offer (subject
to availability) a second additional internal 40M IDE drive for £120
(the extra is to account for extra cabling and labour) but I won’t put
this on the Price List − it’s complicated enough already. If you are
interested, give us a ring. So, based on a Learning Curve pack, here are
the combined prices...
5.4
    2M      4M      8M
5.4
A5000 (40M)    £1799    £1929
£2399
5.4
A5000 (40M + 40M)    £1919    £2049
£2519
5.4
A5000 (100M)    £2079    £2209
£2679
5.4
A5000 (40M + 100M)    £2179
£2309    £2779
5.4
then add £200 if you want an Eizo 9060S instead of an Acorn m/s or £270
if you would prefer a Taxan 795 or £460 for an Eizo 9070 (16“) or £910
if you want an Eizo T560i 17” Trinitron (see below for details).
5.4
•    A5000 Technical reference manuals − Acorn have produced a technical
reference manual for the A5000 which consists of about 40 pages of text
plus 9 A1-size drawings including assembly diagrams, circuit diagrams
and component layouts. The price is £65 from Acorn or £62 through
Archive. (They are in stock now.)
5.4
•    Atomwide 200M SCSI drives − The 200M Pro Quantum drive mechanisms that
Oak Solutions use in their High Speed drives are now available from
Atomwide in their own boxes. I am using one on my A540 and it is
noticeably faster than the 100M Conner in the A540 itself. (1350 kbytes/
sec cf 790 k/sec) The prices, through Archive, are £705 for an internal
drive and £795 for an external. (These prices are without podule.)
5.4
•    Careware and Shareware Four new discs of PD software are available
this month:
5.4
Careware 15 is ‘religious’ clip art: dove, lion, lamb, fish, sheep,
spring lamb, whale, holly, Santa, snowman, snowflakes, tree, 14
different crosses, handshake, open hands, praying hands, anchor, bible,
censor, crown of thorns, handbell, pulpit, scroll, baptism, boy praying,
person kneeling, nun, bishop, singers, robed figure, Bede, Coverdale,
Tyndale, Wycliffe, church yard, lighthouse, Westminster, helmet, inri
scroll, signpost.
5.4
Careware 16 has clip art images from ILEA designed to promote “positive
images” of people of different races, gender, ages and disabilities.
5.4
Shareware 42 has twilight, sun and moon rise/set calculator, gravity
simulator, various blank sheets for personal organiser, clipart
(includes typewriter plus sprites of car, crash, masks, town crier,
tanks, policeman, poundsign, scissors, scouts symbol, world map),
desktop Pacman game, draughts, Escape from Exeria, Guardians of the
Labyrinth, various desktop patterns, wall paper designer(?), address
label database, desktop backdrop, “approximate” clock, current directory
set utility.
5.4
Shareware 43 is a DBK raytracer with demo files. (Members’ prices are £6
for Careware and £3 for Shareware.)
5.4
•    ChartWell is a sophisticated graph and chart package from Risc
Developments. It provides horizontal and vertical bar charts, line
graphs, pie charts, scatter diagrams and polar plots. £29.95 from Risc
Developments Ltd. (Although it has the same address as Beebug Ltd, they
ask us to make clear that this is a separate company.)
5.4
•    Cumana SCSI interfaces − Cumana have now released three SCSI inter
faces: 16 bit internal for A310/400/5000, 16 bit external for A3000 and
8 bit internal for A3000. The prices are £151, £161 and £130 respec
tively (+VAT). One major plus of these interfaces is that they include
CDFS so you won’t need to pay for an upgrade to the software if you buy
a CD-ROM system. (We have one of each for evaluation, so we hope to
check whether, for instance, they will work with Computer Concepts’
ScanLight Professional. A report will, hopefully, appear next month.)
5.4
•    Eizo T560i monitor − If you want a really top-notch 17“ monitor for
the Archimedes, this is it! It’s a Trinitron tube with 0.26mm dot pitch
which, on a 17” monitor is very fine and it has the advantage of the
flat Trinitron tube. However, the best part about it is that it is
(extremely) intelligent. It is microprocessor controlled so what you do
is to teach it any new mode you want to use. With a push button control,
you can adjust brightness, H size, V size, H position, V position, side
pin (to cut out pincushion distortion), trapezoidal (again alters the
shape of the screen), H static convergence and V static convergence.
Then having adjusted each of those parameters for that particular screen
mode, it remembers them so that when the same signal appears again, the
monitor says, “Ah, I know that mode” and displays it exactly as you had
adjusted it. Then you can switch to another mode you use commonly and
adjust that to get optimum use of the screen.
5.4
The price? Oh, yes, the price... “only” £1240 inc VAT and carriage! Is
it worth it? Well, I’m using one at the moment and it is certainly very
impressive but for me personally, the extra £450 over the Eizo 9070
would be difficult to justify. This is partly because I use the same
mode 99.9% of the time, so having to re-adjust the screen when going
from mode to mode doesn’t worry me. Also, the T560i, like the Taxan 875,
can’t quite cope with mode 102 (1152×448) and so you have to use mode
106 (1088×448) i.e. 6% fewer dots across the screen. Still, if you
change modes a lot and especially if you want to use the same monitor on
different types of computer and want the extra resolution then the T560i
is for you.
5.4
(I’ve got one of the new Microvitec 20“ autoscan (microprocessor-
controlled) monitors on order, so I’ll let you know how I get on with
that − the Archive price is likely to be £1590.)
5.4
•    Flight Sim Toolkit − Simis Ltd have released a flight simulator editor
for just £44.95 inc VAT or £42 through Archive. It allows you to produce
your own flight simulations by using a ground editor, a 3D shape editor
for objects like trucks, planes, etc, an aircraft model editor which
controls the plane’s flying characteristics and, finally, a cockpit
editor.
5.4
•    Freddy Teddy is back − Topologika have released a third in the Freddy
Teddy series for infants. This time Freddy Teddy is in The Playground.
The Playground is £29.95 +VAT, which includes a free site licence, or
£32 through Archive.
5.4
•    Hard Disc Companion II − Risc Developments’ update of their hard disc
backup program is now available for £45 +VAT. It is faster than the
original and has many new features including backup to hard drive as an
alternative to floppies, backup certain filetypes only or ignore certain
filetypes. It can also be used for backing up networks. (Their adver
tisements claim that it is “the best selling hard disc backup program”
but I doubt whether, at £45+VAT, they could possibly have sold as many
as Shareware 36 which, at £3, has a hard disc backup as one of its many
programs and utilities.)
5.4
•    Hearsay II − Beebug’s new comms package is now fully multi-tasking.
£75+VAT from Beebug or £82 through Archive. See the review on page 34
for more details.
5.4
•    Morley prices drop − The Morley SCSI disc drives have dropped in price
and the 40M drives have been replaced by 50M. The new prices are given
on the price list but are summarised here in comparison with various
other drives. Atomwide (AW) and Frog drives come without podule and so
can be paired with Oak, Morley uncached (Mu/c) or Morley cached (Mc)
podules. The figures in italic are high speed drives.
5.4
EXTERNAL drives (with podule)
5.4
    WW    HS    Frog    Frog    Frog    AW
AW    AW    Mrly    Mrly
5.4
            Oak    Mu/c    Mc    Oak
Mu/c    Mc    Mu/c    Mc
5.4
45M    500        520    460    510
5.4
50M        560
620    560    610    435    485
5.4
65M            550    490    540
5.4
80M    565
5.4
100M    695    760    620    560    610
790    730    780    570    620
5.4
200M    1060    1180    870    810
860    995    935    985
5.4
300M        2100    1290    1230
1280
5.4
640M        2850    1690    1630
1680
5.4
1000M            2290    2230    2280
5.4

5.4
INTERNAL drives (with podule)
5.4
    WW    HS    Frog    Frog    Frog    AW
AW    AW    Mrly    Mrly
5.4
            Oak    Mu/c    Mc    Oak
Mu/c    Mc    Mu/c    Mc
5.4
45M    405        490    430    480
5.4
50M        470
535    475    525    360    410
5.4
65M            520    460    510
5.4
80M    450
5.4
100M    570    660    590    530    580
700    640    690    570    620
5.4
200M    995    1090    840    780
830    905    845    895
5.4
•    Prophet − Apricote Studio’s combined Stock Control, Invoicing and
Accounts program is called “Prophet”. (I’m sure there is a good reason
for the name though it escapes me at the moment unless it relates to the
biblical quote, “and behold, he shall make a great prophet”!) The price
is £169.95 from Apricote or £157 through Archive. If you already have
either Account Book or Invoice Program, you can get the full package for
£69.95 from Apricote and if you have both, it will cost you just £39.95.
5.4
•    ScanLight prices drop − With the coming of the ScanLight Professional,
Computer Concepts have dropped the price of the A4 Scanlight to £399
+VAT with sheetfeeder and £299 without. (Archive prices are £435 and
£325 respectively.) They have also dropped the Price of ScanLight Junior
(not the 256 version) to £129 +VAT or £140 through Archive. There is
also an upgrade to the software which offers improved grey-map control
using a bezier curve along with simpler brightness and contrast
controls. It now also includes image enhancement functions such as
sharpening. CC claim that ScanLight is the only scanner software that
offers realtime greyscale dithering of images to produce near photo
graphic on-screen representations. This software upgrade will be
available to all existing ScanLight owners free of charge.
5.4
N.B. ScanLight Professional only works reliably with certain SCSI
controller boards − Acorn, Morley and Lingenuity. In some cases, it
works OK with the Oak SCSI board and CC are actively trying to get it so
that it works consistently with Oak boards. However, they are NOT
working on any others because they are not Acorn compatible. It does NOT
work with the TechnoSCSI board. ScanLight Professional is available
through Archive at £970 inc VAT or £1070 with a SCSI podule.
5.4
•    ScreenTurtle − Topologika’s latest release is a “friendly” turtle
graphics program called ScreenTurtle. It uses a parser so that if it
doesn’t know the command you type in, it guesses! It has on-screen
interactive help and it ‘ticks’ commands that it likes. As well as the
standard Logo features, it has absolute directions, “BEARING” and
“HEADING”, as well as positive and negative Cartesian co-ordinates. To
extend turtle graphics into the realm of art, there is a turtle
generated colour FILL as well as a mouse controlled PAINT. The price is
£39.95 +VAT from Topologika or £43 through Archive.
5.4
•    Software from Germany − There is a thriving Archimedes software
industry in Germany. One example of this is Klein Computers from
Ruesselsheim, near Frankfurt. They have developed five items of
Archimedes software: MouseRecorder (£25) for creation of demos, BestForm
(£49) which is a formula-editor for DTP, 2D/3D FunctionPlotter (£20)
which includes Drawfile output, G-Draft (£49) a CAD package and HD-
Backup (£10) which includes other disc utilities. All these prices
exclude VAT which, presumably, would be charged by customs on entry to
UK, though small items are often ignored, I think. Klein computers would
prefer a Eurocheque written in DM (but who, in the UK, uses Eurocheques?
even in 1992!). (A demo of BestForm appears on the monthly program
disc.)
5.4
•    TinyLogo/TinyDraw is now available from Topologika in a new version
(at the same price of £29.95 +VAT or £32 through Archive) which includes
adjustable shapes, colours preserved on export, undo, error checking, 3
pencil thicknesses etc. An upgrade for existing users is available for
£5 +VAT (+ £1.50 p&p) if you send back your old disc plus proof of
purchase to Topologika (not to Archive).
5.4
•    !Transfer is a new utility which will allow you to transfer text from
any icon in any RISC-OS application to any other. This has many
applications − for example, you could grab a name and address from a
database and drag it straight into a wordprocessor. !Transfer is just
£8.95 from Apricote Studios or £8 through Archive.
5.4
•    Typestudio is Risc Developments new text effects package which allows
you to draw and edit text, save in Draw or internal formats, print using
RISC-OS drivers and add or remove effects. These effects include
moulding to shapes, flowing along lines, shadowing, slanting, 3D and
mirroring. All this for just £45 +VAT.
5.4
Review software received...
5.4
We have received review copies of the following software and hardware:
CalcSheet (needs a second reviewer to act as “referee”), Landmarks
Victorians and RainForest also need a “referee”. Converta-Key, Fun &
Games, !BasShrink, Holed Out Compendium, SmArt Graphics System.  A
5.4

5.4
Government Health Warning − Reading this could seriously affect your
spiritual health.
5.4
How many New Year’s Resolutions did you make this year? The New Year is
a great opportunity for making a new start, turning over a new leaf etc,
etc. The trouble is, we all know what happens... within a few days (or
hours?) we slip back into whatever it was we decided we would avoid.
Hmmm!
5.4
The basic problem is that although we know what we ought to do, it’s
just such jolly hard work trying to do it. Even though we know in theory
that, in the long run, things will be better for us and for those around
us if we take a particular course of action, we so often go for the
easiest way in the short term − and suffer the consequences later.
5.4
This is where the Christian message is such good news. Firstly, it gives
us a motive for doing what is right − when we discover how much God
loves us and we grow to love him too, we want to do things to please
him. Secondly, if you think that Christians seem to have an inner
strength, you’re absolutely right! It sounds fantastic, but Jesus said
he would live in us and Christians will testify that, with God living in
them, they can do things that would be impossible without God’s
strength.
5.4
I pray that, in 1992, you will discover more of the love and power of
God that is found in Jesus Christ!
5.4

5.4

5.4
Norwich Computer Services 96a Vauxhall Street, Norwich, NR2 2SD. 0603-
766592 (764011)
5.4

5.4
4th Dimension     P.O. Box 4444, Sheffield. (0742−700661)
5.4
Abacus Training    29 Okus Grove, Upper Stratton, Swindon, Wilts, SN2
6QA.
5.4
Academic Software    Sourby Old Farm, Timble, Otley, Yorks, LS21 2PW.
(0943−88−628)
5.4
Acorn Direct    13 Dennington Road, Wellingborough, Northants, NN8 2RL.
5.4
Acorn Computers Ltd    Fulbourn
Road, Cherry Hinton, Cambridge, CB1 4JN. (0223−245200) (210685)
5.4
Acorn Training Centre    Unit 5,
Cambridge Technopark, 645 Newmarket Road, Cambridge CB5 8PB.
(0223−214411)
5.4
Ace Computing    27 Victoria Road, Cambridge, CB4 3BW. (0223−322559)
(69180)
5.4
Aleph One Ltd    The Old Courthouse, Bottisham, Cambridge, CB5 9BA.
(0223−811679) (812713)
5.4
Apricote Studios    2 Purls Bridge Farm, Manea, Cambridgeshire, PE15 0ND.
(035−478−432)
5.4
Arxe Systems Ltd    P.O.Box 898, Forest Gate, London E7 9RG. (081−534−1198
evenings)
5.4
Atomwide Ltd    23 The Greenway, Orpington, Kent, BR5 2AY. (0689−838852)
(896088)
5.4
Baildon Electronics    1 Fyfe
Crescent, Baildon, Shipley, W Yorks BD17 6DR. (0274−580519) (531626)
5.4
Base5 (p22)    PO Box 378, Woking, Surrey GU21 4DF.
5.4
Beebug Ltd    117 Hatfield Road, St Albans, Herts, AL1 4JS. (0727−40303)
(60263)
5.4
Cambridge International Software      Unit 2a,
Essex Road, London, N1 3QP. (071−226−3340) (226−3408)
5.4
Chalksoft    P.O. Box 49, Spalding, Lincs, PE11 1NZ. (0775−769518)
5.4
CJE Micros    78 Brighton Road, Worthing, W Sussex, BN11 2EN.
(0903−213361)
5.4
Clares Micro Supplies    98 Mid
dlewich Road, Rudheath, Northwich, Cheshire, CW9 7DA. (0606−48511)
(48512)
5.4
Colton Software (p21)    2 Signet
Court, Swanns Road, Cambridge, CB5 8LA. (0223−311881) (312010)
5.4
Computer Concepts (p32/33)    Gaddesden
Place, Hemel Hempstead, Herts, HP2 6EX. (0442−63933) (231632)
5.4
David Pilling    P.O.Box 22, Thornton Cleveleys, Blackpool, FY5 1LR.
5.4
DT Software    13 Northumberland Road, Leamington Spa, Warwickshire, CV32
6HE.
5.4
GL Consulting Ltd    8 Agates Lane, Ashtead, Surrey, KT21 2NF.
(0372−272937) (279362)
5.4
Godders Ware    13 Prestbury Close, Blackpole Village, Worcester, WR4 9XG.
5.4
Irlam Instruments    133 London Road, Staines, Middlesex TW18 4HN.
(0895−811401)
5.4
Klein Computers    Hasslocherstrasse 73, D-6090 Ruesselsheim, Germany.
(010−49−6142−81131) (81256)
5.4
Krisalis Software    Teque House, Mason’s Yard, Downs Row, Moorgate,
Rotherham, S60 2HD. (0709−372290)
5.4
Lingenuity (Lindis)    P.O.Box 10,
Halesworth, Suffolk, IP19 0DX. (0986−85−476) (460)
5.4
Longman-Logotron    124 Cambridge Science Park, Milton Road, Cambridge CB4
4ZS. (0223−425558) (425349)
5.4
LOOKsystems (p7)    47 Goodhale Road, Bowthorpe, Norwich, NR5 9AY.
(0603−764114) (764011)
5.4
Microvitec Ltd    Bolling Road, Bradford, BD4 7TU. (0274−390011)
(734944)
5.4
Minerva Systems    Minerva House, Baring Crescent, Exeter, EX1 1TL.
(0392−437756) (421762)
5.4
Morley Electronics     Morley
House, Norham Road, North Shields, Tyne & Wear, NE29 7TY. (091−257−6355)
(6373)
5.4
Next Technology Ltd    St John’s
Innovation Centre, Cambridge, CB4 4WS. (0223−420222)
5.4
Pedigree Films Ltd    Unit B11,
Trinity Business Centre, 305 Rotherhithe Street, London  SE16 1EY.
(071−231−6137) (237−5776)
5.4
Ray Maidstone (p22)    421
Sprowston Road, Norwich, NR3 4EH. (0603−407060) (417447)
5.4
RISC Developments Ltd    117 Hatfield
Road, St Albans, Herts, AL1 4JS. (0727−40303) (60263)
5.4
Serious Statistical Software    Lynwood,
Benty Heath Lane, Willaston, South Wirral, L64 1SD. (051−327−4268)
5.4
Sherston Software    Swan Barton, Sherston, Malmesbury, Wilts. SN16 0LH.
(0666−840433) (840048)
5.4
Simis Ltd    26 Chittys Walk, Keens Park, Guildford, GU3 3HW. (0483−233048)
(235275)
5.4
Software Solutions    Broadway
House, 149−151 St Neots Road, Hardwick, Cambridge, CB3 7QJ.
(0954−211760) (211760)
5.4
Spacetech (p8)    21 West Wools, Portland, Dorset, DT5 2EA.
(0305−822753)
5.4
Technomatic    468 Church Lane, London, NW9 8UF. (081−205−9558) (0190)
5.4
Topologika (p15)    P.O. Box 39, Stilton, Peterborough, PE7 3RL.
(0733−244682)
5.4
Watford Electronics    250 Lower
High Street, Watford, WD1 2AN. (0923−37774) (33642)
5.4
Word Processing    65 Milldale Crescent, Fordhouses, Wolverhampton, W
Midlands  WV10 6LR.
5.4

5.4

5.4
Computer Concepts
5.4
From 5.3 page 32
5.4

5.4
Computer Concepts
5.4
From 5.3 page 33
5.4

5.4
Hints and Tips
5.4
•    A5000 monitor problem − One problem which various people seem to have
had with the Acorn A5000 monitors is intermittent contact on the mains
cable but the solution is simple. When you plug the power cable into the
monitor, it seems to go in but actually, to get it fully home, you have
to push it very firmly.
5.4
•    Draw files in Impression − Did you know that when using Draw files in
Impression frames, it is possible to “zoom” in on a part you want to
concentrate on and bring it up to “fill the frame”? This means you can,
for example, call up a file of, say, a fruit filled bowl and then choose
the apple to fill the space available in your document or show a group
of cartoon figures and, in the next frame, have a “close up” of one
face. Since Draw files are capable of incredible scaling, their should
be no real loss of detail involved.
5.4
The procedure is simple. Create a frame for the draw file. Open the
directory containing the Draw file. Drag it into the frame in the usual
way. Changing the shape of the frame with its handles using <select>
will “crop” the picture until only the part you require is visible. Then
enlarge the frame using the adjust button on the corner handles. The
cropped picture will “grow” with your mouse movements. (Well, stone me!
I didn’t know that! Please keep sending these “obvious” hints − they are
not obvious to everyone. Ed.)
5.4
Incidentally, don’t try moving a frame containing a Draw file around the
page using the usual method of pointing inside it, holding down <select>
and waiting for the blue lines to appear. If you don’t wait quite long
enough, the graphic moves inside the frame and bang goes your careful
alignment! Instead, hold down <ctrl> when you press <select> and the
frame can be moved safely and immediately. Kevin Beales, Shropshire.
(The latter hint was also sent in by Johannes Thordarson of  Ice
land.)  A
5.4

5.4
Small Ads
5.4
(Small ads for Archimedes and related products are free for subscribers
but we reserve the right to publish all, part or none of the material
you send, as we think fit. i.e. some people don’t know what “small”
means and there are certain things, as you can imagine, that we would
not be prepared to advertise as a matter of principle. Sending small ads
(especially long ones!) on disc is helpful but not essential. Ed)
5.4
•    A310 base unit + 2nd external 3½“ drive and interface (Technomatic)
£600. Microvitec 1451 monitor £150. Phone 081−391−2582 evenings.
5.4
•    Apocalypse £15 o.n.o., Drop Ship £10, StarTrader £6, E-Type £10. Phone
Simon on 0654− 791−671.
5.4
•    Archeffect for FX, manual & disc. Beebug’s serial link & disc. Any
reasonable offers. Phone Stephen on 0843−298902.
5.4
•    Pace Series 4 2400S modem (Hayes V21/23/22/22bis) £130 or part
exchange for Eizo 9060S or similar. Might consider swap for fast 40/50M
ST506 drive. Phone Chris on 0271−850355.
5.4
•    Recent graduate, programmer, keen on Archimedes, very good knowledge
of C, Basic + ARM code, seeks employment, anywhere. Unemployed but very
employable, just what you need. Will send full C.V. on request. Phone
0245−74402.
5.4
•    Serial Port joystick interface £18. Blowpipe £6. inc post. Phone K.
Beales on 0746−862011.
5.4
•    Wanted for A3000 − hard disc (80M +) preferably SCSI, LinCAD or Solid
Tools and CGI Genlock. Contact Neal on 0734−420836.
5.4
•    Wanted for A310 − hard disc plus interface, IFEL bplane, PipeDream,
Impression, Multisync monitor. Phone 0442−67952 eves/weekends.
5.4
•    Wanted − Computer Concepts ROM/RAM podule. Martin Zanders, Snippes
traat 19, 8450, Bredene, Belgium.
5.4
Charity Sales − The following items are available for sale in aid of
charity. PLEASE do not just send money − ring us on 0603−766592 to check
if the items are still available. Thank you.
5.4
(If you have unwanted software or hardware for Archimedes computers you
could donate for charity, please send it in to the Archive office. If
you have larger items where post would be expensive, just send us
details of the item(s) and how the purchaser can get hold of them.)
5.4
Arcade 3 £6, Corruption £5, Acorn DTP £20, Tempest DTP £20, Lemmings
£18, Pacmania £12, Euclid £15, Superior Golf £8, Interdictor 1 £5,
Trivial Pursuit £10, Saloon Cars £19, DiscTree £9.  A
5.4

5.4
Help!!!!
5.4
•    Italian Archimedes needed − Christian Ghezzi is trying to get hold of
a second hand A310 or A410 but is finding it difficult as he lives in
Italy. Can anyone help him? Write to him at Via B. da Urbino 2 − 20035
Lissone (MI), Italy.
5.4
•    PC emulator compatibility − If anyone can tell us of programs that do
or do not work under PC emulator versions 1.6 or 1.7, would they please
send the information to Mike Clinch who has agreed to collate all the
information for us. Please send him as much detail about version numbers
of software and what configuration you were using including the version
of DOS. Mike Clinch, 2 Parkhurst Road, Bexley, Kent, DA5 1AR. (No phone
calls, please.)  A
5.4

5.4
Comment Column
5.4
•    A310 + ARM3  − I have recently had my A310 fitted with a CJE Micros’
ARM3 and a MEMC1a. I thought about it for some time because of the price
and whether it was worth fitting one to my machine (which has a hard
disc and 4 MB of RAM) because the arrival of the A5000 has reduced its
second-hand value further, from about £500 to £200! However, the price
of the upgrade has fallen to £293 and so I took the plunge. (It’s now
down to £225 through Archive. Ed.) I was especially keen to get fonts
cached faster and Draw files drawn faster. I haven’t seen any published
figures for the speed increases for actual documents etc. so I have done
some myself.
5.4
The times in seconds with ARM3 cache off and on are as follows:
5.4
Cache       Fonts   Draw files  Multistore
5.4
Off    31.4    15.8    144
5.4
On    9.2    5.0    71
5.4
Ratio    3.45    3.12    2.04
5.4
All were taken in Mode 78 (a 192k Computer Concepts mode). The speed of
the A310 with cache off is about 10% faster than a plain A310 without
MEMC1a, so the above speed increases of my upgraded machine should be
increased by a further 10% when comparing with a plain A310. The fonts
times are for caching them in RAM in a test Impression file with many
sizes of Trinity and Homerton characters, the RAM font cache of the
Archimedes being cleared before each test. The Draw files were a
miscellany of designs that took a long time to draw. The Multistore test
was a search of an 800-record file. (Indeed, the continuous browse went
too fast to see each record as it whizzed past − I had to turn the ARM3
cache off!) The increase in speed in these tests and in real documents
and various programs is very great indeed, and sufficient to effectively
get rid of the irritating delays while fonts cache and Draw files draw.
5.4
But everything goes faster: sliding across Wimp menus; moving windows;
calling up dialogue boxes; paging documents; loading !PrinterDM and
running Mandelbrot (both much faster), etc. The ARM3 comes with a module
that must be run and can be included in your !Boot file. I recommend the
upgrade.
5.4
One drawback, though, is that some A310s (e.g. mine!) and A540s have a
problem in coping with printing at the high speed of the ARM3. Lines are
split horizontally, in e.g. Paint and Impression. A free modification is
available. In the meantime, if this afflicts you, choose File on
!PrinterDM (reached by clicking <menu> on the !PrinterDM icon) and type
a path and file name. “Print” with the cache on. Then, switch the cache
off, reset !PrinterDM to Parallel (or Serial if it was that before),
drag the new file to the PrinterDM icon and it will print properly.
However, the length of an A4 document saved at 360×360 dots resolution
exceeds the capacity of a floppy, so use your hard disc or reduce the
resolution.)
5.4
I have had two demonstrations of RISC-OS 3 on a friend’s A5000. It
certainly has some nice enhancements but I do not think that it is a
very big improvement on RISC-OS 2. In any case, it is reported that it
will be available for A300 machines in the summer for about £50. (I
heard it was going to be more like £100 but less for education. Ed.) All
this therefore leads me to conclude that you should consider an ARM3
upgrade before exchanging your A300 range machine for an A5000. Steve
Kirkby, Sutton.
5.4
•    A5000 Hard Disc crash − Users of A5000’s (and anyone using RISC-OS 3
on other machines − legally or illegally!) ought to know that we have
had two occurrences now of hard discs being made completely unreadable −
all data lost! We don’t yet know what is causing it but I’ll tell you
the circumstances in which it happened so that (a) you can try and avoid
it happening to you and (b) you can report to us any similar experiences
you have had which might help us to track down the problem.
5.4
In both cases (one was us and the other was one of our contributors) the
map and root directory of the hard disc was over-written with rubbish so
that the system said something like, “I don’t recognise that kind of
disc”. In one case it was an A5000 and the other was an A540 running a
development version of RISC-OS 3. The common factors were that it was a
removable hard drive running on Oak’s SCSI interface (version 1.16
software). We reported the problem to Acorn but their response was that
it was probably a code clash with Oak’s software and that they should
look into it before Acorn would get involved. With holidays and their
move to new premises, Oak haven’t yet responded to our report of the
problem.
5.4
Our only other clue was the, in our case, the drive was OK before we
pressed <ctrl-break> but not afterwards.
5.4
•    A5000 (again) − (We have had another A5000 first impressions report
sent in (no more, please unless you really have something new to add!)
and so I have chopped it down dramatically, leaving only those bits
which I don’t think have been said before. The result may be rather
disjointed but I’d rather do that than waste valuable space repeating
other people’s eulogies. By the way, has anyone got any NEGATIVE things
to say about the A5000? Ed.)
5.4
I really am impressed at how professional the system is in terms of
presentation. If this had been my first computer it would have been so
easy and it certainly beats setting up certain video recorders! Acorn
have achieved a Macintosh-like ‘plug-in and go’ convenience with this
machine (and that is intended to be high praise).
5.4
Tony liked Draw’s interpolation ability and produced this very simple
but effective graphic...
5.4
Here are some bits and pieces which Tony found interesting:
5.4
Filer_OpenDir has been fixed so that it properly processes its argu
ments. There is no longer any need for silly Alias$ variables to make it
work. It also permits a whole host of options about the window’s
appearance and size.
5.4
There are new commands, Filer_Boot and Filer_ Run which, when applied to
applications in an Obey file, prevent the delay of the remainder of the
Obey file until after the application’s termination (more flexible than
DeskTop -file).
5.4
There is, at last, a Mode command.
5.4
The system is supplied with a data compression program called Squash
(yet another LZW implementation) which is simply a front end to a RISC-
OS 3 module, a sign of things to come?
5.4
Configure allows the setting of a PrinterBuffer size − I presume that
this works.
5.4
Clicking <select> on the task manager icon (now an acorn) opens the task
display.
5.4
The Cache command controls the ARM3.
5.4
Draw, Paint etc can have their start-up options customised (so now Draw
can start up with the Selection tool selected!).
5.4
How fast is the A5000? Not breathtakingly so, it must be said. The
following are some comparisons of A5000 and A310 in different modes. The
ARM3‘s ability to cope with higher resolution screen modes is perhaps
the strongest point. (Note that my A310 has a MEMC1a which gives it 10%
more speed − the same as an A3000.) The test used the standard Dhrystone
program as supplied with Acorn’s C compiler and compiled using the
Version 4 compiler. The timings are kDhrystones per second over 100,000
iterations.
5.4
Mode    Size    A310  A5000(1) A5000(2)   Norm.
5.4
0    20k    6.0    6.8    18.6    100%
5.4
12    80k    5.2    6.2    18.1    97%
5.4
15    160k    4.2    5.4    17.2
92%
5.4
28    300k    −     3.7    15.6
84%
5.4
The A5000(1) column is with cache disabled, giving an ARM2 equivalent.
The difference from the A310 presumably being accounted for by the
A5000‘s faster RAM. In the A5000(2) column, the 3× to 4× ARM3 benefit is
as expected. The Norm. column expresses the A5000(2) column normalised
against Mode 0 (=100%). While the A5000(1) column is almost halved (55%)
by the move from Mode 0 to Mode 28 the ARM3 cache holds up 84% perfor
mance − impressive.
5.4
Here are some acknowledged bugs:
5.4
The Squash utility is noted in the Release Notes as having a “rare
problem” causing it to corrupt certain repetitive files. However, this
refers to version 0.26 and my machine came with version 0.28 which
postdates the Release Notes so it may have been fixed.
5.4
A late addition to the Release Notes (which was dated November!)
recommends inhibiting ADFS file buffers via the command...
5.4
Configure ADFSBuffers 0
5.4
to avoid a “slight chance” of data corruption or errors. This will slow
Hard Disc performance on randomly accessed files.
5.4
From experience so far, the system is reasonably robust. I experienced a
(non-repeatable) crash with Maestro and background-processing and have
had slightly odd filer operations on a couple of occasions.
5.4
The jury is still out on the floppy drive on my machine. I have had a
single failure of background backup (not repeatable) and it resolutely
refuses to read the Lemmings disc with which the A310 has no problems in
either drive.
5.4
JP 150 printer − For me this was a simple ‘freebie’. I saw an unimpres
sive printout at the show and thought little more about it. However, on
trying the machine, I have somewhat revised my opinion. The print
quality is actually very good and certainly rivals 24-pin matrix
printers. ‘Near-laser’ quality is an exaggeration and the ink comes out
damp (beware of smudging) but it is certainly very usable with good
blacks and greys. The small size and quiet operation of the printer are
also attractive as is its genuinely clever physical design (the paper
path is almost straight and all the guides fold up into a small box with
no dust-traps).
5.4
Most of the conclusion has already been said elsewhere. The A5000 is
very much the machine Acorn had to build, using as it does all the
‘current’ technology. RISC-OS 3 is good but not as big a step forward as
RISC-OS 2 was over Arthur (RIP). The IDE disc seems fine in practice (I
had wondered whether I would regret not having SCSI).
5.4
For those committed to Acorn machines, this is a well priced, fast and
friendly machine. If you are not committed to Acorn, the same money will
buy a lot of ’386/’486 PC (if you can cope with MS-DOS full time) or a
decent Mac. The sums don’t do justice to the amount of bundled software
and subsequent prices, in the Acorn world. For me, dedicated Macintosh
fan as I am, I wouldn’t have anything else. Tony Still, Bournemouth
5.4
That last comment is more significant, perhaps, than many people will
realise. As an ex-Mac user myself, I am well aware of what Macs can do
and would say that, in terms of raw power, the A5000 is equivalent to
Macs costing at least twice the price. However, Mac adherents are,
generally, extremely loyal and won’t normally hear of anything that
could rival their beloved machines, so when a Mac user says the A5000 is
good, you’d better believe it! Ed.
5.4
•    Fourth Dimension game problems − I noted that the first item in the
‘Products Available’ column in the December issue of Archive is the
!Configure program from Fourth Dimension.
5.4
I think that it would be as well to warn readers that this is only a fix
for lack of memory. I recently wrote to this company asking for guidance
and information about the program ‘Chocks Away’ which ran very satisfac
torily on my 410/1 (upgraded to 2M) until I bought a Taxan 795 monitor
and fitted the accompanying Atomwide VIDC enhancer. Subsequently, all I
got was a broken up picture.
5.4
The reply from Fourth Dimension consisted of a photocopied sheet
representing the accompanying program as being the cure-all for problems
of varying amounts of memory, various hard disc interfaces, ARM2 or
ARM3, plus third party peripherals such as digitizers, sound samplers,
scanners, etc. which may have been fitted.
5.4
I did not feel particularly confident that this was going to be the
answer to my problem (in spite of having been assured by a 4th Dimension
spokesman, at an earlier show, that they had now bought a Taxan 795 and
were investigating this!) but felt that I had nothing to lose, since I
had already saved my configuration on a similar program. The !reconfig
program was run and, as expected, failed to provide an answer to the
broken picture problem. The standard fix at this point had always been
to reboot the machine which salvaged the screen output. Unfortunately,
the result of reconfiguring the machine had been also to reset the
monitor type to 0 (instead of the required type 1), so that it was now
impossible to read the desktop in order to be able to re-run the
!ConSaver. A frantic period of blind mouse pointing/typing ensued before
sanity was restored. So, multisync users should be warned of the
problems facing them if they use this program!
5.4
What I find so infuriating about the whole thing is that the November
issue of the BBC Acorn User carried a cover disc with a demo version of
‘Chocks Away’ which ran without problem on my set-up. On this showing,
people could buy the program and then subsequently have all manner of
troubles. Does this amount to false representation? Stan Haselton,
Abbots Langley
5.4
We normally advise people that if they are keen to be able to play all
games without problems, the Eizo 9060 is really the only multisync that
is fully usable. All the others (except, I think, the Taxan 770) need a
VIDC enhancer and this can cause problems in some modes with some games.
Ed.
5.4
• IDE review − In addition to John Kortink’s remarks in Archive 5.3,
p.11/12, I would like to quote some results of a large test of several
dozen hard disks in a major German (MS-DOS) computer magazine.
5.4
Amongst other things, they also tested a number of pairs of hard disks
which were mechanically identical differing only in their controllers.
Here are the speeds according to Coretest (kbytes/sec):
5.4
    IDE    SCSI
5.4
Fujitsu 134 M    627    633    +1%
5.4
Fujitsu 171 M    627    633    +1%
5.4
Maxtor 120 M    1222    770    −27%
5.4
Quantum 199 M    1311    992    −24%
5.4
WD 207 M    1957    1711    −13%
5.4
I think that these values show quite clearly that one cannot say that
either of the two controller types is definitely faster; the only valid
statement is that in each case that disk will be faster which has the
better controller; apparently IDE for the Archimedes simply is not yet
so far in its development as SCSI. (Could it be that the above tests
were done on 8-bit interfaces? The Archimedes’ 16-bit SCSI does speed
things up significantly. Ed.)
5.4
The future may well bring IDE disks which will leave the existing SCSI
disks standing! Jochen Konietzko, Koeln, Germany
5.4
• IDE review − I have to write and protest at John Kortink’s rather rude
and, I believe, unfair comments in Archive 5.3, p.11/12. He accused the
Editor of bias − but I cannot detect any − only an opinion based on a
reasoned argument. John seems so obsessed with speed comparisons that he
seems not to have noticed the important lack of common standards in IDE
interfaces. I read most of the published Acorn magazines and have
followed the IDE vs SCSI argument for some time. My feeling has been
that SCSI would be a better interface to install de novo, so the article
only confirmed my views.
5.4
I am changing my 440/1 for an A5000 but need a larger hard drive than
the 40M IDE one supplied. My local dealer has agreed to substitute a
200M IDE drive but is having problems getting his Rodime drives to work
with the Acorn interface − which only proves the point. Dr I G Pace,
Stamford.
5.4
•    PD software − Mike Williams (of Beebug Ltd) writes... I was a little
surprised to see the comment of David Holden (Archive 5.3 p43). He
appears to be critical of Beebug for giving away PD discs free of
charge. I thought the principal of PD software was that the software
itself was not charged for but that it was acceptable to make a charge
for the service provided, which is what we normally do. Indeed, we are
sometimes criticised for levying too high a charge, but we do have to
include VAT and we have to account for the time spent on running the
library at normal salary rates. Now we appear to be criticised for
providing some of our PD discs free!
5.4
But surely David Holden is missing the essential point about PD software
in the comments he makes. I thought authors and PD libraries operated
with the intention of making a wide variety of software available as
freely and cheaply as possible.
5.4
Perhaps you would like to comment on David Holden’s assertions.
5.4
Mike Williams, Beebug (aka Risc Developments Ltd.)
5.4
As far as I am concerned, both David and Mike have missed the point!
Yes, the intent of PD software is to get it distributed as widely and
cheaply as possible but without using it for “commercial gain”. Now, you
don’t have to actually charge money for something to get commercial gain
from it. The question is, “Why are Beebug offering 10 free discs of PD
software with every A5000?”.  If they are doing it out of the goodness
of their hearts to make PD freely available then that is very commend
able. If, however, they are offering the PD discs in order to persuade
people to buy A5000’s from them rather than from someone else, then they
are using the PD authors’ work for their own commercial gain.
5.4
If Beebug really feel that they are making money on their PD software
and want to give some away why don’t they give a free PD disc to each of
their subscribers as Archive did some while ago?
5.4
Also, if Mike wants to talk about the pricing of PD discs, can he really
justify £4 +VAT for each disc? We started off the Archimedes PD movement
nearly four years ago selling discs at £3 each (including VAT) and the
price has never gone up. We too have to pay “normal salary rates” to our
PD librarian. If we charged £4.00 +VAT each, we’d be making, almost £2
profit per disc. If you multiply that by the 10,000 or so PD discs we
sell each year, we could afford a FULL TIME librarian! Ed.  A
5.4

5.4
Phases #2
5.4
Doug Weller
5.4
Phases #2 is the second stage of Northwest SEMERC’s simple word
processor written for teachers of children with special educational
needs. It is called Phases simply because it is being written in phases,
each an upgrade of the one before. It can be used in a variety of ways.
It is a simple word processor comparable with Prompt/Writer or Stylus
for the BBC. It can be used with two columns, graphics and different
print sizes to provide basic DTP, and can have fixed graphics with a
fixed text area to allow it to be used like Caption.
5.4
Using Phases
5.4
Using Phases as a simple WP is very straightforward; double click on the
!Phases icon and the program loads. Then simply click at the Phases icon
on the icon bar and you get a word-processor screen (one size only).
Position the mouse pointer and you can start writing. Press the menu
button and a very simple menu appears, allowing you to save, change the
letter size, the font, print, create a note pad or go to the tool box.
Some of these functions (e.g. letter size) can be accessed through
function keys, and a keystrip is provided. Phases operates in the
current screen mode.
5.4
Fonts
5.4
Five fonts are provided; Ghost, Joined, Jotter (a bit like Homerton)
Jotter Oblique and Script. These can be applied to separate lines or
paragraphs, but not to areas within them. Likewise, any of the six font
sizes (illustrated on the menu in full size) can be applied to any
paragraph or separate line.
5.4
The notepad
5.4
This is just what it says; an area in which notes or ideas can be
stored, and which is saved with the main work. Its most likely use is by
the teacher, for ideas, questions, story starters, etc. The notepad can
be printed out separately from the main screen.
5.4
Screens
5.4
From the toolbox, three screens can be chosen; one column, two columns,
or Front Page, which provides two top lines, one for a large size
heading and the other for the date, price, etc. Below these the page is
set to two columns. This can be very useful in allowing children to do
‘newspaper’ pages for topic work, etc.
5.4
Pictures & graphics
5.4
Ten pictures, up to a maximum of 160k, can be used in any Phases
document, in either !Draw or Paint format. These can be dragged into a
document and then moved or resized. The Toolbox offers a ‘Picture+’
option, which allows copying of a selected picture, for instance to
create a border. Pictures (or text) can be deleted from the Toolbox
menu.
5.4
Saving work and deleting files
5.4
Phases files are saved in the standard fashion, by typing the file name
into a Save as: window and then dragging the icon into a Work directory.
Pressing <F8> provides a simpler method of saving − a window appears
into which the file name can be typed, after which pressing <return> or
clicking on an OK box saves the document in the work folder. Documents
are saved into up to three sub-directories, so to delete files pressing
<menu> over the Phases icon provides a delete files option which can be
used to delete all files associated with a particular document.
Documents can also be saved as ASCII files for importation into other
programs.
5.4
The Designer
5.4
This is Phases’ most powerful feature, allowing the construction of
documents with fixed font types, letter size, page colour, pictures,
etc. For labelling map or filling in forms created in Designer, etc.,
wordwrap can be turned off. Borders can also easily be created within
Designer.
5.4
Printing
5.4
Printing is done from a menu using the normal RISC-OS printer drivers.
The menu allows selected pages to be printed or all pages, and when
using a colour printer, allows the background colour to be omitted.
5.4
Extras
5.4
Phases comes supplied with a work disc with various pictures and ideas
(animals, space travel, transport, a cheque completion exercise, etc.
The Northwest SEMERC has also created a number of supplementary
packages, including a disc with 14 very nice borders. These borders can
be changed easily using the Designer to make smaller borders, or to
change the page, paper and text colours when loaded.
5.4
The Very Hungry Caterpillar
5.4
This supplementary package is based on Eric Carle’s popular picture
book, It contains two concept keyboard overlays and files for each page
of the book. Each Phases file has the appropriate pictures (‘fixed’
using the Designer) and an associated notepad with words the child might
want to use. The pictures are also provided as separate sprites which
could be used in stories,
5.4
Clip Art Disc #1
5.4
This disc includes sprites of flags (b&w and colour), maps, arrows and
pointing hands for use in Phases; very useful indeed if you are short of
clip art.
5.4
Christmas Disc
5.4
Obviously, this is a disc full of Christmas ideas! Story overlays, some
lovely borders, a variety of secular Christmas sprites and enough
sprites to do a fully illustrated version of the nativity are on this
disc. Also included is a letter page for children to use to write to
Santa! An added bonus is some lovely illuminated letter pictures − large
red capitals decorated with snow and holly.
5.4
Summary
5.4
This is a very useful package for young children or older children with
special educational needs. Its price makes it easily affordable. This
very advantage could be a disadvantage if it were seen as a substitute
for a fully fledged word processor such as Pendown or Impression II,
with their search and replace facilities, adjustable page size, spelling
checkers, etc.  Further ‘phases’, however, promise block cut and replace
and the ability to produce some nice cloze procedures. I have only one
niggle about the program, and that is the fact that your !Fonts
directory must include the Jotter font. I couldn’t find this mentioned
in the manual and it took me a while to find out why !Phases kept giving
me an ‘illegal window handle’ message when I tried to load it using my
ordinary !Fonts directory.
5.4
Phases#2 costs £15. Additional discs (Borders, Clip Art, The Very Hungry
Caterpillar, Christmas Disc) each  cost £7.50.  A
5.4

5.4
Topologika
5.4
New
5.4

5.4
Oak SOlutions
5.4
From 5.4 page 6
5.4

5.4
Designer Fractals
5.4
Robert Chrismas
5.4
There are many programs around now which draw fractals. Part of the
fascination of these programs is that the program and data do not seem
to give any indication of the appearance of the fractal. It is fun to
see an unexpected pattern ‘emerging’ from a few fairly simple lines of
code. With a computer, it is easy to produce the picture if you have the
program. However, it is quite a different problem to look at a fractal
and be able to write a program to produce it on your computer screen.
This article will explain how to create ‘designer fractals’.
5.4
More reflective, and perhaps more mathematically inclined, readers may
have paused at the start of this article and thought ‘well I’ve seen
some things called fractals, but I’m not at all sure what one is’. You
may be encouraged by this quotation from the book ‘Fractals Everywhere’,
by the mathematician Michael Barnsley: ‘Fractals are not defined by a
short legalistic statement, but by the many pictures and contexts which
refer to them.’
5.4
Michael Barnsley’s Collage Theorem provides the key to producing our own
fractal designs. In fact, the collage theorem allows us to create
fractals which are ‘close’ to any shape at all. Here we will concentrate
on creating 2D fractals which can be defined by small sets of ‘simple’
transformations.
5.4
Affine transformations
5.4
Affine transformations can stretch, squeeze, rotate, mirror and also
move a shape but they cannot bend or tear it. An affine transformation
(in 2D) can be described with just six numbers. For each point x, y we
calculate a new point x1, y1 as follows:
5.4
x1 = ax + by + e    y1 = cx + dy + f
5.4
Take the co-ordinates of a simple shape and any six values a,b,c,d,e,f,
calculate a new set of co-ordinates using the equations above, plot the
new co-ordinates on squared paper and join up the dots. The shape has
been transformed. One nice thing about affine transformations is that
straight lines stay straight so you only need to work out where the
corners are. If you like, you can take a point somewhere on a line and
transform it just to make sure it ends up on the transformed line.
Likewise points inside the shape stay inside.
5.4
The !Draw program can perform affine transformations on selected
objects, but copying some affine transformations in !Draw requires
careful combination of rotation and enlargement (or reduction) because
in !Draw shapes can only be squashed along the x and y axes.
5.4
Similitudes
5.4
If we restrict a, b, c, d so that
5.4
a = r cos q,  b = − r sin q  c = r sin q  d = r cos q
5.4
the transformation can only move, rotate and reduce or enlarge the
shape. All the angles must stay the same. In fact, the transformation
will enlarge the shape by a factor r and rotate it by an angle q.
5.4
If we use
5.4
a = r cos q   b = r sin q  c = r sin q  d = − r cos q
5.4
then the same applies but we also mirror the shape.
5.4
It is comparatively easy to find the values a, b, c, d, for a similitude
because we can measure the enlargement (r) and the rotation (t). From
these it is easy to calculate the required values. The values e and f
simply move the shape across and up.
5.4
The collage theorem
5.4
The collage theorem says that we can define a fractal ‘close to’ a given
shape by finding a set of transformations of the shape which just cover
the shape. The transformations, which must all reduce the size of the
shape, can overlap.
5.4
Barnsley gives two algorithms for producing fractals described by a set
of transformations. The ‘Random Iteration Algorithm’ is described here.
It takes any point within the fractal and applies one of the transforma
tions (chosen at random) to it. The new point must also lie within the
fractal because the transformation maps the whole fractal onto part of
itself. so the new point is plotted and the process is repeated. This
should take an infinite time to fill in the whole shape, but since
computer pixels are of finite size, a reasonable approximation to the
fractal can be produced in no more than a long time.
5.4
Since it can be hard to find a point within the fractal to start with,
you can start with any point and do about ten iterations before plotting
any points. (Not very rigorous, but it works.)
5.4
The program
5.4
 10 REM >FractalIt3
5.4
 20 REM Robert Chrismas
5.4
 30 REM 19911116
5.4
 40 :
5.4
 50 MODE 0:REM MODE 18 for multisync
5.4
 60 PRINT “Computing Fractals from Iterated Function systems”
5.4
 70 PRINT “======================== =========================”
5.4
 80 PRINT ‘“From an idea in ‘Fractals Everywhere’ by
5.4
 Michael Barnsley”
5.4
 90 PRINT ‘“This program uses the ‘Random Iteration Algorithm described
on p86.“
5.4
100 PRINT ‘“The data lines define a number of sets.”
5.4
110 :
5.4
120 PROCpause
5.4
130 CLS
5.4
140 :
5.4
150 max_dim% = 20
5.4
160 DIM a(max_dim%), b(max_dim%), c(max_dim%), d(max_dim%)
5.4
170 DIM e(max_dim%), f(max_dim%), p(max_dim%)
5.4
180 :
5.4
190 REM Select the right data lines
5.4
200 set% = 1
5.4
210 REPEAT
5.4
220 READ d$
5.4
230 UNTIL d$ = “%”+STR$(set%)
5.4
240 :
5.4
250 READ description$,max_equation%
5.4
260 READ xf,xc,yf,yc : REM transform to screen co-ords
5.4
270 FOR c% = 0 TO max_equation%-1
5.4
280 READ a(c%), b(c%), c(c%), d(c%), e(c%), f(c%), p(c%)
5.4
290 IF c%>0 THEN p(c%)=p(c%-1)+p(c%)
5.4
300 PRINT p(c%)
5.4
310 NEXT c%
5.4
320 REM Next line may suffer from rounding errors, use integers?
5.4
330 IF ABS(p(max_equation%-1)-1)> 0.00001 THEN PRINT“Probabilities don’t
add up to 1”:STOP
5.4
340 :
5.4
360 CLS
5.4
370 PRINT description$
5.4
380 x=0.5: y=0.5: c% = 0
5.4
381 REM q% = equation number
5.4
390 REPEAT
5.4
410 r=RND(1)
5.4
420 q% = -1
5.4
430 REPEAT
5.4
440 q% = q% + 1
5.4
450 UNTIL p(q%)>r
5.4
460 xn=a(q%)*x+b(q%)*y+e(q%)
5.4
470 yn=c(q%)*x+d(q%)*y+f(q%)
5.4
480 x=xn:y=yn
5.4
490 c% = c% + 1
5.4
500 IF c% > 100 THEN POINT x*xf+xc, y*yf+yc
5.4
510 UNTIL INKEY(0)<>-1
5.4
512 *SCREENSAVE fractalsc
5.4
520 END
5.4
530 :
5.4
540 DEF PROCpause
5.4
550 PRINT“Press SPACE”
5.4
560 *FX 15
5.4
570 REPEAT
5.4
580 UNTIL GET$ = “ ”
5.4
590 ENDPROC
5.4
 600 :
5.4
 610 DATA %1
5.4
 620 DATA Sierpinski Triangle,3
5.4
 630 DATA 10, 0, 10, 0
5.4
 640 DATA 0.5, 0, 0, 0.5, 0, 0, 0.33
5.4
 650 DATA 0.5, 0, 0, 0.5, 0,50, 0.33
5.4
 660 DATA 0.5, 0, 0, 0.5, 50,50,0.34
5.4
 670 :
5.4
1150 DATA %2
5.4
1160 DATA “Sea Horse”,2
5.4
1170 DATA 500,500,500,300
5.4
1180 DATA 0.46,-0.4,0.4,0.46,0.4, −0.2,0.5
5.4
1190 DATA 0.46,-0.4,0.4,0.46,0.0, 0.7,0.5
5.4
Notes on the program
5.4
The program could be tightened up a bit, but I am afraid that once I got
it working, I was too interested in producing fractals to do so.
5.4
For better resolution, you can divert the output to a massive sprite. A
full description of the method would make this (already lengthy) article
far too long.
5.4
You can include any number of fractals in the same program. The data
lines have the following format:
5.4
DATA %<Fractal Number>
5.4
DATA <Name>,<Number of equations>
5.4
DATA <X scale>,<X displacement>,
5.4
<Y scale>,<Y displacement>
5.4
Then as many equation lines as required:
5.4
DATA <a>,<b>,<c>,<d>,<e>,<f>, <probability>
5.4
The ‘Fractal Number’ should be different for each fractal. The value of
‘set%’ (line 200) selects the required fractal.
5.4
The X and Y scales and displacements allow the fractal to be defined
with any size and then re-scaled to fit the screen.
5.4
The ‘probability’ is the probability that that particular equation will
be chosen next. The probabilities must add up to 1. Give transformations
which reduce the size the most the lowest probabilities or they will
fill in too quickly.
5.4
Stick to similitudes at first, because it is easier to work out values
of a, b, c, d, e, f for these.
5.4
Here is some typical data:
5.4
DATA %3
5.4
DATA Fern,4
5.4
DATA 100,500,100,0
5.4
DATA 0,0,0,0.16,0,0,0.01
5.4
DATA 0.85,0.04,-0.04,0.85,0,1.6,0.85
5.4
DATA 0.2,-0.26,0.23,0.22,0,1.6,0.07
5.4
DATA -0.15,0.28,0.26,0.24,0,0.44,0.07
5.4

5.4
DATA %4
5.4
DATA Fractal Tree,4
5.4
DATA 2000,500,2000,0
5.4
DATA 0,0,0,0.5,0,0,0.05
5.4
DATA 0.42,-0.42,0.42,0.42,0,0.2,0.4
5.4
DATA 0.42,0.42,-0.42,0.42,0,0.2,0.4
5.4
DATA 0.1,0,0,0.1,0,0.2,0.15
5.4

5.4
DATA %5
5.4
DATA “Hooks”,3
5.4
DATA 1000,0,1000,0
5.4
DATA 0.5,0,0,0.5,0,0,0.33
5.4
DATA 0.5,0,0,0.5,0.5,0,0.33
5.4
DATA 0,-0.5,0.5,0,1,0.5,0.34
5.4

5.4
DATA %6
5.4
DATA “Boxes”,4
5.4
DATA 1200,0,1000,0
5.4
DATA 0.5,0,0,0.5,0,0.5,0.25
5.4
DATA -0.5,0,0,0.5,1,0.5,0.25
5.4
DATA 0.5,0,0,-0.5,0,0.5,0.25
5.4
DATA 0.33,0,0,0.33,0.33,0.33,0.25
5.4
DATA %7
5.4
DATA “Chaos”,20
5.4
DATA 60,0,60,0
5.4
DATA 0.1,0,0,0.2,1,0  ,0.04:REM C horiz 2
5.4
DATA 0.1,0,0,0.2,1,4  ,0.04:REM C horiz 2
5.4
DATA 0,-0.2,0.25,0,1,0,0.08:REM C vert 5
5.4
DATA 0,-0.2,0.25,0,5,0,0.08:REM H vert 5
5.4
DATA 0,-0.2,0.25,0,7,0,0.08:REM H vert 5
5.4
DATA 0.05,0,0,0.2,5,2 ,0.02:REM H horiz 1
5.4
DATA 0.1,0,0,0.2,8,4  ,0.04:REM A horiz 2
5.4
DATA 0.1,0,0,0.2,8,2  ,0.04:REM A horiz 2
5.4
DATA 0.1,0,0,0.2,9,0  ,0.04:REM A horiz 2
5.4
DATA 0,-0.2,0.1,0,9,0 ,0.04:REM A vert 2
5.4
DATA 0,-0.2,0.2,0,11,1,0.07:REM A vert 4
5.4
DATA 0.2,0,0,0.2,12,0 ,0.07:REM O horiz 4
5.4
DATA 0.2,0,0,0.2,12,4 ,0.07:REM O horiz 4
5.4
DATA 0,-0.2,0.15,0,13,1,0.05:REM O vert 3
5.4
DATA 0,-0.2,0.15,0,16,1,0.05:REM O vert 3
5.4
DATA 0.15,0,0,0.2,17,4,0.05:REM S horiz 3
5.4
DATA 0.15,0,0,0.2,17,2,0.05:REM S horiz 3
5.4
DATA 0.15,0,0,0.2,17,0,0.05:REM S horiz 3
5.4
DATA 0.05,0,0,0.2,17,3,0.02:REM S horiz 1
5.4
DATA 0.05,0,0,0.2,19,1,0.02:REM S horiz 1
5.4
Why are fractals fashionable?
5.4
Mathematicians seem to be fascinated by fractals because they are
beautiful and interesting. However, people who do not find this
sufficient may be impressed that such complicated shapes can be
described with so few numbers. In fact, work is going on now to
investigate the possibility of using fractals to develop more efficient
methods of data compaction.
5.4
References:
5.4
Fractals Everywhere by Michael Barnsley − Academic Press Inc.  A
5.4

5.4
‘Typical fractals are not pretty’ − Barnsley
5.4

5.4
In this example the shape has been rotated by 60° and ‘enlarged’ by a
factor of 0.5.
5.4
So t = 60° and r = 0.5
5.4
Hence
5.4
a = 0.25
5.4
b = − 0.433 (ish)
5.4
c = 0.433 (ish)
5.4
d = 0.25
5.4
Since the shape has been moved 6 across and 2 up:  e = 6 and f = 2
5.4
This result can be checked by calculating the position of a few
transformed points and comparing them with the diagram.
5.4

5.4

5.4

5.4
A Sierpinsky Triangle
5.4
The blobs showing how it can be covered by a collage of  transformations
of itself.
5.4
If the bottom left of the triangle is the point 0,0 then blob R (the
easiest) is given by:
5.4
a = 0.5    b = 0    c = 0    d = 0.5    e = 0    f = 0
5.4
P is given by something like:
5.4
a = 0.5    b = 0    c = 0    d = 0.5    e = 0    f = 0.5
5.4
(e and f depend on the scale chosen)
5.4

5.4
Colton
5.4
From 5.3 page 20
5.4

5.4
Base 5
5.4
From 5.3 page 31
5.4

5.4
PipeLine
5.4
Gerald Fitton
5.4
The current version of PipeDream 4 (December 1991) is version 4.11. This
is not the ‘final’ version because I have a note with mine which says,
“In very early 1992 we will have a version of PipeDream 4 available with
enhanced charts. This will include the following features:
5.4
    Option for log scaling of axes
5.4
    Saving of dynamic charts
5.4
    Option for stacked charts
5.4
    Fill to axis option
5.4
    Line of best fit
5.4
“This will be a free upgrade. If you are interested in these facilities,
please send us your master disc in the new year marked ‘Enhanced charts
upgrade’ so that we can upgrade you when the enhanced version is
available.”
5.4
PipeDream 4 charts
5.4
Anything worthwhile takes a little time. If you have spent some time on
PD4‘s charts and have any hints and tips for others, I shall be most
interested to hear from you. If you have something more substantial on
PD4’s charts then, I assure you, it is in great demand.
5.4
Family trees
5.4
Chris Bell has written to me on this subject. He has the makings of a
database but is running into problems. If you have written such an
application or would like to correspond with Chris about the best way of
storing and recovering such data from PipeDream (3 or 4) then please
write to me and I will forward it to him.
5.4
Sierpinski’s Gasket
5.4
I had not heard of this until Allan Wang asked me what method Sierpinski
used to create his Gasket. If you know anything about Sierpinski or his
Gasket then please write to me! (I suggest you check on the Arcade
Bulletin board. (081−654 −2212) I saw something on there about Sierpin
ski curves. Ed.)
5.4
Z88 Archimedes link
5.4
Don Reekie and many others ask about transferring files between the Z88
and Archimedes. The ‘standard’ way of linking the two machines is to use
an EPROM containing PCLINK in the Z88 and, on the Archimedes, the !Z88
utility provided with PipeDream by Colton Software. Gordon Lindsay-Jones
tells me that the 9-pin to 9-pin cable required to link the Z88 and the
Archimedes is different from the ones usually available for PCs. Hence
problems for the unwary.
5.4
What is the solution? David Holden can supply both a correct cable and
some software for the Archimedes which does not require an EPROM in the
Z88 nor does it require !Z88 running in the Archimedes. Please write to
me if you are interested and I will pass your letters on to David.
5.4
PipeDream printer driver
5.4
John Downard, amongst others (including me), wants an HPjet printer
driver which has been modified to use the PC-8 character set instead of
the ECMA-94 character set used by Colton Software’s version of this
driver. The ECMA-94 set is almost identical to the Archimedes Latin 1
(the default) character set so, if you have ECMA-94 on your printer,
then you need few if any character translations. The PC-8 character set
has a different value for the £ symbol and most other top bit set
characters. If you have modified the HPjet driver to include the PC-8
translations then we would like to hear from you.
5.4
Labels
5.4
Yes! I know that there are many complicated ways of producing labels
with PipeDream which are most useful if you want to write “to all the
members of a hockey club every week” (to quote C A Martin). However,
what he and several others ask for is something much simpler which can
be used on a ‘one off’ basis to print a single label. Perhaps the
simplest system I have seen, up to now, is one devised by John Jordan in
which up to nine lines of column A are used for the address. John sets
his page length, <Ctrl-PY>, to nine lines and then sends the file (one
address if that’s all it is) to his tractor feed printer using a
PipeDream printer driver. His labels are of the 9-lines per label
tractor fed type and so the printer stops in a position ready for the
next label.
5.4
If you have an alternative method, or if you have developed John’s
further, then C A Martin, Derek Banks and many others would like to hear
from you.
5.4
PipeDream Junior?
5.4
No! There is no PipeDream Junior in the pipeline but I have a letter
from Michael Roscoe who considered buying PipeDream 3 and, after trying
out the Demo disc, came to the conclusion that PD3 was not what he
wanted. His specification is for an improved spreadsheet (i.e. better
than PD3) plus built in charts and outline fonts. He was not interested
in the database and word processing functions. His letter implied that
he would like a lower price than that current for PD3.
5.4
Well, PD4 is a much more sophisticated spreadsheet than PD3. I continue
to be pleasantly surprised because, with it, I can now do so many of the
things I thought impossible (or too difficult for me) when I tried them
in PD3. The charts are working well in version 4.11 and promise to get
even better “in very early 1992”. Many of the things I wanted to do with
Presenter but couldn’t, such as pictographs, I can do with PD 4.11.
5.4
However, coming back now to Michael’s requirement, although PD4 meets
his specification for an improved spreadsheet with charts, he will
regret that the database and word processor functions are still present
(and there are some improvements). There are other more broadly based
and more subtle improvements (such as the improved graphic user
interface) and so Michael’s implied requirement for a lower price
(PipeDream Junior was his idea) has not been realised and my opinion is
that that PDJ will not happen. Would you like to see a PipeDream Junior?
What do you think about the price of PipeDream 4?
5.4
Upgrade from PD3 to PD4
5.4
I have begun to see advertisements for PD4 and, by the time you read
this, I am sure that NCS will be offering PD4 to new PipeDream users at
a discount on Colton Software’s price. However, I am advised that, for
the foreseeable future, upgrades from PD3 to PD4 will be available only
direct from Colton Software. Their price for an upgrade is £94.00
including VAT. If you bought PD3 on or after 1 August 1991 then you can
get the upgrade more cheaply.
5.4
Indented paragraphs
5.4
Some of you prefer to use indented paragraphs (as most newspapers and as
I was taught to do at school) rather than the more modern style called
‘blocked’ left. If you do prefer indented paragraphs then, with many
word processors, you just tap the <Tab> key at the beginning of each
paragraph. With most word processors (and DTP applications such as
Impression) this causes no problem if you want to alter the first line
or reformat the whole text. With PipeDream, you can have problems
because <Tab> puts the caret into the next column. If you use <Tab>, the
first line will be in a different column from the remainder of the text.
This gives problems when words are added to the first line and refor
matting sometimes causes columns to slide past each other.
5.4
My advice if you want an indented paragraph is to add a few spaces with
the space bar at the start of each paragraph rather than use <Tab>. It
avoids all the problems.
5.4
Whilst on the subject of word processing, I am surprised how many people
still use <Return> at the end of each line. With any word processor, the
only time you use <Return> is at the end of a paragraph or when you want
to ‘force’ a new line.
5.4
Horizontal spacing
5.4
Many who use outline fonts regularly ask what spacing (characters,
points, etc) <Ctrl-W> and <Ctrl-H> represent. The values are measured in
characters if you are using the system font but, if you print at 100%
using RISC-OS drivers, then what does say an 80 ‘character’ width
produce in inches, centimetres or points on paper? I came up with an
answer for one questioner but she told me later that her printer
couldn’t be working like mine! I now suspect that different printers and
the various RISC-OS printer drivers print out a different width for the
same 80 ‘character’ PipeDream page.
5.4
Here’s an experiment I would like all of you with RISC-OS drivers and
outline fonts to carry out. Create a one line file which has the digits
012345 6789 in an outline font repeated as many times as necessary
across the first line to just fill 50 ‘characters’ (i.e. just fill a
column which has been set so that both <Ctrl-H> and <Ctrl-W> are 50).
You can use a page of fully justified text if you prefer; just set
<Ctrl-H> to 50 and reformat with <Ctrl-R>. Print out the file using your
RISC-OS drivers and then, on the printed paper, measure the width of the
printed line. Having done that, please write to me and let me know the
width or, even better, send me the printed copy. Also let me know the
type of printer and the printer driver you used.
5.4
PipeDream to Impression
5.4
This export utility has been supplied by Colton Software with my PD4. I
don’t know (because I haven’t had a chance to try it yet) whether it
works with PD3 as well as PD4. Give it a try and let me know how you get
on.
5.4
Typing tutor
5.4
John Wakeling has been looking for some time for a typing tutor. Can
anyone help? (How about Turbo Type from Cambridge International
Software? £23 through Archive. Ed.)
5.4
Mathematical modelling
5.4
Gordon Nicholas has sent me a disc containing PipeDream applications for
finding roots of equations, numerical integration, numerical solutions
to differential equations, etc, together with worksheets (for students)
in Impression format. Write to me if you would like to be put in touch
with Gordon.
5.4
Blank sheets
5.4
Derek Banks has PD3, an HP-500 DeskJet and an A3000. With !PrinterLJ he
always gets a blank sheet before printing. Does anyone else have this
problem (I can’t reproduce it)? Can anybody help?
5.4
Invalid number of output bits
5.4
If you get this error message when RISC-OS printing a marked block, you
will be intrested to know that a work around is to move the caret
(cursor) out of the marked block before tapping the <Print> key.
5.4
Address for correspondence
5.4
Write to me at the Abacus Training address on the back inside cover of
Archive.  A
5.4

5.4
PD Column
5.4
David Holden
5.4
Firstly, I would like to correct a misunderstanding arising from my
article in the November Archive. I mentioned various demonstration discs
that are available (‘Crippleware’) and said that these are merely
advertising matter. Unfortunately, in an attempt to be brief I did not
enlarge upon this and I seem to have left many people with the wrong
impression.
5.4
When I said “don’t pay more than the price of a disc” I didn’t mean
about 40p. A more realistic price, bearing in mind postage, packing,
cost of copying etc. would be around two pounds. At this price, most
companies will actually be subsidising the discs and, to return to my
original theme that Crippleware is advertising, this is the way it
should be. If a company is proud of its product and believes it is
better than the opposition, it should be prepared to subsidise these
discs in the same way as it is prepared to pay for other forms of
advertising. If the company is not prepared to subsidise them I would
invite readers to ask themselves why. Are they not quite as confident of
their product as they would have us believe? Would they prefer that we
bought it after reading the conventional adverts or seeing a short
demonstration before we discover its weaknesses as well as its good
points?
5.4
The best means of circulating this type of advertising is, of course, PD
libraries. They have much lower overheads and they can supply discs to a
large market at absolutely no cost to the original supplier. Some cut
down versions of games are already distributed by PD libraries but the
only positive response I obtained during a quick telephone survey
amongst the ‘serious’ software producers was from Colton Software. If
you are running a PD library don’t take that as permission to copy the
Pipedream demo discs. For this you must write to Colton Software and
ask, although I gather that permission will be granted to reputable
libraries.
5.4
The most common excuses given revolve around the Acorn Font Manager and
licences for the various fonts required by most packages. I appreciate
that there are difficulties but I am sure a way around these could be
found if the will existed. After all Computer Concepts recently gave
1500 free copies of an Impression Junior demo to Micro User readers.
5.4
It is often said of advertising that only 10% of it does any good. The
problem is that nobody knows which 10%. I suggest that a functional
program of this type in the hands of someone who is interested in buying
a similar product would almost certainly fall within the ‘useful’ 10%.
It might be thought that ‘free’ discs given with magazines are an
alternative but I don’t agree. The ‘shotgun’ rule of advertising also
applies to these. If the material is distributed by a PD library then
the customer has taken the trouble to send for the disc and has actually
paid for it so must be seriously interested, while the cost to the
originator is absolutely zero. Please software producers, think about
it. What have you got to lose? This must be the cheapest and best form
of advertising available.
5.4
New software
5.4
I have recently been sent two interesting discs by the Archimedes Public
Domain Library at 96 Lanehouse Road, Thornaby, Cleveland TS17 8EA. The
first of these contains a program called AMFtrack which is an editor for
Soundtracker modules. This is similar to the commercial program Tracker.
It seems to do many of the things that Tracker does, but since it’s PD
it’s a lot cheaper! It is certainly worth getting if your interests
extend to this area and you don’t need the extra facilities of Tracker.
5.4
The second disc contains lots of programs and other material about
fractals. This all originates from the Archimedes Fractal Group. Much of
it is not new but it is a good introduction to this fascinating subject.
If you want to know more about fractals, I suggest you get a copy of
this disc which also contains information on the A.F.G.
5.4
Copyright and PD
5.4
There have been major problems recently over copyright amongst some PD
libraries. They are not alone. Some material sent to magazines and
included on their monthly discs has turned out to be copied from other
sources. There is also some confusion over what is copyright and what
isn’t. In fact, there is only one rule that should be observed by
libraries. Everything is copyright. This may not always be true but in
99% of cases it is.
5.4
You might think that if you obtained a program from a PD library then it
should be PD. Unfortunately, since most libraries obtain their material
from other libraries and there is quite a lot of copyright material
circulating this isn’t always the case.
5.4
To understand what Public Domain actually means, we must look at the
source of the term and this, as with much computer jargon, is America.
In the USA there is a law that computer programs originating in national
institutions such as colleges shall be ‘in the public domain’. This is
an eminently sensible law − after all, the material was produced with
public money, so why shouldn’t the public benefit? The problem is that
the term which has a precise legal definition within the U.S.A. has
found its way here where its meaning is much more vague.
5.4
Most of the time, the precise definition doesn’t matter. Many programs
contain documentation which says something like ‘this program is Public
Domain’ or ‘this program may be freely used and distributed’. You might
think that this makes it Public Domain but quite often it doesn’t. PD
programs frequently have conditions attached to this notice. Often this
says that the writer’s name must not be removed and that there must be
no charge made for the program. If the message waiving copyright has any
condition attached, however minor, then the program is NOT public
domain. Once the author has made a program public domain, he/she has no
further rights over it at all, so no conditions can possibly be imposed.
Legally such a statement makes about as much sense as someone making a
will leaving all of his property to himself. If conditions are imposed,
there is a basic contradiction so the material is not public domain.
There is a difference here between a requirement and a request. If an
author says ‘this program is Public Domain but please don’t remove my
name’ it may well be PD but if he says ‘you must not remove my name’
then it certainly isn’t.
5.4
For most purposes there isn’t any difference. If the author has given
permission for his program to be copied, used and distributed without
payment then you are entitled to do all of these things. The main
difference can be seen when commercial organisations become involved.
There is absolutely nothing to stop someone taking a true PD program,
repackaging it, and selling it in the guise of a commercial product.
Acorn actually sold Kermit, albeit with a few additions of their own,
and most purchasers didn’t realise that they were buying PD This is
perfectly legal since the program originated in America and has been
declared Public Domain under USA laws.
5.4
What must be remembered is that unless the program actually is PD you
have absolutely no right to copy or use it. You have only the author’s
permission and if this permission has conditions you are legally obliged
to obey them. If you do not, you are breaking the copyright laws. It is
no defence to say you didn’t see them. In this country, everything is
copyright unless it specifically says otherwise. You won’t find a
message in Archive forbidding you from copying anything published, not
because the material isn’t copyright but because the law says that it is
unless declared otherwise. Similarly with a computer program. You must
assume that it is copyright unless there is a specific message indicat
ing the contrary.
5.4
PD and the A5000
5.4
I have had an interesting letter from Andrew Campbell who points out
that a lot of current PD programs don’t work with the A5000. I realise
that many are made obsolete by RISC-OS 3 since one of the things PD
programs have done is help make up for omissions in the original RISC-OS
and a lot of these have now been corrected. At the moment, we are in
limbo because the new OS exists but only a lucky few who have an A5000
have access to it. I expect that when it is released to us less
fortunate mortals, a new wave of PD programs will appear to make up the
deficiencies in RISC-OS 3. Yes, they will be there, nothing is perfect,
and as usual PD programs will rapidly appear to fill in the gaps. My
worry is that the existing RISC-OS is so good (if you think RISC-OS has
faults try using the highly acclaimed Windows on a P.C.) that if Acorn
price the upgrade too high most users will not upgrade. Incidentally,
don’t be fooled into thinking that earlier models such as the 300 series
won’t be able to use the new version. I am certain that as soon as RISC-
OS 3 is available (probably before) there will be a variety of ‘third
party’ solutions to enable it to be fitted to every model.
5.4
Thanks to sensible pricing combined with the inadequacies of Arthur
almost everyone upgraded to RISC-OS when it appeared. The user base for
the Archimedes has expanded greatly since that time and a lot of that
expansion, thanks to the A3000, has been amongst younger users. The
advantages gained by upgrading to RISC-OS 3 seem much less than from
Arthur to RISC-OS and the price anticipated for the RISC-OS 3 upgrade
seems to be in the region of a hundred pounds, or about three times the
RISC-OS 2 upgrade cost. This is much too high for a lot of people,
especially younger users to whom this will represent an awful lot of
money. If Acorn price it at this level, a large proportion of Archimedes
owners simply won’t upgrade and we will then have two operating systems
in circulation. If you don’t think this is important then read some of
the Atari and Amiga magazines which have lots of letters saying either
‘program X won’t work with my machine which I bought last year’ or ‘why
don’t programs use the extra facilities of my model’. The minor changes
from Basic 1 to Basic 2 on the old BBC micro all those years ago still
create problems and many magazine listings don’t use them. I hope that
most programs will work happily under either OS but if Acorn want to
avoid the confusion that will ensue if we have two versions of RISC-OS
in circulation, I suggest that they greatly reduce the projected price
of RISC-OS 3.  A
5.4

5.4
Watford Electronics’ Mk II ARM3 Upgrade
5.4
Stuart Bell
5.4
If Archive articles had subtitles, then the one for this review would
almost certainly be ‘The Agony and the Ecstasy’. Why? Read on...
5.4
In the world of cars, there are BMWs, (which most of us look at from
afar) which introduce new technological developments before anyone else
but which remain, for financial reasons, never more than the focus of
our dreams. Then there are Fords, which get us from A to B just as well
as the BMWs, but cost rather less.
5.4
The same seems to be true in the world of ARM3 upgrades. People like
Aleph One work at the ‘leading edge’ of technology but their prices,
though recently falling quite dramatically, keep their products out of
the hands of the more impecunious Archimedes owners. The “Ford” of ARM3s
is, perhaps, the Watford Electronics upgrade. The price is lower, but
does it get us from A to B, or from 8 MHz to 25 Mhz, as effectively?
5.4
I started my enquiries when the price for Watford’s Mark 1 upgrade fell
to £299 + VAT. My enquiry about people’s experience of it in the Archive
Help! column brought two responses. One was totally positive, the other
totally negative, on the grounds of the unreliability of the ‘wood and
gold foil’ header which plugged into the old ARM2 socket. Hmmm.
5.4
Then, just before the Acorn User Show in October, I heard about their
“Mark II” upgrade, boasting a newly designed connector and a price of
£199 + VAT!
5.4
Hence, 11.15 a.m. on the Friday of the Show saw me at the Watford stall,
with them already sold out. New supplies arrived by 2 o’clock, so I
returned home expectantly. For the money, you get a four-layer circuit
board, 53mm x 45mm, with a surface-mount ARM3, a 50Mhz crystal, another
chip, and a few capacitors. With the board comes an 8 page A6 leaflet,
with very clear instructions, a disc of utilities and a ‘special
extractor tool’.
5.4
Watford will do the upgrade for £35, including two-way courier service.
I chose the quick DIY method: Stage one: Remove the cover and the floppy
disc drive. No problem. There is no conflict with my IFEL soldered-in
4MB RAM upgrade (which is now available from Archive). Stage two: Use
the special tool to remove the ARM2. Problem! The prongs of the tool
wouldn’t fit the slots in the socket holding the ARM2. So, I gently
filed the prongs until they did fit. Then, apply a gentle rocking
motion, as per the instructions. The prongs − arguably (though I’m
doubtful) weakened by being filed down − bent. Repeat − same result.
Ditto, Ditto.
5.4
A very small flat screw-driver would fit into the ‘south east’ slot, and
apply the leverage that the ‘special extractor tool’ failed to. But, to
get the correct angle at the ‘north west’ corner needed the back-plane
removing, which needed the SCSI podule removing. Once all were out, the
ARM2 device came out quite easily.
5.4
I make no claims to be an engineer, but I have built quite a lot of
hardware for earlier computers. I conclude that the ‘special extraction
tool’ is simply not “man-enough” if the ARM2 is at all reluctant to come
out. My solution was a little time-consuming, but works.
5.4
Stage 3: Rebuild the machine and switch on. All is well. Stage 4:
Activate the !Cache utility and, again, all is well, and much faster!
5.4
The benefits of the ARM3 have been well rehearsed in Archive and don’t
need repetition. One advantage that hasn’t been mentioned much is that
printing can be significantly faster. In my case, the Impression / HP
DeskJet+ combination − certainly not one chosen for speed − took six
minutes for a very complex A4 page with an ARM2. With the upgrade, this
processor-intensive task takes just two minutes. The £199 + VAT is worth
it for this saving alone. Everything runs much more crisply and my four-
year old A310 now runs much like the drooled-over A5000s.
5.4
So what are my conclusions? The ARM3 board itself is superb. It looks
very well made, the new connector seems beyond reproach and the package
undercuts all the other ARM3s by at least £100 + VAT. Similarly, the
documentation and software are fine.
5.4
But, I do not believe that my experience with the ‘special extractor
tool’ will be unique. Even if other ARM2 sockets have wider slots, and
don’t require the tool to be filed down a little, I don’t think that
‘tweezer-type’ tools are adequate to remove four-sided devices like the
ARM2. My approach worked, and I wished that I’d not bothered with the
tool at all. Alternatively, you can pay the extra £35 for Watford to
install it for you.
5.4
In short, after an hour’s “agony”, the “ecstasy” makes it well worth it
at £199 + VAT. I really can’t see the point in paying £299 + VAT or more
for effectively identical products. But it would be even better if the
“special extractor tool” wasn’t so pathetic! With that problem sorted
out, the Watford Electronics Mark II ARM3 upgrade would be like a BMW
for the price of a Lada.  A
5.4
The equation has changed again now as Watford have put their ARM3
upgrade price back up to £249 +VAT, saying it was a Special Show Price
and Aleph One have brought theirs down to £249 +VAT or £280 through
Archive. CJE’s ARM3 (see page 9) has stayed at £199 +VAT (£225 through
Archive). Ed.
5.4

5.4
Lemmings
5.4
Tim Beverley (aged 13)
5.4
Lemmings which was declared “game of the year 1991” has now come to the
Archimedes. It comes in a well decorated box with one disc and an
instruction booklet which contains all the necessary information for
loading, playing the game and what the different icons mean. Also, there
is an example of the game and how to play it, using small illustrations.

5.4
Lemmings are creatures of very little brain, so when they fall out of
their home they just walk onwards regardless, not caring that they are
about to fall to their deaths. The object of the game is to make sure
the lemmings don’t fall to their death by building bridges over the
different kinds of holes and helping them get to their home by digging
horizontally, vertically and diagonally through hills and other
obstacles. You have to do all of this in a given time and you have to
rescue a certain percentage of the lemmings on each of the 120 levels.
5.4
The levels are split up into four categories starting with Fun, which is
to get the player used to controlling the lemmings, then Tricky which is
a little harder, then Taxing which is even harder and lastly Mayhem
which is virtually impossible. There is a different, well-known piece of
music accompanying each level, although this can be switched off if you
prefer.
5.4
At the beginning of each level, it will give you the information you
need to know like how many lemmings there are on that particular level,
what percentage of the lemmings you have to save to complete the level
and the rate at which they will come out of their home. When the
lemmings fall out of their home they come at different speeds, in the
range from 01 to 99 − the higher the number, the faster the lemmings
come out. It is possible to speed up and slow down the rate of the
lemmings by pointing to and clicking on the plus and minus signs in the
bottom left-hand corner of the game screen. The speed at which they come
out is important. At first, you don’t want them to come out too fast as
you may not have chance to set up the necessary bridges, holes etc to
stop them committing suicide, but once the way is clear for them to get
to their new home, speed is of the essence as you have to get enough of
them home before the time runs out. In some levels, the balance between
these two is what is so critical making it difficult to complete
successfully.
5.4
Also at the bottom of the game screen are all the skills that the
lemmings may have. There are Climbers which can climb up vertical
surfaces, Floaters which have parachutes (well, umbrellas!) so that they
can fall down long drops without killing themselves and if a lemming is
given both these skills he is known as an Athlete and these skills last
for the remaining time in that level. Then there are Blockers which stop
other lemmings going past a certain point and Bombers which blow up
single lemmings after a 5 second countdown.
5.4
Other facilities available are, a pause icon which pauses your game and
gives you time to think, a “nuke ‘em” icon which you double click on and
it blows up all the lemmings on that particular level in case you want
to give up and start again and in the bottom right-hand corner there is
a small map of the level that you are on and if you click somewhere on
that map you go to that place on the full screen display.
5.4
There is another menu screen which you automatically go onto after
loading the game. It has four choices, Start which starts the game, New
Level which, once clicked on, makes it possible to type in a password to
jump levels, Music/FX which toggles between playing Lemmings with music
and limited sound effects or no music but full sound effects and an icon
which lets you choose which set of levels you want to play e.g. Fun or
Mayhem and if you choose, for example, Mayhem it starts you off on the
very first level in that set.
5.4
Overall
5.4
The background graphics are very good and the graphics of the actual
lemmings are also quite good given that they are so small. Generally,
the graphics compare very favourably with other games. Lemmings compares
very well with other games in terms of playability and it is very
addictive and can be very frustrating. Indeed, the front cover of the
box has a disclaimer saying that the manufacturers cannot be held
responsible for loss of sleep, hair or sanity of those who play the
game.
5.4
Lemmings costs £24.95 from Krisalis Software or £23 through Archive.  A
5.4

5.4
ScanLight 256
5.4
Tord Eriksson
5.4
The well-known range of ScanLight scanners from Computer Concepts has
lately been extended with two ScanLight 256, one hand held, Junior and
one A4-size flat-bed scanner. There are two different interface cards,
one for Archimedes and one for the A3000. The software and firmware (in
ROM) is the same for all models and the only thing that that differs is
the hardware.
5.4
 Using the ScanLight Junior 256
5.4
It is very easy to get started, at least after you have fitted the card
(mine didn’t fit too well, so I had to do some metalwork). You run the
software from floppy or install it on your hard disc. If you double
click on the scanner file icon, you soon have a bigger scanner icon on
the icon bar.
5.4
When you click on that, you can start using the scanner immediately, by
setting the scanner and control panel to coincide, e.g. the same density
on both. There are switches for scan mode, resolution and brightness
that you can control, in addition to the scan on/off switch.
5.4
You are strongly recommended to use the same scanner driver as the
scanner you are actually using, to be able to use all the functions
available. Most of the time you will get a usable print anyway.
5.4
As the name suggests, it can cope with 256 levels of grey, but your
printer will certainly not! For most uses, 200 d.p.i. with 16 levels of
grey is perfectly all right, but I got better results with the “D”
(dither) option than the 16 level (4 bits-per-pixel) or 256 level (8
bit-per-pixel) option. If this is due to a fault I do not yet know.
Scanning in monochrome was excellent and line-art, like drawings and
printed text, were very well reproduced. (See illustration opposite −
top left.)
5.4
Only Impression II can handle the 176 or 256 levels of grey that the
scanner can produce. Both Paint and Draw makes them into multi-coloured
images that look very scientific but could hardly be called enjoyable!
5.4
The examples opposite are, in my view, really impressive. Both were done
in monochrome, one with hardware dithering (imitating grey by printing
dots), one without. On the whole, line-art was better reproduced than
true grey-scale objects, such as photos, paintings or stamps.
5.4
The software and manuals
5.4
The software adds further complications as it adds sampling to the raw
scan, making it less jagged, quite like anti-aliasing. You can also
control the greyscale etc.
5.4
There is definitely room for some improvement in making the software
easier to use; for instance, the scanned images on screen varies in
size, depending on the resolution you are using, so you spend a lot of
time trying to get them to a practical size. Too small and you can’t see
the details, too big and it flows outside your desktop (memory
permitting!).
5.4
Otherwise, the two manuals gave answers to all the questions you might
have, including a lot of hints and tips about problems that might arise.
One manual is applicable for all versions of hardware and one is
specially for the scanner combination in question. As far as the manuals
are concerned, they are, in short, excellent!
5.4
Conclusion
5.4
If you want to use illustrations in your letters etc. and have got fed
up with the standard clip-art, why not use a scanner and either draw
them yourself or steal them from somewhere!
5.4
It takes much longer to create a drawing on screen, using DrawPlus or
similar, than drawing them on paper and then scanning them in. Or you
can combine the two, using scanned pictures and drawings in your Draw
files, in combination with the usual Bezier curves of Draw or DrawPlus
(Modesty was done with a combination of both!).
5.4
If you use lots of illustrations or need to keep computer files on
people (not allowed in Sweden!), the package is well worth the money.
Disregarding the poor fit of the backplate and the odd quirks of the
software, it is a stable, well-made product that will stand quite a bit
of wear and tear. The Archive price is £245.  A
5.4

5.4
Modesty, by Jim Holdaway,
5.4
and a photo of me and Grandad
5.4
were easily reproduced.
5.4

5.4
Hearsay II
5.4
Mike Hobart
5.4
Hearsay II is a fully RISC-OS compliant, multitasking and much improved
version of the original Hearsay program. Both claim to be the complete
Archimedes communication package, and this would seem to be a fair claim
for Hearsay II. The problem about writing a review of such a comprehen
sive piece of software in this field is that you need a vast array of
hardware to test it on: modems of many sorts, and a link to a mainframe
or mini. I have only used it as a mini-computer terminal, so I restrict
my comments to this aspect. I have had the package for several months,
in two versions, on b-test.
5.4
First impressions
5.4
The program installs itself on the icon bar, with a telephone-and-modem
sprite, and occupies just over 500k, without buffer space. Several
options of terminal are available via menu at this point: Viewdata,
Minitel, ANSI, VT 52, 102, or 350, Tectronics 4105, teletype or Campus
2000, any of which can be set as the default. When you click on the
Hearsay icon, your chosen terminal window appears (in positive or
negative video). Gone is the colourful (garish) front end of Hearsay I!
Within the terminal window, <menu> will bring up a goodly array of
options, most of them with sub-options, even unto the third or fourth
level thereof. There are no ambiguous icons, though you may need to read
a little before settling for your selections. A nice feature is a quick
selection set of radio buttons for the most commonly used line signal
combinations (baud rate, parity and stop bits).
5.4
Mainframe terminals
5.4
The VT terminals are very satisfactory, with a configurable buffer which
allows you to scroll back to stuff which is “offscreen”. Line settings
can be done by hand but there is, again, a very convenient radio-button
quick setup panel. File transfers are easily performed: just drop the
file in the VT window and it will join the output queue. Then ask the
host to receive and select send from the menu. A vast array of file
transfer protocols are available, including X-,Y- and Z- modem and
Kermit.
5.4
The feature which I enjoy best is the Tek terminal. I can make use of
the graphics programs on the lab’s mini supercomputer and zoom in on the
bit I am interested in at the level of the terminal. Best of all, I can
export the graphics as Draw files, for instance straight into Impres
sion, or into a Draw program for further refinement. The result is that
I can have a printout which is better than is available from the big
machine itself. Switching between the text and graphics “planes” is
automatic if your host system supports X-protocols.
5.4
There are other nice touches: I can close the VT window, but leave it
listening out for new data. Or I can close it and reopen, just carrying
on with my session (not good practice, I know, leaving yourself logged
on to a big machine).
5.4
Other features
5.4
Modem users seem to be well catered for, with drivers for a number of
popular models and nice auto-dial facilities. I have not tested any of
these. Nor have I tested one of the more advanced features of Hearsay
II, its C++ - like script language. This allows you to take control of
almost every aspect of the package’s workings and to set it up to do
exactly what you want. I am sure that this is powerful stuff, and since
the author is David Pilling, I am sure it is very well done. However,
since I do not write C, let alone C++, and because I have not felt any
need of the facilities, I cannot comment further.
5.4
Conclusions
5.4
As far as I am concerned, this is the package which we had been waiting
for in the lab. It does everything we want, and it is a pleasure to use.
Our uses are quite limited, however, and this is not a comprehensive
review but if every aspect of the program lives up to what I have used,
I can see few dissatisfied customers. The manual is clear, complete and
comprehensible.
5.4
The program costs £75+VAT from Risc Developments or £82 through
Archive.  A
5.4

5.4
First Words and Pictures
5.4
Simon Anthony
5.4
First Words and Pictures from Chalksoft is an early reading package
aimed at young children and special educational needs students. This is
a very wide range to cover but Chalksoft make a very good stab at it.
The program is written with a careful balance between ease of use and
flexibility which causes a few problems, but they are easy enough to
avoid once they have been recognised.
5.4
The idea of the program is to present a simple everyday scene showing
articles or actions which have to be correctly identified. A word or
sentence describing part of the scene is displayed at the bottom of the
screen and the mouse or cursor keys are used to move a pointer in order
to select the relevant area. An illuminating arrow shows which area is
being selected before the choice is finalised by the reader. If the
answer is right, the selected area enlarges with a gentle tune as a
reward. If it is wrong, the computer ‘sneezes’ as they select it. The
score does not go down and there is no long term indication of failure
to put off the less able reader. After a preset number of questions
there is the option to have another go with the same or different scene.
5.4
The program in action
5.4
The opening screen shows the Chalksoft banner. Pressing <return> gives a
menu with options to allow you to alter every aspect of the program.
There are so many variables that an unassisted user can get lost in its
depths. I would prefer access to this menu to be hidden in much the way
that escaping from the program is achieved, that is by using ctrl +
another key.
5.4
The feel of the main program is pleasant and friendly. The artwork is
primary schoolbook type and the music sounds a little twee. This does
not make for an exciting game but that isn’t the idea. After the preset
number of correct answers has been made, a congratulatory message floats
down the screen while another tune tinkles away happily in the back
ground. There are ten scenes each with eight questions. By changing the
options, these will easily last a morning without repetition. The
options have been designed in consultation with real teachers and are
not just the whim of a back-room programmer. Every time it is used, more
and more subtle aspects emerge due to the flexibility provided. It is
not immediately obvious that the program lifetime would be longer than a
few hours but my experience is that at least special needs students gain
a very great deal and keep coming back for more. The program is not
disturbing to other people in the same room.
5.4
The ‘off computer’ aspects of this package are very important. The
ability to print out the words, sentences and line drawings of the
picture elements and scenes allows colouring in, writing the labels by
hand and simple displays to be made. Learning is improved by using as
many parts of the brain as possible and so these facilities provide good
educational value. They show the care and attention to detail that
typifies the main body of this program.
5.4
One problem that I found is that older children with reading difficul
ties tend to be put off by the childlike presentation. Perhaps Chalksoft
could produce a version of the program with an older emotional feel but
set at the same reading age.
5.4
The program installs easily on a hard disc or network and can be run
from the desktop or autobooted from the disc. It is not copy protected
and so there is no danger of damage to the master disc destroying this
valuable addition to the educational range.
5.4
Conclusion
5.4
First Words and pictures works well. It does teach reading skills and
will hold the attention as long as the user doesn’t feel they are being
patronised by the style. In a group of mixed ability, this can be a
problem. At home or in a matched group of emotionally young pre-readers
there are no such reservations. At £22 plus VAT it is a bit pricey for
the impoverished parent but for an educational establishment it is good
value for money.  A
5.4

5.4
My World
5.4
Doug Weller
5.4
This is a fascinating bit of content free software from Northwest
SEMERC, designed for teachers of special needs children but suitable for
a wide age range in mainstream classes. It was produced  collaboratively
by six LEAs, Cambridgeshire, Derbyshire, Leicestershire, Lincolnshire,
Northamptonshire and Nottinghamshire. Its excellent illustrated manual
was also produced on an Archimedes!
5.4
Object based content free software
5.4
This is an entirely new type of content free software. It was originally
produced to give a teacher of children with very severe learning
difficulties a way of keeping a daily diary without the need to write −
but it has gone far beyond that. Basically, it uses the Draw module in
RISC-OS and screens created by !Draw to provide a wide variety of
contexts in which symbols or pictures (Draw objects) and text can be
easily manipulated, within a fixed structure, using the mouse.
5.4
Using My World
5.4
After loading, My World takes up the whole screen.  A menu is offered
allowing the user to see the various screens that are available, to save
a screen, to print (portrait or landscape, automatically scaled to print
as big as possible) and to change to desktop mode. Desktop mode not only
allows you to use other facilities (for instance, to load a printer
driver if you forgot to do so!) but also offers a magnifier box − this
is particularly useful if it is necessary to adjust the position of
objects precisely.
5.4
Clicking <menu> on the My World icon on the icon bar also gives a choice
of print and display options and also the ability to set the size of the
font cache. This is a real bonus for teachers (probably the majority)
who don’t want to get involved with the RISC-OS Task Manager.
5.4
My Diary
5.4
My World comes with 21 screens, and other screens discs are available.
My Diary is the application the program was originally designed for.
When loaded, the screen shows a diary form (2 blank rectangles with
clock faces under them showing different times of the day) and 14 Rebus
symbols for activities such as swimming, painting, playing, wheelchair,
etc. These objects can be dragged into position simply by pointing at
them, pressing <select> and dragging a copy of the object around the
screen, leaving the original object in place. As this was designed
originally for children with limited fine motor control, there is no
need to hold down <select>. When in place, pressing <select> again drops
the copy at the chosen position. Pressing <adjust> makes it disappear.
5.4
Once this has been done, the object becomes a movable object, which can
be moved around using <select>. If desired, pressing <adjust> returns
the object to its original position. In the left hand corner of the
screen there is a dustbin icon, where objects can be dragged if they are
no longer wanted. A Text icon allows the creation and editing of movable
text objects.
5.4
The screens provided cover a variety of subjects, including Punjabi and
French, sequencing activities using beads, a frog and a car to put
together, sentences to sequence, and a weather map. Any of these screens
can be edited in !Draw and new screens can also be created using !Draw
and the template screen provided.
5.4
Simple Stuff
5.4
There are four ‘Simple Stuff’ additional discs of screens. ‘Simple Stuff
Sampler’ includes a maze, a Pelmanism game, an alien, an electric lamp
and a caterpillar to put together, various maths shapes activities, a
match puzzle screen, etc. A skeleton screen offers you a completed
skeleton made up of 18 objects (bones and groups of bones) which can be
separated and then put back together! This idea is expanded in ‘Simple
Stuff Skeletons’, which is much more detailed and has two versions, one
plain, the other with a ‘ghosted’ drawing to help you. A text pencil
allows labels or notes to be added. A4 scaled !Draw files are also
provided which can be printed out and linked with paper rivets to make
an articulated skeleton.
5.4
The Patterns and Maths discs offer a variety of pattern blocks in the
case of the former, and games and investigations on the latter. Many of
these are very nice but there are a few where I felt that, for most
children, the computer was unnecessary. For instance, real Cuisenaire
rods seem much more interesting than computer ones!
5.4
Summary
5.4
This is a fascinating piece of software with many uses. Some of the
screens provided are excellent; others might be more suitably done away
from the computer, although often computers provide motivation not
otherwise available.
5.4
It costs £15, plus £7.50 for each of the associated discs: Simple Stuff,
Simple Stuff Maths, Simple Stuff Skeletons, Simple Stuff Patterns.  A
5.4

5.4
Notate
5.4
Stewart Watson
5.4
Notate is a new music notation package from Longman Logotron. With their
long history of involvement with education it is no surprise to find
that Notate has been pointed in that same direction. However, like many
other products aimed at education, the potential for private users
should not be overlooked.
5.4
Notate arrives in an attractive A4 box, containing two disks, an A4
manual, a registration card and tear-off keystrip and a reference card.
The two disks are in a sealed envelope, marked “Important − Read before
opening”, followed by the licence terms. The disks are not protected but
a message appears on the screen each time the program is loaded. This
disappears as soon as a key is pressed, but it contains the reference
number of the user. This is, in my view, by far the most sensible form
of software protection offering maximum protection for the manufacturer
together with minimum hassle for the user.
5.4
What can Notate do?
5.4
Here is a list of the claims made in the publicity and some of my
comments on each.
5.4
Up to eight individual staves − Each stave is monophonic (it can only
have one note playing at a time) except for a chord track which I’ll
explain later. Notate was obviously designed with the internal sound
chip as the sound source because a maximum of eight notes at one time is
the limit.
5.4
A wide range of synthesised and sampled sounds − The sounds provided are
varied and excellent.
5.4
Ability to use accidentals and repeats − This works OK.
5.4
Full range of time and key signatures with control over tempo and volume
− Control over tempo and volume is confined to setting the tempo and
overall volume at the start only. That is there is no way at present to
include speeding up and slowing down, or dynamics within a score.
5.4
Automatic checking of note lengths relative to the bar space remaining −
Notate does not allow you to put too many beats in a bar, a ‘Not enough
space in bar’ message appears if you attempt to do this, but it will
allow you to leave a bar incomplete, assuming that the rest of the bar
will be filled with rests.
5.4
Easy-to-use tape recorder control panel − The control panel is very
clearly laid out with all the usual controls.
5.4
Chord facility − This is an interesting feature, as it allows complete
chords to be inserted with one keypress. Once a chord track has been
selected a window opens showing a small note-named keyboard and offering
a choice of major, minor, 6th, 7th, Major 7th, minor 7th, augmented and
diminished. The chord track uses four voices which means that there are
only another four voices available for other parts.
5.4
Mixer control to adjust stereo balance and volume of all tracks − This
is a pop-up window accessed through <f6> which, interestingly, automati
cally reconfigures itself to the number of tracks used.
5.4
Configurability for different levels of user − Like Pendown, Longman’s
word processing package, it is possible to restrict the number of
options available. This makes the screen easier to read, and the program
easier to use, for younger children.
5.4
Editing facilities which, like word processing, include cut, copy, move
and delete within bars staves or between compositions − These editing
functions are well thought out and use the standard Acorn key short
cuts. Selecting a block is down by simply clicking and dragging.
5.4
Up to four compositions editable simultaneously − As Notate allows up to
four songs in memory at one time, sections of one song can easily be
copied into another.
5.4
Ability to transpose single parts or whole compositions − The transpose
options are good in that they allow you to set the key signature as well
as the transposition interval.
5.4
Export and import of MIDI format files allowing transfer between
packages − Files can be imported from Compose World and Inspiration, but
they will have to be monophonic parts. Surprisingly there is no facility
to load Maestro files. Files can be saved in three formats, Notate,
Maestro or Midi. Thus, Notate files can be exported to Genesis and
Magpie, or Rhapsody II into Scoredraw into DTP, if necessary.
5.4
Ability to play via MIDI where a suitable interface is available − It is
because this option is available that it seems strange to have
restricted Notate to eight note polyphony.
5.4
Song files
5.4
The song files supplied are interesting and varied from African drumming
to Rap and from Rock to Classical. The voice modules supplied are
extremely good and the output, when amplified, is very impressive
indeed.
5.4
There is a very good Read_me file inside the application with informa
tion about the Template files and pattern files supplied. These
templates are a very useful way of getting started quickly because they
remove the need for setting up tracks and voices. The pattern files
contain basic rhythm patterns which can be used as building blocks.
5.4
Printouts
5.4
The options for printout are large, medium and small, portrait or
landscape. The quality is good though pixelated (a new word but I like
it. Ed.), comparable with a printout from Rhapsody II but not as good as
Scorewriter or ScoreDraw.
5.4
Summary
5.4
Notate is a well structured package and what it does, it does well. The
writers have done their homework and produced a product that I think
will be well received by the education market.
5.4
It seems a pity that the conditions of use prohibit the copying of any
part of the documentation, as there are fifteen pages of ideas for
teachers to try with pupils and there are accompanying song files
supplied on the program disk. These pages could easily have been
supplied as a set of worksheets with no copying restrictions thus saving
a lot of retyping. Another possibility would have been to supply the
text on disc ready to be customised and printed.
5.4
There are one or two worrying limitations. There is no provision for
real time input, though it is promised in the first upgrade in early
1992. There is only scope for two lines of text, a title and composer,
no choice of size or format and no lyrics. This is an area that the
writers are currently exploring and developments in this area are
probably afoot.
5.4
The version I am reviewing is 1.00 and is a well thought out, well
presented package. A lot of time and effort has gone in to saving users
time and trouble. If you need a package to enable you, or your pupils,
to get music onto paper, or want to experiment with composition, Notate
could well be the package you have been waiting for.
5.4
Notate is available from Longman Logotron price £59 + VAT for a single
user (or £64 inc VAT through Archive) or £190 + VAT for a primary school
site licence or £330 + VAT for a secondary school site licence.  A
5.4

5.4
Astronomy on your Desktop
5.4
David Taylor
5.4
I have produced a standard wimp application based on some of the
astronomy routines in Shareware 10. The application, named !Daylight,
displays the times of sunrise, sunset, moonrise, moonset and the
beginning and end of civil twilight for any date and for anywhere on
earth at the click of a mouse. The program could be very useful for
historians, for authors of historical novels or for anyone planning
future activities dependent upon daylight. The ease of use of the
graphical interface and the astonishing speed of recalculation demon
strate the capability of the Archimedes perfectly.
5.4
!Daylight uses two new filetypes, location which holds latitude,
longitude and placename and filetype event which holds a particular date
in addition to the other data. Double clicking on one of these file
icons will start the application with that file already loaded,
calculated and displayed in two seconds or less. Alternatively, you can
start the application by double clicking on the !Daylight icon and a
location file named “default” held in the application directory will be
loaded and calculated for today’s date. The default file can easily be
altered by the user to hold his or her home town or location of choice.
These filetypes are not registered with Acorn so conflict is possible.
Once the application is running, fresh locations or events may be loaded
either by double clicking on their icons or by dragging the icons to the
main window, all precisely according to the Acorn guidelines.
5.4
The latitude and longitude are displayed in writable icons and may be
changed at will. The time displayed initially is zone time which does
not take account of summer time or other national idiosyncrasies. The
zone time is shown in a writable icon and the event times displayed are
modified whenever this icon is changed. By setting this icon to
longitude divided by 15, local mean time is displayed. Click on the word
zone and it will change to local. The time then shown is the local
apparent time based on the sun being on the local meridian at 12h00.
This is the most appropriate time to use in a historical context since
mean time has only come into common use in the last hundred years with
the general availability of accurate clocks. Zone time has only appeared
since the introduction of radio time signals. The time displayed can be
changed to Universal Time by clicking on the word local. In all cases
the events displayed are for the date at the location of interest.
5.4
If you play with the arrows under the date for a few minutes you will
discover that the date may be changed by the day, month, year or
century. The date displayed changes from the Julian to the Gregorian
calendar in 1582. Thursday, October 4th, was followed by Friday October
15th. This is a function of the library procedures and since it was by
Papal decree, I have not had the temerity to change it, although the
Gregorian calendar was not adopted in protestant Britain until 1752. In
consequence, dates given between 1582 and 1752 in British history books
may have to be converted from the Julian or old style calendar to the
Gregorian or new style calendar. Add ten days between 5th October 1582
and 29th February 1700. Add eleven days between 1st March 1700 and
September 1752. The retrospective dates on the Julian Calendar are not
taken back before Saturday, 1st January in Anno Domini 1. There seems to
be no firm agreement on whether a year 0 should be included or not. It
is all hypothetical in either case. Any historian seeking accuracy to a
particular day before this date would be well advised to work directly
to the scale of Julian days.
5.4
The menu leads to save boxes for event files, location files or text
files. If a text file is dragged to !Edit or !Impression, the file is
transferred without being written to disc first. I have seen frequent
mention of this multitasking facility but have yet to see another
application written in Basic that does this.
5.4
I undertook this project as an exercise in programming the graphic
interface. The hands-on experience has been invaluable. I did not expect
to have to rewrite astronomy routines. The original routines of Dr
P.J.Duffet-Smith are excellent. For any time given as a Julian day and
fraction thereof, they evaluate the ecliptic longitude from a polynomial
and then transform it to Right Ascension and Declination, allowing for
parallax. These routines found their way to the Archimedes through D.
Fangandini and Ivor Clarke who converted them to BBC Basic style
procedures but still left all the GOTOs in place. The GOTOs are now
replaced by structured control statements so the procedures may be used
as a separate library and the logic is easier to follow.
5.4
The sunrise problem is one of those calculations where the numbers
required to give a solution depend upon the solution. This is more
evident in the case of the moon than of the sun. Moonrise, which can
occur at any time of day, is a function of Right Ascension which changes
at a mean rate of 51 minutes per day. To calculate the Right Ascension,
you need to know the time of moonrise and you cannot calculate the time
of moonrise without the Right Ascension. The computer is suited to using
the iterative method in solving these problems. The more iterations
used, the longer the solution takes. Even the Archimedes takes a moment
to work through the many polynomials describing the moon’s complex
motions.
5.4
In rewriting the procedure that calculates moonrise and moonset, I have
reduced the number of times that the Right Ascension of the moon is
evaluated from seven to four without degrading the accuracy of the final
result. There were other reasons for rewriting the rising and setting
procedures. The old routines kept on stepping into the wrong day
particularly when calculating events away from the meridian of
Greenwich.
5.4
The time of sunset is calculated for the instant when the centre of the
sun is at an altitude of 0 degrees relative to the horizontal plane of
the observer. The sun is then described as having a zenith distance (the
angle from the observer’s vertical) of 90 degrees. Owing to the dip of
the observer’s horizon below the horizontal, and the effect of atmos
pheric refraction, neither of which is a constant, it is generally
accepted that the moment of sunset is that when the lower limb of the
sun touches the visible horizon. It is therefore not practical to
display sunset times to the nearest second although the original
routines did this.
5.4
A new procedure added to the library calculates the times of the
beginning and end of civil twilight. These are the limiting moments when
the horizon is clearly visible at sea or a grey goose can be seen at a
mile on land. The corresponding zenith distance is 96 degrees.
5.4
The diagram shows how the hour angle and azimuth at sunrise and sunset
are derived from right ascension and declination. It shows the relevant
triangles on the surface of the celestial sphere viewed from outside.
The celestial sphere is a mythical ball of indeterminate radius onto
which the bodies are projected from the point of view of the observer.
The actual radius is not required because all the distances which are
the lengths of the sides of the triangles used are arcs of great circles
and measured as angles at the centre of the sphere. Events are seen by
the observer, O at the centre of the sphere. PP‘ is the polar axis and
ASBR is the observer’s horizontal plane. RSNM represents the path of the
sun through the sky, rising at R and setting at S. The sides of the
spherical triangles required are RZ or SZ, the observer’s zenith
distance, which is always 90 degrees, PR or PS, the sun’s co-declination
and PZ, which is the observer’s co-latitude. ZPR and ZPS are the hour
angles and PZR and PZS the azimuths for rising and setting respectively.
5.4
From the usual spherical triangle formula
5.4

5.4
since the zenith distance is 90 and cos90 = 0, this may be simplified
to:
5.4

5.4
There has been quite a lot of interest recently in calendars and dates
and I am sure that this application will be of interest to some of the
Archive readers. If you are interested to take this project further,
please contact me at 64, Redmond Road, Hamilton Hill, 6163, Western
Australia.  A
5.4

5.4
Break 147 & SuperPool
5.4
Patrick Bean
5.4
This is the latest offering (well, one of them! Ed) from the Fourth
Dimension, who brought us E-type, Powerband, Holed out and Chocks away,
so expectations are high. The games come on three disks, one master disk
and one for each of the two games. I wonder if this means that we can
expect to see more table games running under this same system?
5.4
On running either game, you are presented with a menu offering demo,
practice, match and tournament. In Demo, the computer simply plays
against itself. Practice lets the user place balls anywhere on the table
and play from that position, so trick shots and the like can be set up.
Match lets two players, one of which can be the computer, play a match
of up to 35 frames. Tournament lets you set up a competition with many
players. On selecting match, a second menu appears. From this menu it is
possible to save and re-load matches, set the number of frames in the
match and set the volume level. A table of results can also be dis
played. This second menu can be returned to by pressing <escape> during
the game.
5.4
After the two menus, you are shown a 3D view of the table. Moving the
mouse left turns the table right and vice versa. At first, this can make
you feel a little sea sick as the table and balls roll around before
your eyes. It will not take long, however, to get the hang of the
control system. You can position yourself (your viewpoint) anywhere.
Even height can be changed so making bridge shots easier. When your
viewpoint is correct, just click on <select> and your cue will appear in
front of you on the table and in the top left-hand corner of the sceen
along with a large cue ball with a dot on it. This dot shows the point
at which the cue will strike the ball, so that fine adjustments can be
made in order to give spin etc.
5.4
When you are happy, draw back your cue (mouse) and push it forward, the
speed at which you do this determines the power of the shot. That is all
there is to it − no power guages as in some other simulations. On
striking the ball, some very good sampled sound adds to the overall
realism. If, after the shot, there is a touching ball, the referee will
announce the fact and the ball in question will flash.
5.4
In the event of you missing the ball or committing some foul, the
referee will inform you of your transgression, again in high quality
sampled speech. All rules of both games appear to have been implemented
correctly. On potting the cue ball, it is placed in the “D” from where
you can position it exactly. Once you have taken your shot, you can
again move your viewpoint even while the balls are still moving! If you
heard a ball go down but did not see where it went you have the ability
to replay the shot viewed from any angle. Alternatively, you can set an
option in one of the menus so that a particular ball involved in the
shot can be tracked to its final resting point. A dotted line can also
be displayed before you take the shot showing the path along which the
cue ball will travel.
5.4
Practice mode should be used at first in order to familiarise yourself
with the control system. After that you can use the match option to play
either against the computer or another human. Later, a tournament can be
setup with a number of players of both types. The computer’s play is of
a very high class, as can be seen from the demo mode. It’s potting and
positional play are good but it is not quite so careful about where
other balls such as the BLACK! are going. Its skill is almost unbelie
vable with double and cut type shots.
5.4
The documentation states that..... “The ball calculation accuracy in
both of these simulations is to a scale movement of plus or minus 0.635
of a millimetre. In addition to this, the rotational accuracy is to 1.75
minutes of arc. Or to put it another way, in ‘Break 147’ you can hit a
ball in any of 12,288 directions from any one of 4,147,200 possible
locations on the table.” However, in order to utilise this, a monitor
with a display of 2880 by 1440 pixels would have to be manufactured.
Such a display mode would need 4 Megabytes of screen ram!
5.4
Overall
5.4
This game looks like being another winner for the Fourth Dimension. My
only complaints are that the table is a little fast (the balls can
sometimes float around the table as if they were in outer space) and the
computers play is far too good!!!
5.4
Well done Fourth Dimension and Mr. Keys. Break 147 & SuperPool costs
£24.95.  A
5.4

5.4
Scientific Software − Computer Algebra
5.4
Brian Cowan
5.4
There has been some correspondence in another magazine concerning
scientific software − or the lack of it − for the Archimedes. Although I
generally concern myself with matters of hardware in the columns of
Archive, in my day-time job as a scientist I use all manner of scienti
fic software. I thought it would be a good idea to acquaint interested
readers with what is available. So I am proposing to write an occasional
column which, over the next few months, will discuss and review all
manner of Archimedes software which has a scientific connection.
5.4
Currently I have had experience of using specialised products in the
following areas: Computer algebra − mainly Reduce but also Derive under
the PC emulator, General scientific DTP − Impression and TEX, Equation
generation for DTP − Equasor and the newly released BestForm, Statisti
cal software − First from Serious Statistical Software, Graph and data
plotting − Chris Johnson’s GraphDraw and other programs. Some of my
students and I have developed software in other areas, which might be
covered in some future articles. If there are any more categories of
scientific software which readers are interested in, please let me know
and I will try and cover them.
5.4
Archimedes only
5.4
My main concern will be for dedicated Archimedes software although, for
comparison, I will occasionally mention DOS software which can run under
the PC emulator. My general impression is that there is a growing
collection of scientific software available which, while not able to
compete with DOS or Mac software in sheer quantity, certainly makes up
for this by quality and power − helped of course by the raw power of the
ARM. Writing for DOS machines is a real challenge − it is the modern day
equivalent of trying to make a silk purse out of a sow’s ear − but ARM
programmers should not become blasé and complacent. Computer Concepts
have shown the way in terms of what can be achieved; other software
houses know the standards to which they should aspire.
5.4
Computer algebra
5.4
There is a danger in trying to re-invent the wheel. A few years ago
(well, quite a few actually!) I did not even know of the existence of
computer algebra software. I had a really interesting problem involving
the manipulation of some algebraic equations which I was doing using the
quaint methods of pencil and paper. It soon dawned on me that I should
not spend time doing things I was not good at: I am much too careless at
that sort of thing. I realised that my computer, an original BBC model
B, would make fewer mistakes. Thus I sat down and wrote a program in BBC
Basic to perform my algebraic calculations. It worked well, even if it
took all night to do some of the more complicated operations. I even
invested in a 32016 second processor, such was my enthusiasm, and then I
graduated to an Archimedes. From then on, I was hooked on computer
algebra and, in reading all about it, I discovered that there was a
range of commercial software packages available.
5.4
More than just algebra
5.4
It is worth pointing out that the term computer algebra is rather an
understatement for this sort of software. As a minimum, most packages
include the following facilities: arithmetic to arbitrary precision,
manipulation of algebraic quantities such as multiplying and dividing
algebraic expressions, operations with matrices including the solution
of linear equations, solution of other classes of equations, different
iation and integration of algebraic expressions.
5.4
Available packages
5.4
There is a range of computer algebra packages around for a variety of
different computers. The list of packages includes Scratchpad, Mathe
matica, Macsyma, Maple, Reduce and Derive. Each have their own
advantages and disadvantages and, generally, a particular package has
its particular computer type or types on which it runs. To the best of
my knowledge, Reduce is the only system which runs on the Archimedes in
native mode; Derive, which runs under DOS, is usable with the PC
emulator. Many algebra packages are written in Lisp, which is ideally
suited for such applications.
5.4
Reduce
5.4
Reduce is one of the older of the computer algebra packages around. It
was originally developed specifically for doing calculations in quantum
electrodynamics, but it soon blossomed into a general system with many
applications. These days, it is much-beloved of those concerned with
computer algebra research and it boasts probably the best indefinite
integration facilities around.
5.4
Calculus
5.4
I should perhaps explain a few things about “computer calculus”. Of
course, differentiation and integration are the inverse of each other
but, as every maths student knows, differentiation is relatively
straightforward while integration is not. One seems to have to learn
many methods for integration and to have to guess which method to use
when. The fact is that there is always a definite procedure to be
followed when differentiating an expression; differentiation is
algorithmic. Conversely, integration is not. It is thus difficult to
program a computer to perform integration. A great breakthrough came
with the discovery of the Risch-Norman algorithm which, for the first
time, provided a well-defined procedure to be followed in integrating a
wide class of functions − this is the same Norman, guru of Acorn, who is
associated with various of the language compilers for the Archimedes,
including C and Lisp.
5.4
Other facilities
5.4
Reduce performs all the tasks mentioned in the check list above and it
performs them well and quickly. One of the advantages of it being an
established package is that there is an increasing number of third party
(public domain) programs available which can be incorporated for all
sorts of purposes. Thus, the latest Archimedes version comes with the
following PD add-ons: Vector algebra and calculus, Calculus of modern
differential geometry, Generation of code in various computer languages,
Groebner bases, Limits, Solution of ordinary differential equations, 3-D
vector analysis in curvilinear coordinates, Root finding, Symmetries of
partial differential equations, Summation of series, Taylor and other
power series.
5.4
The next few sections will show some examples of what can be done. The
first listing is the summary of a Reduce session.
5.4
Example 1 − Magnetic field calculation
5.4
The problem here is to produce a uniform magnetic field at the centre
between two similar circular coils. The field is most uniform when the
coil separation bears a certain relation to their diameter. This is
known as the Helmholtz configuration. The Reduce session finds the
required coil separation and then it calculates the field homogeneity at
the centre.
5.4
Each line of input in a session is numbered. I have deleted some lines
in the interests of clarity and space. So here we start with line 2 in
which I typed in the formula for the magnetic field at the centre
between two coils. The radius of the coils is taken as unity, Z is the
distance along the axis from the centre and LH is the separation of the
coils. I terminated the first line with a $ which causes the program not
to echo the result of the input.
5.4
Line 3 substitutes the value 0 for Z in the formula for the field; this
gives the magnetic field at the centre. As this line is terminated by a
; the result is printed out on the next few lines. Note that the outputs
are printed in lower case, while the inputs are in upper case.
5.4
In line 4 we want to find the derivative of the field at the centre. A
double operation has been done here. DF(BH,Z) differentiates BH with
respect to Z and then the value Z=0 is substituted in. The answer is on
the next line. It is zero. There is no magnetic field gradient at the
centre and in fact by symmetry all odd derivatives vanish there.
5.4
The second derivative is evaluated in line 5. See how the function DF
can be used for higher derivatives. As in line 4, the value Z=0 has been
substituted in as we are interested in what is happening at the centre.
I did not want to print out the cumbersome result, so the line is
terminated with a $ and, in line 6, I told it I wanted things to be
factorized.
5.4
The symbol WS stands for work space, meaning the contents of a particu
lar “line”. Line 7 tells the program to evaluate line 5, and it is
printed out in factorized form.
5.4
The Helmholtz configuration is that which makes this second derivative
zero. We want to find the separation LH which results in this. This is
done in line 9 which solves the equation LS=0 for LH. The equation has
four roots, as shown in the curly brackets. The imaginary roots are
clearly non-physical and the two real roots are physically equivalent:
LH=½, telling us that the separation of the coils should be half their
diameter.
5.4
In line 10, we explicitly set LH to be ½, so that it is no longer a
variable. Note that global assignment is effected with the Algol/Pascal
:= symbol while the usual equals sign = is used for arithmetic equality
and local assignment.
5.4
The resultant field at the centre is then obtained from line 12 and, as
we can see, the answer is exact; no rounding is done. It is up to the
user to specify the precision for floating point approximations.
5.4
At this stage, I decided to load in a third party program to express the
magnetic field in a power series in Z. The TPS package is much more
efficient and fast than successive differentiation followed by substitu
tion. The package is loaded in line 13 and it is used in line 14. PS is
one of the functions provided, giving a power series. We want the field
BH expanded in powers of Z about the point Z=0. The result follows. The
first term, independent of X is the field at the centre, as calculated
above. The next term is in Z4, indicating that all lower order deriva
tives vanish.
5.4
Obviously, such a calculation could be done by hand but, apart from the
effort involved, there is always the possibility of making silly errors.
5.4
Example 2 − Power series
5.4
Before I had the TPS package, I had written my own power series
procedures. These are shown in the second listing. Lines starting with a
% are comments. The procedures are given the self-explanatory names
TAYLOR and MACLAURIN, and their definitions are fairly straightforward.
The statement SCALAR is the equivalent of LOCAL in Basic while the
structure of the FOR loop is very similar to that in Basic.
5.4
Example 3 − Definite integration
5.4
One serious limitation of Reduce is that it does not do definite
integration, although the indefinite integration (anti-derivative)
facilities are second to none. The third listing shows a short procedure
for evaluating the definite integral by substituting at the end points.
Of course, this is the usual method of doing this and, for respectable
functions, it works well. For badly behaved functions it will not work
and of course, as it stands, this function will not cope with infinite
limits.
5.4
Archimedes Reduce implementation
5.4
I have been using Reduce version 3.3 on the Archimedes for some few
years. This was a single-task program which took over the whole machine,
although I had hacked the program about to make it run in a Task Window.
This obviously slowed the program down somewhat but the advantages were
plenty. I could then edit procedures and chunks of instructions in an
Edit window, and I could see where files were, in their directory
viewers. Then by unlinking the Task window I could export chunks of a
session as text to a document. In fact, this is how the first listing
was produced. This version of Reduce ran under the Acorn Lisp compiler
(now discontinued).
5.4
It should be pointed out that Reduce is hungry for RAM. It requires a
minimum of 2 Mbytes to run and it is better with more. All algebra
packages, by their very nature, need large amounts of RAM. It is
remarkable that the PC Derive works as well as it does within the DOS
constraint of 640k; much work must have gone into optimising the code to
run well in a small area of RAM.
5.4
Reduce version 3.4 is now available and I have had my copy for a few
weeks now. This uses CSL Lisp: Codemist Standard Lisp, which is a new
version for the Archimedes, written mainly in C. This has the advantage
of having hooks to the window manager etc. Not surprisingly, version 3.4
runs in its own window and installs itself on the icon bar. However,
there are a number of differences from standard RISC-OS applications.
While a Reduce calculation is being done, control is not passed back to
the machine. This is quite a good idea and it means that there is no
significant speed loss by running in a window. You can scroll back over
the window a limited way but unfortunately there are no cut/paste
facilities. In that respect, it is not so good as my hacked version 3.3.
In principle, however, I should be able to get the new version running
in a Task window; I have not tried yet.
5.4
Another advantage of the old version was that there was a graphics
module, written by Arthur Norman, which (in single-task mode only)
provided some elementary 2d and 3d graph plotting. This obviously does
not work with the new version so, at the moment, there is no graphics
support. Within a windowing environment, the sensible thing to do is to
export the graphics data to a graphics window. Thus all Reduce must do
is to prepare the data for export. It then becomes the task of the
graphics widow to do the display properly. I have been working on this
but I still have a long way to go!
5.4
The Archimedes package
5.4
Reduce 3.4 comes on eight floppy discs! In fact, the compiled program is
on two disc, the others containing the sources, libraries and documenta
tion. Unfortunately you don’t get the full CSL Lisp package; this must
be purchased extra if you need it for development work. There are two
manuals provided. One is the documentation for Reduce 3.4 and the other
contains information on the user-contributed modules. These manuals are
perfect-bound and I am worried that they will fall apart soon if they
are used too much. Fortunately, the documentation on the discs includes
these manuals but they are in TEX format and so can not be read directly
without a TEX previewer.
5.4
Conclusion
5.4
I estimate that Reduce is my second most used software package (Impres
sion + Equasor being my first). I have found it invaluable despite its
few shortcomings. It is probably rather too expensive for the casual
user but for serious mathematical work it is superb. It is much more
powerful than Derive, although that package does definite integration
and it provides graphics facilities. Unfortunately, I have not had an
opportunity to use Mathematica, which is supposed to be good and has
excellent graphics, but there is no Archimedes version available; nor is
there likely to be.
5.4
The full price of Reduce 3.4 is £320 + VAT but, until the end of the
year, owners of Reduce 3.3 can upgrade for £185 + VAT.
5.4
Archimedes Reduce 3.4 is available from:
5.4
Codemist Ltd., “Alta”, Horsecombe Vale, Combe Down, Bath, BA2 5QR.
Telephone: 0225− 837430.
5.4
Example 1
5.4

5.4
2: BH := 1/((Z—LH)**2 +1)**(3/2) + 1/((Z+LH)**2 +1)**(3/2)$
5.4
3: SUB(Z=0,BH);
5.4

5.4
                2
5.4
           2*(lh  + 1)
5.4
—————————————————————————————————
5.4
        2         4       2
5.4
 sqrt(lh  + 1)*(lh  + 2*lh  + 1)
5.4

5.4
4: SUB(Z=0,DF(BH,Z));
5.4

5.4
0
5.4

5.4
5: SUB(Z=0,DF(BH,Z,2))$
5.4
6: ON FACTOR;
5.4

5.4
7: WS 5;
5.4

5.4
 6*(2*lh + 1)*(2*lh — 1)
5.4
——————————————————————————
5.4
        2         2     3
5.4
 sqrt(lh  + 1)*(lh  + 1)
5.4

5.4
9: SOLVE(WS(5)=0,LH);
5.4

5.4
        1      1
5.4
{——— ,lh=———,lh= — i,lh=i}
5.4
        2      2
5.4

5.4
10: LH := 1/2$
5.4

5.4

5.4
12: SUB(Z=0,BH);
5.4

5.4
    16
5.4
———————————
5.4
 5*sqrt(5)
5.4

5.4
13: IN “$.!REDUCE.R34.RED.TPS”$
5.4

5.4

5.4
14: PS(BH,Z,0);
5.4

5.4

5.4
  16*sqrt(5)          2304        4        315392        6      7
5.4
(————————————) — (—————————————)*z  + (———————————————)*z  + O(z )
5.4
      25           625*sqrt(5)          78125*sqrt(5)
5.4

5.4
Example 2
5.4

5.4
% TAY/MAC
5.4
%                TAYLOR AND MACLAURIN EXPANSIONS      BPC/7July89
5.4

5.4
% For the Taylor expansion
5.4
%     1st argument is the function
5.4
%     2nd argument is the expansion variable
5.4
%     3rd argument is the point of expansion
5.4
%     4th argument is maximum power required
5.4

5.4
% For the Maclaurin expansion
5.4
%     1st argument is the function
5.4
%     2nd argument is the expansion variable
5.4
%     3rd argument is maximum power required
5.4

5.4
   PROCEDURE TAYLOR(F,X,X0,N);
5.4
      BEGIN
5.4
         SCALAR SS, DD, FA;
5.4
         DD := F;
5.4
         SS := SUB(X=X0,F);
5.4
         FA := 1;
5.4
         FOR I := 1:N DO
5.4
            BEGIN
5.4
               FA := FA*I;
5.4
               DD := DF(DD,X);
5.4
               SS := SS + SUB(X=X0,DD)*X**I/FA;
5.4
            END;
5.4
         RETURN SS;
5.4
      END;
5.4

5.4

5.4
   PROCEDURE MACLAURIN(F,X,N);
5.4
      BEGIN
5.4
         SCALAR SS, DD, FA;
5.4
         DD := F;           % the function - for repeated
differentiation
5.4
         SS := SUB(X=0,F);  % partial sum of terms
5.4
         FA := 1;           % for the factorials
5.4
         FOR I := 1:N DO
5.4
            BEGIN
5.4
               FA := FA*I;
5.4
               DD := DF(DD,X);
5.4
               SS := SS + SUB(X=0,DD)*X**I/FA;
5.4
            END;
5.4
         RETURN SS;
5.4
      END;
5.4

5.4
   END;  A
5.4

5.4
Example 3
5.4

5.4
algebraic procedure defint(y,x,a,b);
5.4
      begin
5.4
         scalar integ;
5.4
         integ := int(y,x);
5.4
         return
5.4
         sub(x=b,integ) - sub(x=a,integ)
5.4
      end;
5.4
end$
5.4

5.4

5.4
Sinewaver
5.4
Tristan Cooper
5.4
If you have ever been fascinated by the shapes formed by sine waves,
especially when more than one of them interfere with each other, then
this selection of programs from ‘Jimbo’ of Computer World is for you.
Jimbo is clearly entranced by the behaviour of sine waves and makes
extensive use of them in various graphical ways, using text, blobs, dots
and lines. He allows us to create a wide variety of fascinating shapes
using the Archimedes’ speed and colours to great effect.
5.4
Before I describe Sinewaver itself, here is a quick rundown of all the
other programs on the disc.
5.4
•    Tunes − five sound tracks to give you some background music.
5.4
•    !Mellow − an interesting selection of exercises in coloured graphics,
giving smooth colour control, but with inadequate explanation (see
below).
5.4
•    !Paletter − a comprehensive and easy to use means of producing your
own palette.
5.4
•    Key2Dots − a less than exciting display of moving blobs or lines.
5.4
•    MouseyFun − plot lines or dots on the screen and they’ll be slowly
deleted after a while. Fun?
5.4
•    PlainDotty − this gives you a feel for the shape of things to come as
sine wave related movement is depicted using moving coloured blobs. But
don’t believe the instructions − you’ll need / & ‘ not . & ; to alter
the values.
5.4
•    Vectors-3D − rotating tetrahedron in basic colours.
5.4
•    Autorotate − I couldn’t make this do anything useful due to lack of
detailed instructions.
5.4
•    Keyrotate − select one of several line drawings and rotate it through
all possible axes.
5.4
•    Shapemaker − make your own drawing for use with Keyrotate.
5.4
•    BasicFX − some attractive exercises in text manipulation which could
be nice to use in one’s own applications.
5.4
•    BirdMaths − a pretty representation of a bird flaps around the screen.
5.4
•    Dycp − type in your own text and see it bounce up and down.
5.4
•    SineDemo − demo version of Sinewaver.
5.4
•    Waveydesk − yet another ‘facility’ to make a mess of the desktop.
5.4
•    Wiggle − a broad coloured line streams down the screen under mouse
control.
5.4
!Sinewaver
5.4
Getting Sinewaver to start is not the easiest thing in the world! I
think Jimbo is a little over protective of his software, frankly.
Firstly, is there really a need for a window to open asking whether I’m
legally entitled to use this software? particularly as there is no way
to close it. Secondly, the password codes are written on crimson paper
with crimson highlighting. The intention is to make it impossible to
photocopy it; unfortunately, it also makes it very hard to read. Then,
the instructions for use of the passcodes is so ambiguous that I had to
contact Jimbo to find out how to use them! Call me stupid if you like,
but I bet I won’t be the only one to fail to get past this stage without
help.
5.4
Once running, Sinewaver gives us a main menu with options on playing
with the sinewaves, editing, saving and loading data, merging sinewaves,
information and quit.
5.4
At this point, the best bet is to go for ‘playing’ and see what happens.
This is the default setting in which 30 spots swirl around the screen in
an elliptical form. Try holding <shift> and/or <ctrl>. These cause non
deletion of the spots and cycling of colours, producing some very pretty
effects. Pity they can’t be saved as sprite files. Clicking <select>
will send you to the editor, allowing alteration of all the parameters
currently in use, in terms of x and y radii, counts, speeds and steps,
Sine counts and phases; plus number of dots, after images and phases.
I’m not at all sure quite what all these mean, and there is no explana
tion that I can find to tell me. However, altering some of them,
particularly the last three, then returning to the display, produces
patterns of increasing intricacy and delight. At this point, you might
feel that your perseverance is starting to pay off. By experimenting
with different values of the various parameters, you will eventually get
a feel for what everything does and should be able to maintain a
sensible display and produce a vast variety of pretty shapes at the same
time. Take your time and don’t change more than one thing at a time
until you fully understand what’s going on.
5.4
There are a number of default sine waves that have been supplied which
can be combined in various mathematical ways such as addition, subtrac
tion, division etc, and some default parameter settings which are worth
trying out.
5.4
The information page is not very informative, unfortunately. Jimbo uses
some of his text manipulation tricks to produce a rather garish and
uncomfortable display which includes little useful data. Which takes me
to my main grouse...
5.4
Criticism
5.4
I have no doubt that Jimbo knows a great deal about sinewaves and
programming the Archimedes. However, as with so many programmers, he
seems to assume that the users of his work will be able to read his mind
when it comes to actually running the programs. What is the use of
sophisticated software, capable of producing fascinating and entrancing
effects, if we can’t understand how to use it? There can be no doubt
that many hours of blood, sweat and tears went into writing this wide
range of programs. A couple of hours of careful thought, perhaps with
the help of an inexperienced user, might lead to two or three pages of
clear instructions, plus comprehensive on-screen help.
5.4
Conclusion
5.4
I understand that the asking price for this software is around £4. It’s
easily worth that much, notwithstanding the criticisms, and Jimbo tells
me that he intends to do something about the instructions. Let’s hope
so. There is also a competition for the most original and interesting
Sinewaver pattern. So for more details, contact Jimbo, (aka James
Wilkinson) 13, St Peter’s Road, Droitwich, WR9 7BJ.  A
5.4

5.4
AnDi Oddule
5.4
Peter Thomson
5.4
The AnDi Oddule is the first of a series of modules from Baildon
Electronics and Morley Electronics Ltd that communicate with the
Archimedes computers through the I2C interface.
5.4
AnDi is an an input / output unit with both analogue and digital
interfaces. It costs £49 +VAT.
5.4
I2C interface
5.4
The I2C bus is an integral part of the Archimedes computer’s internal
communication system. It is a standard system for exchange of data
between integrated circuits and forms part of the expansion bus. The
Oddule’s lead plugs into an adaptor that in turn plugs into the
expansion socket. At only £84+VAT this is the lowest cost option. The
Oddules can also plug into the I2C socket on Morley’s Analogue and User
Port for A3000 expansion board. The Oddules can be daisy-chained so that
several can be used on one interface at the same time.
5.4
Analogue input
5.4
This unit is quite fast. It can collect up to 10,000 analogue values per
second in total from four channels. These are 8 bit conversions and all
8 bits are available with no internal noise degrading readings.
5.4
The voltage to be measured must be between 0V and 5V. If an external
reference voltage, less than 5V, is used then the conversion is between
0V and the reference voltage. The converter can also be configured to
measure the difference between two channels. The input circuit draws
less than 0.1 nA except when the voltage moves outside the permitted
range. Any channel not in use should be tied to analogue ground and not
left floating.
5.4
Analogue output
5.4
There is one channel available which can be outputting a signal at the
same time as the analogue input or digital input / output is in use.
Potentially, this is also very fast at 10,000 changes per second but
providing meaningful data at this speed requires assembly language
programming skills. This interface will cope easily with the fastest
programming available in Basic. This output is also an 8 bit conversion
between 0V and 5V or between 0V and a reference voltage. This output
cannot drive a large current and an amplifier using an external power
source is needed to make full use of it.
5.4
Digital input / output
5.4
There are 8 digital channels giving eight input and eight output
connections. Each channel can be configured separately as input or
output. The input uses 5V logic, and when this is connected, will also
drive the output for that channel.
5.4
The digital output should be connected to an external DC power supply up
to 50V with a maximum current of 400mA on one channel and a total
maximum of 1A for all eight channels.
5.4
Hardware
5.4
The unit is mounted in an 8cm by 14cm plastic case with all connections
to the top surface. All connections are made to the analogue and digital
terminals with screw clamp bare wire connectors. There is a single LED
that shows the 5V line to the Archimedes is on.
5.4
A 5V terminal is provided on the module. If this is short-circuited, it
is protected by a diode, but may result in failure of the diode in a
fail safe mode. The diode then needs replacing.
5.4
The electronics inside is based on four chips, each mounted in a socket
and easily replaced should the need arise. The digital output device can
be directly substituted with a higher voltage rated chip.
5.4
Software
5.4
All functions of this module are under the control of a single command;
SWI “IIC_Control” (&240)
5.4
Several modules might be in use on the I2C bus at the same time. The
first parameter is the address that identifies the module to be
controlled. The address can be changed by altering links inside the
module. The least significant bit of the address includes a 1 to read
data from the module, or a zero to send data to the module.
5.4
The second parameter is the pointer to a block of data. If the operation
is to send data to the module then this data will be placed here before
the SWI is used. If it is reading data from the module then the data
will be placed here by the SWI.
5.4
The third parameter is the number of bytes of data to be sent or to be
collected. This is only limited by the memory available for the reserved
block of data.
5.4
The SWI in ROM on the Archimedes cannot support the highest rates of
data transfer to the module. An improved version is available from
Baildon Electronics. This worked well with all options except four
channel analogue conversion at the highest possible speed, when it does
not start with the same channel each time it is used but Baildon
Electronics have now ironed out this minor problem.
5.4
User Guide
5.4
The user guide gives detailed technical information and is very
comprehensive in this respect, including circuit diagrams for the
modules and examples of circuits for connection. This may be too
technical for some users as it assumes a general knowledge of digital
electronics, but is essential for project development. Perhaps a
separate guide to experiments without the technical background would be
useful.
5.4
The user guide explains SWI “IIC_Control” and gives a listing that
demonstrates the features of the module. This listing includes functions
for most input and output routines that could be included in other
programs. It would be useful for the novice programmer if this listing
was explained in more detail.
5.4
Conclusion
5.4
The AnDi Odule is excellent value for money. The connections are not
suitable for young children but for GCSE work and ‘A’ level project work
it seems ideal. The possibility of increasing the number of channels
available by daisy chaining units must make it a practical solution for
teaching interfacing at university level and for industrial development.
5.4
Software control of the unit is straight forward − I would expect it to
be adopted by most control software packages in the future. It is
already supported by “Sparkle” control software.  A
5.4

5.4
Saving Disk Space
5.4
Mike Hobart
5.4
This article started as a review of Compression, but Stuart Bell’s got
published with great speed. Had I been as quick writing mine, the gist
would have been much the same. The advertisements tell you that you can
“double your disc space”, and this is not an unreasonable claim, though
it does need some qualification. As usual, it is a case of “you can’t
get something for nothing”. I have a suspicious turn of mind, so I did a
bit of extra research before sending off the review and got some
surprises.
5.4
Strategies
5.4
The following seem to be possible strategies for making sure that you
have the storage you want:
5.4
1. Invest in hardware. The options range from higher density floppies,
through bigger or removable hard drives to tape-streamers and optical
storage. They all cost money.
5.4
2. Compress the data. I have experience of two systems: Compression and
Spark. Both have their uses, as explained below.
5.4
3. Get more organised. This is the solution favoured by Gerald Fitton,
who uses PipeDream for all the jobs which do not need the DTP features
of Impression, partly because it is much more economical in storage
space (Archive 5.2 p36). It is a very sensible strategy, but most of us
are weak-willed, as the inside front cover often points out!
5.4
Compression programs
5.4
Compression programs do contain a special danger: every bit (hopefully!)
of a compressed file becomes significant. This is bad news for Adrian
Look, who wrote the no-doubt excellent Archimedes Disc Rescue. The
problem is that compressed files are total gobbledegook (well, to
paraphrase a bit from the old Apple II manual, if you can read them,
then you are a mutant and will go far in computing!), so a little gentle
mucking about with the odd bit on the disc will totally destroy the
data, whereas in plain form it just wrecks a character or a Basic token.
5.4
Compression (CFS) appears to serve essentially the same main purpose as
Spark. However, there are important differences, which makes possession
of both attractive (see table). CFS is immensely faster and demands less
space and workspace. However, it does not offer encryption, nor does it
know about other compression formats and it costs much more. The
compression each achieves is very similar, not surprising as they both
apply the same algorithm.
5.4
At least, this is how it might seem if you ask for a count on your
directories and files, but it is not that simple. Most important, CFS
does not compress directories, which means that they and their contents
can swiftly be accessed. Spark does archive the directories, and so it
can save a great deal more space. As far as I can see, it does not
compress them, or at least not all of them, but it does cut out the free
space.
5.4
There is a funny “feature” of count: it does not take directories into
consideration. The result of all this is that, although the effective
ness of the two programs is about the same on files, and by count they
seem to be doing the same, Spark can make a dramatically better job of
compressing directory trees. The drawback is that you need enough free
space and time to unpack your way to where you want to go, and you
cannot run applications direct from an archive. They have to be unpacked
first. Spark is a far better archiving program than Compression, but it
does cost time.
5.4
Sadly, Compression is at a disadvantage where I would like it most: the
compression of short items generated in Impression. As all Impression
users know, every Impression document is saved as an application, in
other words, a directory tree including !run and !runimage files. Each
chapter has a subdirectory and there is a master chapter directory. It
is therefore possible to produce a vast amount of storage demand by
saying next to nothing in a number of chapters or a number of documents.
On the other hand, if you write a book as a single “chapter”, the
overheads are relatively trivial. Compression will do well with the book
but appallingly with the multi-chapter document. However, you might
never know this, unless you measure the change in your free space.
5.4
Problems with CFS
5.4
The problems are all avoidable, but take note, all the following is
based on genuine experience, which may not improve my image as an
intelligent computer user!
5.4
1. If your hard disc is brim full, then buying any data compression
program will be very frustrating. You can compress your data, but you
will have to make some space first by off-loading onto another medium.
The amount of space you can free determines how conveniently you can do
the compression of existing files. Each file which you compress must be
compressed into a different directory from that in which it currently
lives. You can compress whole directories at a stroke, but you need
enough free space to copy the source directory in its compressed form.
It is only after the file or directory has been compressed that you can
claim your new space by deleting the uncompressed parent. The smaller
the amount of free space you have available, the more piecemeal your
approach must be.
5.4
2. Some file types do not respond to compression, as their data is too
unstructured, or (in other words) because they are already efficiently
organised in terms of space occupancy. Programs and fonts are the most
obvious examples. Compression will not compress files which it considers
not to be worthwhile.
5.4
3. It is possible to compress files which you would much rather not
compress. If you do accidentally compress your boot file, you can sort
things out by restarting the machine with shift depressed. Then you can
open file windows, start CFS manually, drag the compressed file from the
CFS directory to a “direct” directory (not the root directory), check it
is O.K. and then delete the compressed boot file and replace it with the
uncompressed one.
5.4
4. There is a fatal clash between CFS and the Z88 filer program that
comes with Pipedream. Following the dreaded “Abort on data transfer at
....”, all filing systems (other than PCDir) are irretrievably lost, as
far as I can tell. I have tried to *RMreinit, without effect. BIG RED
BUTTON TIME!
5.4
Discipline for Impression users
5.4
If you need to save space as an Impression user, the best answer is to
save text only, not whole documents, and then compress the text. It is a
bit of a bore, but it gives dramatic savings for short documents. Also,
do not save graphics both as source and copy in Impression. If you want
to save them in Impression, you can dump the source and get at them by
holding down <shift> while double clicking on the Impression directory
icon, thus opening its filer window for further rummaging.
5.4
Discipline for other material
5.4
It may also be worth hunting out rubbish in bought-in and PD programs.
Do you need all the documentation within the application? Do not pass on
PD programs without it, but possibly remove it from your working copies.
Does the application include modules which you already have in your
system folder? It is not uncommon to find copies of CLib, ABClib and
FPE. Do you need all the examples and “freebies”?
5.4
Examine all your files: have you used it this quarter? If not, archive
it. Have you used it this year? If not, dump it on a labelled floppy in
a cardboard box! Have you looked in the cardboard box this millennium?
Well, perhaps I am getting ahead of myself, and we shall all have
infinite optical drives by 2000 AD.
5.4
Make sure that you leave some space on your hard disk, preferably at
least 10%.
5.4
Conclusion
5.4
Buy a storage system which is plenty big enough for your imagined needs,
preferably one with the option of adding. I am a fan of removable
drives, indeed, I suspect that I was the first to use one on an
Archimedes. A removable can get you out of all sorts of difficulties.
5.4
Buy Compression unless you are a speed freak, you can afford infinite
storage or you are paranoid. To my surprise, someone who should be “in
the know” suggested to me the other day that there is no speed penalty
in using CFS to unpack files, as the computing time is more than
compensated for by the reduced file transfer time. Probably depends on
your hardware − more true for ARM3 and less true with express SCSI
drives.
5.4
Buy Spark for your deep archives.
5.4
Use neither for core bits of your system (!boot, fonts and programs).
5.4
Tidy up your disks at no financial penalty. Use the space saving options
offered by Impression or compact storage offered by (e.g.) Pipedream.
5.4
a) Large directory of assorted stuff, but few sprites, many sub-
directories.
5.4
Before compression     3,554,304
5.4
CFS’d by count    1,266,304     35.6%
5.4
CFS’d by D free     2,479,104     69.7%
5.4
Sparked by D free    1,246,208     35.1%
5.4
Time to CFS    2.5 mins
5.4
Time to Spark    25 mins
5.4
b) Large single chapter in Impression.
5.4
Before compression    143,772
5.4
CFS’d by count     73,632    51.2%
5.4
CFS’d by D free     77,056    53.6%
5.4
Sparked by D free     64,768    45.0%
  A
5.4

5.4
Clares’ Illusionist
5.4
Malcolm Banthorpe
5.4
Illusionist is a graphics package designed for editing and rendering 3D
objects and scenes allowing very realistic images to be generated.
5.4
I have written previously about ray-tracers such as RenderBender,
SolidsRender and ArcLight which attempt to generate realistic images by
effectively taking into account the paths of all rays of light from a
scene which reach the viewer by both direct and indirect routes and is
thus able to take into account reflections and transparency. The main
drawback to this approach is the time taken to render a scene.
5.4
Illusionist goes for a simpler approach of rendering whole polygons at a
time, taking into account direct lighting and thereby allowing pictures
to be generated in a fraction of the time that would be taken for ray-
tracing. The penalty for this speed is that the shadows cast by objects
cannot be shown (although surface shading can) and neither can mirrored
or transparent objects be represented. If this were all that there was
to Illusionist, it would be a fairly useful 3D editor and rendering
system but not a particularly remarkable piece of software.
5.4
There are, however, a number of facilities which make it something
rather special. Notably, sprite and picture files can be mapped onto the
surface of any object so that they can be given the texture of, say,
wood or marble. Secondly, although all surfaces are defined as polygons,
smooth shading may be applied. This results in a much better representa
tion of surfaces which are supposed to look smooth. While the actual
shape of an object is not changed by this operation, by defining a
surface as a large enough number of polygons and applying smooth
shading, the effect is the same as if the surface were perfectly smooth.
For example, depending on its screen size, a cylinder composed of 20
polygons will generally appear to have a circular cross-section. When
these features are coupled with anti-aliasing and a very effective
colour-dithering algorithm, the result is some of the most realistic
images I have yet seen generated on an Archimedes. The extra reality
given to objects by texture-mapping and smooth-shading more than
compensates, in many instances, for the lack of shadows and other
limitations.
5.4
The editor
5.4
Illusionist is supplied as two discs and a 56 page manual. The main disc
contains the !Illusion application, plus a number of components for
picture building and some example pictures while the second disc
contains more components and examples. Once the main application has
been installed on the icon bar, clicking on it brings up an edit window
which is used to design objects and scenes. The window consists of four
panes showing top, side and front views plus preview. The latter shows
the scene in wire-frame format taking into account the observer
position, target and lens. This view can optionally be displayed full
screen. To the left of the edit window is a toolbox providing access to
the most commonly used ways of creating and manipulating objects. Other
facilities are available via menus and also, in many cases, via keyboard
short-cuts. The top, side and front views can be zoomed and panned to
facilitate detailed work on them but I would have preferred them to be
in the form of resizeable windows so that they could also be enlarged.
5.4
Objects are always defined in terms of series of polygonal facets, each
of which is defined as a series of connected points. An object may
therefore be created from scratch, polygon by polygon, entering a series
of points by clicking as the cursor is positioned appropriately in all
three windows, and then entering how the points are connected. The
cursor may be positioned by the mouse purely visually or, optionally,
the three coordinates of the cursor may be displayed so that pre-planned
objects can be accurately defined and positioned. This is, however, the
most time consuming way of defining objects and need only generally be
employed for irregular shapes. Many objects can be adequately repre
sented using a selection of the built-in primitive shapes such as
sphere, cube, hemisphere, torus, cone, etc. As any shape can be
independently scaled in each of three planes, there is plenty of scope
for creating new objects. In addition, “sweep” objects can be defined by
rotating a profile. This makes it easy to create circular shapes
typified by goblets, vases and cups. A single polygon may also be
extruded into three dimensions. An optionally displayed variable grid
and grid lock are available. An unusual but potentially useful feature
is called “attract”. Here the cursor looks like, and behaves like, a
magnet. Any selected group of points are drawn towards the magnet, the
degree of attraction for any given point being proportional to its
distance from the magnet. This, together with scaling, provides plenty
of scope for distorting the primitives into new solids.
5.4
Once an object has been defined, it may be necessary to access a single
facet in order to adjust its position or to define its colour or texture
map. To do this, it will be necessary to select all of the points which
define that surface. This operation is fundamental to the operation of
Illusionist but is, as the manual admits, a little complex to explain in
words. However, after following the example in the manual, it turns out
to be a lot easier to do than it first appears and, fortunately, the
process does not have to be repeated all that often. Any selected group
of points (from a single point through a group of facets to a collection
of objects) can be given a label which will then appear in a separate
label window. Thereafter, that group of points may be reselected merely
by clicking on the label. I learned early on in my exploration of
Illusionist that it is a very good idea to give a label to everything,
as soon as it has been defined − this can save a lot of time later. As
mentioned above, any group can be scaled in any direction as well as
rotated and positioned so that complete scenes can easily be built up.
Complete scenes may be saved to disc as a “vector” file which will also
contain information concerning surface colours and textures. By saving
single objects, they may then be used in future by merging them into new
scenes.
5.4
Surfaces
5.4
Any surfaces can be assigned a colour or texture map and given a surface
type such as matt, metal, shiny, plastic or self-luminous. Colours are
not limited, as in the case of RenderBender, to 14 but are defined as 24
bit values with 256 levels each of red, blue and green, giving a
theoretical total of 16,777,216. A texture map is a mode 12 or 13
sprite. As well as the sample maps provided, new ones could be created
with any suitable paint package such as !Paint or Artisan. A scanner or
digitiser and camera could also be useful here. Facets may be rendered
as the flat surfaces that they really are or with smooth shading. The
precise way in which the sprite is mapped onto a surface may also be
defined − for example, you can select the number of times that the
sprite is repeated over a surface.
5.4
The surface type determines how specular reflections (highlights) are
handled. Ideally, metal surfaces should often include a reflection of
surrounding objects. While reflections are not strictly speaking
possible with this package, there is a feature called environment
mapping which, used with care, can contribute greatly to the realism. An
‘environment’ is the optionally rendered background to a scene defined
in terms of four colours. By default these are: sky top − blue, sky
horizon − white, ground horizon − black, ground bottom − green. For any
surface, the degree to which the environment is reflected can be defined
and helps particularly in making metallic surfaces look realistic.
5.4
Lighting
5.4
Up to fourteen lamps may be positioned to light a scene and there are
two types of lamps available. Point lights shine all directions while
spot lamps are directional and have variable beam width. The colours of
both types can be defined in terms of red, green and blue components.
The overall brightness of a scene and ambient lighting can also be set.
Some care with the positioning of lamps will help to make the missing
shadows less obvious. One effect of their absence can be to make an
object on a horizontal surface appear to be floating above it.
5.4
Rendering
5.4
When it comes to actually rendering a scene, it is a good idea to start
with a “mini test”. This is just approximately 1/16th of a screen and
gives some idea of any changes to lighting or positions of objects or
viewpoint that may be desirable. Full screen rendering can be in any
256-colour mode and may either be multitasking or take over the
processor, with the screen optionally disabled, for maximum speed. If
the anti-aliasing option is chosen, four values are calculated for each
screen pixel (therefore taking four times as long) but the resulting
image is superior in having jagged edges smoothed out. If you are lucky
enough to have a PCATS Graphics Enhancer, this is also catered for.
Images may be finally saved either in compressed form or as standard
sprites. It is possible so save the complete 24-bit information,
although a single mode 21 image would take up 960 k. The wire-frame view
may be saved in !Draw format.
5.4
Conclusions
5.4
Overall, I was very impressed with this package. Apart from my minor
niggle with the small size of the design windows, I found it easy to
use. It is the first application of its kind that I have seen for the
Archimedes and is capable of results that look as though they were
produced on something very much more expensive. Highly recommended.
(£99.95 from Clares Micros or £89 through Archive.)  A
5.4

5.4
Prime Art & Imagine
5.4
Peter Thomson
5.4
Both PrimeArt and Imagine are art packages which use the mode 15 screen
display as the painting area. They both use the RISC-OS printer drivers
and the outline font manager but they are very different in most other
respects.
5.4
Icons and menus
5.4
Clicking <menu> on Prime Art’s screen displays an icon based toolbox
menu. This includes a colour selector at the top and a very useful text
help panel at the bottom. An array of 32 icons provides immediate access
to a wide range of painting and drawing options. I thought the icons
were rather too small to start with but once I had identified the
function of each, I found no difficulty in using them.
5.4
I also appreciated the rapid access to many of the options. Pressing
<menu> a second time on the toolbox or selecting the relevant icon
displays a text menu with a comprehensive range of options.
5.4
Imagine only provides a series of text menus with a fairly complex tree
structure. The selection of a new option requires this system to be
negotiated each time which I found annoying. Imagine also has a help
facility which displays text windows at each stage of the menu selec
tion. These were useful the first time I ran the program but after that
I found them very intrusive and switched that option off.
5.4
My testing panel of seven and eight year olds had little or no dif
ficulty making selections from Prime Art’s menus but found those of
Imagine very frustrating.
5.4
Configured menus
5.4
Both packages provide a facility to limit the selection of options
available to young children. Imagine does this by simply deleting the
option from the menu tree. Prime Art offers a much more sophisticated
facility to place the chosen options on the toolbox. All 32 icon spaces
on the toolbox can be assigned in any order to any of the options
available in the package. The same icon may be present several times to
produce a larger button area.
5.4
Colour choice
5.4
Prime Art has a simple colour display system that takes up very little
space on the toolbox. Two columns each display the eight basic palette
colours. One from each column is selected. A horizontal band between the
two now shows all the shade variations in between. Although the squares
of colour are tiny, my testing panel found it simple to use, and easier
than the colour sliders in !Draw.
5.4
Imagine uses a palette that displays all 256 colours as a square on the
screen. Again the individual colours are tiny. Choosing a colour is made
more difficult because the colours in the palette don’t quite match the
same colour when placed on the screen,
5.4
Brushes and sprays
5.4
Imagine has the bigger selection of brushes. It has two basic brush
shapes in each of four sizes. You can also pick up a line of pixels from
the screen which then becomes a brush or paint with a small rectangle of
pixels to produce a texture effect. Sprays can be round or square and
the user can define the size and density.
5.4
Prime Art has six brush shapes selected from the tool kit that function
for both spray and painting.
5.4
Colour fill
5.4
Prime Art can produce some spectacular effects with a range of banded
colour fills in addition to plain fill. The colours used are the shade
variations between any two of the eight basic palette combinations
giving fifty-six colour patterns. The colour change is either smooth or
banded, fitted round other colours or not, round or vertical or
horizontal.
5.4
Unlike ProArtisan, the width of each band cannot be changed.
5.4
Imagine can only offer a plain fill with an option to fill to a colour
in addition to replacing an area of one colour.
5.4
Shapes
5.4
Both packages offer straight lines as well as outline and filled shapes
in triangle, rectangle, circle, ellipse sector, segment and arc. Imagine
also offers square, parallelogram and spiral. The last is not easy to
control.
5.4
Cut, paste and sprites
5.4
Imagine uses the screen as the work area for these options which has a
serious defect; you cannot place a copy that overlaps the original
without risk that the new copy covers part of the original before it has
been copied. Rectangular areas of the screen can be flipped left-right
or up-down. The option Transform allows a copy to be rotated, enlarged
or reduced as well as fitted into any four sided area.
5.4
Prime Art uses the much more flexible system of sprites. Any rectangle
can be copied from the screen as a sprite and added to a RISC-OS sprite
file. Sprites can be imported from other packages or exported to them.
Any sprite can be selected and scaled to any size, rotated to any angle
before placing on the screen. The selected sprite can be used to tile
any rectangular area, or a tiled pattern of sprites used in a flood fill
or painting option.
5.4
Printing
5.4
Both use RISC-OS printer drivers. Prime Art allows the whole screen to
be printed in various sizes, including a four page poster size. With
Imagine, the printer driver must be loaded before the program but any
part of the screen can be selected and printed out.
5.4
Prime Art special options
5.4
The Prime Art application sits on the icon bar. Other applications
remain intact but not accessible while the drawing screen is in use, but
you can switch between the desktop and the drawing screen which also
remains intact. This means that you can run Paint alongside as a sprite
editor. The review version would only allow exchange of the sprite file
via disc, but the next version should allow Prime Art and Paint to work
on the same sprite file. I found it useful to run two copies of Prime
Art side by side in the same machine. They do not interfere with each
other at all and sprites can be exchanged via disc. I used a RAM disc in
a 2Mb A3000 and found this very easy.
5.4
This package has two painting options called Mix and Cover which allow
the shade of a new colour to be modified by the colour previously on the
screen. This is particularly useful for adding light and shade to a
scene and also for adding colour to a digitised photo. Wash blends the
shades between groups of pixels, and a ‘cycle brush’ cycles through the
shades of a chosen pair of colours. I was pleased to see the return of
Rays, straight lines radiating from a point which was a feature of the
art package that came out with the first 310s and Arthur.
5.4
All options in the next version will be selectable with a single key on
the keyboard in addition to the toolbox and the text menus. The review
version has the keyboard short-cuts but you need to follow the menu
structure. This will be a very useful feature when it is implemented.
5.4
Imagine special options
5.4
Imagine has two alternative screens but one is lost if the other is
printed. Although other applications remain intact, there is no way of
interacting with them. Other pictures can only be loaded as full mode 15
screens. Sprites cannot be loaded or saved. A novel feature is that the
whole of the screen can be covered by a pattern of lines formed from
triangles, squares, hexagons, circles or any quadrilateral. The size of
the shape and the way the lines are displayed can be selected. Another
feature is that an area of the screen can be selected and copied in a
brick like pattern to cover the whole screen. The horizontal offset can
be adjusted.
5.4
One feature I particularly liked was the use of symmetries in drawing.
The line that you draw is repeated with a symmetry centred on the middle
of the screen. Those available are left/right, up/down and up to eight
fold rotational symmetry.
5.4
Documentation
5.4
Both guides describe all the options available. The guide for Prime Art
is better presented and includes illustrations of the toolbox and all
the menus. I also prefer its wire comb binding which allows it to remain
flat on the desk.
5.4
Conclusion
5.4
Both programs have some interesting features but Prime Art stands out as
being easy to use with all its features easily accessible for even the
youngest user. It doesn’t have all the features of ‘ProArtisan’, but has
some which that package lacks including the ability to interact with
other packages on the desktop. Prime Art is certainly my best buy.
5.4
Prime Art from Minerva Software costs £79.95 + VAT (or £87 through
Archive) and includes a primary school site licence.
5.4
Imagine from Topologika is £39.95 (£37 through Archive) and includes a
school site licence.  A
5.4

5.4
Step By Step Video Guides
5.4
Peter Jennings
5.4
Learning how to use a computer or a new piece of software is made so
much easier if you are fortunate enough to have someone to show you what
to do. Most of us have had to rely on reading instruction manuals, and
perhaps magazine articles, followed by trial and lots of error. Now, for
the first time, there is a series of four video guides to demonstrate
how to make a start in computing, text processing, data handling and art
and graphics, all using the A3000/Archimedes range. They cost £14.95
each (£14 from Archive) and running times vary from 55 to 80 minutes.
The full price is a half or a quarter that charged for some videos
designed for PC machines, where the potential sales are much bigger.
5.4
The videos come in smartly labelled plastic cases, illustrated with an
A3000 and small screen shots and with a lengthy blurb on the back,
detailing the contents. Above the title of each is the legend: “A step
by step guide to the Acorn BBC A3000 and Archimedes range +
applications”. This is the only mention anywhere that the videos are
designed for users of anything other than the A3000. The details on the
back and the commentary on tape refer only to “your A3000” with no
acknowledgment that you may be using any other model. This does not
really matter except, perhaps, to a complete beginner getting to grips
with the machine for the first time who may wonder if he has bought the
wrong model, or the wrong video, if his micro is not an A3000.
5.4
Professional videos are expensive to produce and, with a market limited
to A3000 and Archimedes users, they have, of necessity, to be low
budget. These appear to be made with a single camera with production
techniques limited to a few changes of shot, some screen insets and an
occasional mix. The presentation is adequate rather than polished. More
important, though, are the videos’ contents and the way the instruction
is given and both of these are generally good.
5.4
Up & Running
5.4
The first and, at 80 minutes, the longest in the series, is “Up &
Running” which is aimed at the complete beginner. I found the start
confusing and my first thought was that the wrong tape had been put in
the box. The opening titles ended with some down-screen wording saying
“Other titles in this series” then a full screen title: “No. 2 Text
Processing” and a commentary which began by talking about word process
ing and desk top publishing. I had to rerun it and read the introduction
more carefully to realise that this was an advertisement for the other
three videos, taking up about the first three minutes of the tape.
5.4
The instructions began with presenter Graham Pragnell opening the box of
an A3000 Learning Curve and displaying the contents. The manuals were
put aside, never to be seen or referred to again. The viewer was then
shown how to connect the computer to various types of monitor and to a
printer. Everything was clearly explained and Graham Pragnell quickly
established his credentials as an actual user by advising that the mouse
plug was a tight fit and giving his own tip for inserting it. There was
no mention that other Archimedes have a separate keyboard and slightly
different connections and do not need a monitor support. A brief look at
a 400 series machine would have been a good idea here.
5.4
With the A3000 all connected and switched on, the normal start-up screen
was shown then a demonstration of what to do if there was just a * on an
otherwise blank screen (switch off and switch on again while holding
down the “R” key). The mouse was demonstrated, with insets of the screen
to show the pointer movements, and the terms “software”, “hardware” and
“WIMP” were explained. No previous knowledge was assumed. Even the
correct way round to insert a disc was shown and everything was taken at
a slow, steady pace with close ups and screen shots to make the
instruction clear.
5.4
That took up about the first 15 minutes of the tape and most of the rest
was devoted to tutorials on using some of the programs on the two
applications discs, beginning with Configure and going on to Edit, Paint
and Draw. Programs were saved on a previously prepared disc, titled
“Housekeep” but confusingly referred to, at different times, as “working
disc” and “storage” as well as “housekeeping”. The programs were named
as “Graham1”, “Graham2”, “Graham3” and so on, with no suggestion of
giving meaningful titles. Default file names such as “Untitled” were
cleared, a character at a time with the Delete key rather than the time-
saving <ctrl-U>.
5.4
The instruction was given as one long tutorial although it is unlikely
that anyone just learning to use a computer would be able to assimilate
it all at one sitting. I think it would have been better to separate
different sections with some visual punctuation, such as a picture flip,
with perhaps a music “sting”. This would also have made it easier to
find the different subjects when spooling through on subsequent
viewings. The first section, on assembling the computer, would be
unlikely to be viewed again once the machine had been set up. A mix
between subjects was occasionally used on other tapes in the series.
5.4
Text Processing
5.4
The second tape, Text Processing, is said on the case to be 70 minutes
long but the cassette label shows a more accurate “75 mins approx”. It
demonstrated the use of two word processors, First Word Plus and Phases,
which is for younger users and was described as being half way toward
desk top publishing, and one full blown desktop publisher, Ovation. I
was particularly interested in the tutorial on Phases as this was a
program I knew nothing about. The instructions showed how to produce an
illustrated document, printed in two columns, with different fonts and
text in varying sizes and colours. Even with no prior knowledge of the
program, I found each stage very simple to follow. At the end of the 13
minutes’ instruction, I was confident I could do all that had been shown
and I think most school children from the age of about eight or nine
would have been able to tackle the job with similar ease.
5.4
First Word Plus and Ovation were dealt with up to a similar standard;
that is a good basis to begin using them. The full facilities offered by
these sophisticated programs were not all shown, and could not be in the
time available on the video, nor were there any advanced hints and tips
for experienced users.
5.4
My review copy of this video had a fault, causing the picture and sound
to break up for a few seconds, 42 minutes from the start. The tape did
not appear to be physically damaged so this may be a recording fault
during copying which could affect others in the batch. (This was
actually an error on the master tape! However, it has now been cor
rected, I gather. Ed.)
5.4
Data Handling
5.4
Video 3, Data Handling, is nominally 55 minutes long although nearly
five minutes of this is taken up by blank leader tape, titles and
advertising for the other videos in the series.
5.4
It began with an explanation that data handling can include text,
numbers, pictures and sound, followed by a 33 minute look at the various
programs which form Data Sweet. These comprise Data Plot, a graph
program; Data Pick, a data base with text and icons; Data Card, which is
similar to Data Pick but has key words replacing the icons, and Data
Calc, a spreadsheet. They were all demonstrated in enough detail to get
anyone using them. Data Sweet is, however, a very individualistic
package and anyone who had learned to use these programs would find some
marked differences in other integrated programs.
5.4
Immediately after Data Calc there was a brief look at Schema, which was
described as a professional spreadsheet. This took about a minute and a
half, and was a demo rather than tuition, so anyone whose interest is
confined to this program would not find the video worth buying.
5.4
The next nine minutes were devoted to the Squirrel database with
instruction on setting up fields, entering data and searching. Menus
were used throughout and the short cuts offered by function keys were
never mentioned. The tuition was detailed enough for anyone to begin
using the database although it was admitted that this was too sophisti
cated a program to be explained in full. Again, this program has its own
way of doing things which are not the same in other databases.
5.4
The video ended with a two-minute demo of Genesis and a four-minute look
at Magpie, using existing databases and with no attempt to show how to
set up your own.
5.4
Art & Graphics
5.4
Video 4, Art & Graphics, also a nominal 55 minutes, began with a look at
the Technoscan hand scanner. A picture was scanned from a book, cut to
shape and printed and then loaded into Paint to be cleaned up. This was
done by using a white “paint spray” and “pencil” to remove grey marks
from the background. Unfortunately the grey marks were completely
invisible, despite adjusting contrast and brightness on my television
monitor.
5.4
Two programs were then shown in some detail. The first was Revelation
where the use of tools, shapes and colours were demonstrated. A picture
was loaded and manipulated, changing contrast, colours and colour
saturation and even producing a negative image. By that stage, I was
hoping to see a picture actually created but this was not done. As this
is one of the shortest of the four videos there would have been ample
time to show an artist actually using the program to do more than the
doodles which were all we saw produced.
5.4
Poster had a more practical demonstration, with full instruction on
reshaping, sizing and moulding both text and pictures then adding a
border to produce a complete poster.
5.4
Computer aided design (CAD) was limited to three and a half minutes with
an educational program, KiddiCAD, which manipulated blocks of colour.
Then the video ended with a display of pictures from various art
packages, mostly unidentified, which showed the standards which can be
reached by competent artists.
5.4
Who should buy them?
5.4
All the videos have clear, step by step, demonstrations of how to use
the main programs they feature and they will be of most value to new
users of those particular programs. There is probably nothing which is
not in the program manuals but the combination of clear explanations and
demonstrations make the information much easier to understand and
absorb.
5.4
Up & Running is an excellent introduction for beginners, either those
completely new to computing or those who have come to the A3000/
Archimedes range from other micros, including the BBC-B and Master.
Experienced A3000/Archimedes users will find it too elementary, unless
they have not so far used the Edit, Paint and Draw applications.
5.4
Text Processing will be of most value to new or potential users of First
Word Plus, Phases or Ovation. It would also be of use to anyone who is
uncertain whether or not to venture into word processing or desk top
publishing as it shows what these packages can do and how easy they can
be. The standard is too elementary for experienced users of them.
5.4
Data Handling would be of most use to anyone interested in Data Sweet
and for beginners with Squirrel. Schema, Genesis and Magpie are demos
rather that tutorials and it is not worth buying the video just for
them, although their inclusion does help to provide a fairly wide
overall look at data handling.
5.4
Art & Graphics gives a good idea of what can be done with a hand scanner
and an art program, particularly Revelation, but it is not an art tutor
and will not teach you how to create your own Van Gogh. There is a good,
very detailed, explanation of how to use Poster. Parents and schools may
find the look at KiddiCAD a useful extra.  A
5.4

5.4
Tracing and Drawing Conclusions!
5.4
Tord Eriksson & Rob Sherratt
5.4
(Tord sent us a review of David Pilling’s Trace utility which I sent to
Rob Sherratt, our new DTP editor to check out. We then received another
unsolicited review of Trace from Jochen Konietzko which agreed with Tord
and Rob’s conclusions but didn’t really add anything. So here is Tord’s
review followed by Rob’s own comments. Ed.)
5.4
Sprites do not scale very well − any jagged edges get worse if a sprite
is enlarged, just as the original non-outline fonts got worse if you
enlarged them. We call characters like that bit-mapped and pictures made
the same way, sprites.
5.4
The latest way of doing things is doing it as if it were drawn by hand,
by using Bezier curves. A Bezier curve is a mathematical way of
describing twisting or straight lines. This is the method used by !Draw,
!DrawPlus and the Outline Font Manager, because the outline fonts are
exactly that − Bezier Curves.
5.4
The problem has been in making illustrations with !Draw. Any complex
illustration takes an awfully long time, but the result is very small in
terms of bytes used and can be scaled up and down without any problems.
5.4
So normally, for a detailed illustration, !Paint would be used to make a
sprite (which could become many hundreds of kbytes), while for simple
illustrations, like schematics, maps etc. !Draw (or !DrawPlus) is much
more suited.
5.4
Scanners, that are becoming increasingly popular, are also producing
large complex sprites (even if they might be in !Draw sprite format,
i.e. a sprite within a Draw file). The real disadvantage of scanned
sprites is their size − many get too big to be saved directly to disc
and some of them don’t fit even after compression with !Spark or similar
utilities.
5.4
Enter the sprite converter: The Tracer
5.4
There have been sprite converters around for some time for Macs, but
most have been quite expensive and not too successful in converting.
5.4
Archimedes users have two to choose between: Trace 2.02 (Trace, at
£5.99, is available from David Pilling.) and Midnight Tracer (Midnight
Graphics, £60).
5.4
Midnight Tracer doesn’t handle colours and is a bit expensive in
comparison with Trace, even if it is quicker, so I’ll concentrate on
Trace. (Tracer was reviewed in Archive 4.11 p35.)
5.4
The disc is supplied with a number of sprites and draw files (some are
just perfectly converted), a ReadMe file containing a short manual and
Trace itself. The program is written by David Pilling with some help
from Jason Williams.
5.4
The manual covers all aspects of using !Trace and fills three A4 pages
in printed version. The program is so easy to use that the manual is
rarely needed.
5.4
Using Trace
5.4
After double clicking on the icon, the program installs itself on the
icon bar. When you click on this icon two windows will open, one
labelled “Sprite” and one labelled “Draw”. If you drop a sprite onto the
“sprite” window it will resize automatically, but you can set the “zoom”
manually, if you want. Then you only have to open the menu and click on
“Trace” to starts converting the sprite into a Draw object. This is very
computer intensive work, so this is best done on a computer with an
ARM3, as the computer might be busy for a long time.
5.4
To make life simpler, David has added a batch mode where you fill a
directory with sprites and then drop it on the Tracer icon. This starts
batch processing, creating a new directory called Draw in the same place
that the sprite directory came from. This is an ideal job for your
computer to do during the night, as some complex sprites take a long
time to convert, even with an ARM3.
5.4
Conclusion
5.4
I had some problems in the beginning, trying to convert very small
sprites: This was not very successful and gives little or no saving in
terms of kbytes on your hard disc. Being a black and white fanatic, I
mainly tried black and white sprites (scanned photos, drawings etc.).
The result was little short of amazing, especially on big sprites as the
one of the car opposite. The amount of detail is a bit less, but not
much, and you can now manipulate the draw picture in !Draw, !DrawPlus,
Poster, DrawBender etc. As long as the originals are big enough, the
results will be great, although it does fail on some occasions (too
little contrast or too few details).
5.4
Is it worth the money? I think it would be worth £25 if it were to be
sold commercially but you only have to pay £5.99!  A
5.4
(Here are Rob Sherratt’s comments....)
5.4
I fully agree with Tord Eriksson’s conclusions (and I would pay more for
David Pilling’s !Trace than Midnight Graphics !Tracer even though I had
previously bought Midnight Graphics’ !Tracer). I would like to amplify a
couple of things Tord mentioned as well:
5.4
“Jagged edges”
5.4
I am fairly sure these are not a function of !Trace but are instead the
result of anti aliasing of the resulting image when displayed on the
Arc’s screen, or when printed on a low resolution printer. I took two of
Tord’s draw files (generated by !Trace) which appear with “jagged edges”
on the screen, and when scaled and printed on our LaserDirect Hi-Res
they appear almost perfect − no jagged edges at all (see Car opposite).
I doubt if I could say the same for the original sprites. I understand
that David Pilling’s software incorporates “best fit” algorithms which
are specifically designed to smooth out the lack of resolution between
pixels in the original images. This means that the “traced” images are
normally much better than the original sprites..
5.4
Automatic colour sprite / draw conversion
5.4
Just drag the full colour sprite into !Trace’s sprite window and up pops
a full colour !Draw object version of the same in the draw window.
Straightforward images can take just a few seconds with an ARM3. This
automatic conversion of colour (or greyscale) sprites is just not
possible with Midnight Graphics’ Tracer product − and to do the
operation manually using it can take hours! Unfortunately, I couldn’t
test really complex colour sprite conversion with David Pilling’s
program because with my (older) version 2.00, !Trace alerted with the
message “trap occurred while in trap handler” and exited. I believe this
occurred while reaching the free memory limit on my machine. This fault
is most probably fixed in the current version. (Tord was using 2.02 and
Jochen used 2.05 and neither mentioned this problem, so I assume it is
now fixed. Ed.)
5.4
Simple images vs complex images
5.4
There is a danger of asking a program like !Tracer to do the impossible
and process fully toned 256-colour or grey scale images. If you tried
(eg by using !Draw to manually trace each object using bezier curves) to
turn such an image into its components, then you would soon discover
that continuously varying colour images can produce a million or more
tiny component objects, where one component object is a single con
tinuous shape of one “spot” colour.
5.4
If the original image can be pre-processed in some way (e.g. during
photo-electronic scanning) to reduce it to less than 16 greys or
colours, you have reduced the number of objects by a factor of sixteen −
and the resulting draw file will be that much smaller and !Trace will
complete its processing at least 16 or more times more quickly. Even
sprites with 16 colours/greys can be worthless for tracing if they
contain a very “grainy”, or finely shaded, texture. In these cases, the
draw files can be larger than the sprite files from which they were
generated.
5.4
In fact, for full colour DTP work, we use Impression II to draw the
boxes where we want the illustrations and then we cut out and spray
mount colour photos! There isn’t (well, not yet, anyway) an economic way
of electronically scanning, processing, storing and printing A4 full
colour 300 dpi images.  A
5.4
(Rob and his wife Carole have recently started an Archimedes-based DTP
business called EasyCo. It mainly serves Felixstowe and district, and
was prompted initially by the needs of their local church. Rob is also a
full-time software engineer working for a local telecoms company and has
responded to my plea for editorial assistance on DTP matters in Archive.
He is also keen to encourage “mutual support” links with other Archi
medes owners in his locality. He can be contacted on 0394−672292. Ed.)
5.4

5.4
DeskEdit
5.4
Brian Rowlands
5.4
DeskEdit is a wonderful piece of software, written in C, that deserves
to be on everyone’s icon bar. It is multitasking and replaces Edit,
BasicEdit and Twin and all for the very modest price of £25. On
reflection, if it had a spelling checker, I would certainly use it as a
word processor. Thus, one program to do all your daily chores.
5.4
Acorn would do well to promote its use and even provide it free with
each machine it sells. However, as it consumes 300k, compared with just
160k for Edit, memory problems arise on 1M machines when compiling C
source code with it in residence. There are many A310s on the market and
I would think few eager to waste money on RAM expansions.
5.4
Installation
5.4
DeskEdit sits unassumingly on the icon bar ready to serve with a
T(text), B(Basic) or C engraved. A neat dustbin icon can be appended
too. If one wishes, a nice sound module can be incorporated that
provides a more discernible and pleasant alternative to the standard
Acorn bleep prompt. To get a printout, I had to install an Acorn Version
2 printer driver. (See your local dealer or the July 1991 issue of
Archimedes World or Shareware 17.) Customisation of the default settings
and auto loading of files is child’s play.
5.4
Manual
5.4
The 45 page manual was written on the editor which is testament to the
versatility. I found the text succinct, lucid and logically arranged so
that it could be easily read in an hour. Familiarity with Edit will
shorten the learning curve considerably. First reading left me thinking
I had mastered the package. After just a couple of hours trying the
various options out, a warm fuzzy glow came over me and I was all set to
put it to serious use!
5.4
General comment
5.4
The author has mirrored the features found in Edit and, to some extent,
Twin in respect of function key usage, menus and keyboard shortcuts.
However, a lot more is provided − so much so that you wonder how you
ever coped before. The use of the mouse and menus takes away the need to
have to memorise key sequences. With time, and not that much either, the
shortcuts seem natural to use and don’t demand special memory skills. If
need be, a neat on-screen mini-help manual can be displayed which would
certainly assist the faint-hearted.
5.4
Editing
5.4
Many enhancements of the search routines of Edit have been provided and
all to good effect. Undo is there but with the ability to vary the
buffer size. An extra buffer called “Undelete” is available to absorb
text that has been deleted and from which we can extract its contents; a
character, word or line at a time. It even has a clipboard.
5.4
For me, an exciting marker and position finder facility is built into
the software. With the find examples given, it soon becomes apparent
that there are very many uses for this in either long documents or
programs. Consequently, locating specific points or indexing is made so
very simple.
5.4
Macros
5.4
Ten user definable macros are available for each of DeskEdit’s three
languages (Text, Basic, C) and are activated through the ten digit keys
on the numeric keypad. A dialogue box can be called up to view and edit
them. These I found a boon and of great value when writing a program.
Each is 250 characters in size which means complex and lengthy struc
tures can be created.
5.4
Hardcopy
5.4
A truly marvellous set of page and printer control options are included.
They provide the user with margin settings, headers and footers enabling
one to customise output, even date stamp copy. Gone are the dreary days
of standard program printouts. Now an author can be creative and copy
can be catalogued. Everything I wanted was there with clear instructions
on use. One essential improvement that needs adding would be to know
where a page break occurs as text is being typed.
5.4
Basic programs
5.4
Dragging a Basic program onto the DeskEdit icon detokenises it and loads
it into an edit window. Elementary syntax checking is done as you type.
I suppose something is better than nothing. After changes, saving
retokenises the file. What could be simpler? An option exists to load a
program stripped of its line numbers which is fine provided that you are
not one of those people who reference lines using GOTO’s and the like.
If you are, stick with the Basic Editor.
5.4
C programs
5.4
The editor has extra features for use when typing C source code. If you
have been looking for such and were disappointed with Twin and Edit,
look no further. No longer will you wish you could do something since
you will probably find that you now can.
5.4
Auto indent and a simple line syntax checker are provided to bring
clarity to your writing and improve your efficiency. Keyboard shortcuts
are available for moving to the start of either the next or previous
function definition. Don’t expect miracles from the checker, but if it
does do a valuable job and a message window appears whenever it thinks
something is wrong.
5.4
Summary
5.4
If you, like me, use an editor a lot then DeskEdit is a must. My only
reservation is the difficulty of compiling C programs on a 1M machine.
With such a sound pricing structure, Beebug (alias Risc Developments
Ltd) will get more of my business.  A
5.4

5.4
Minerva Systems    Minerva House, Baring Crescent, Exeter, EX1 1TL.
(0392−437756) (421762)
5.4
Morley Electronics     Morley
House, Norham Road, North Shields, Tyne & Wear, NE29 7TY. (091−257−6355)
(6373)
5.4
Pedigree Films Ltd    Unit B11,
Trinity Business Centre, 305 Rotherhithe Street, London  SE16 1EY.
(071−231−6137) (237−5776)
5.4
Ray Maidstone (p22)    421
Sprowston Road, Norwich, NR3 4EH. (0603−407060) (417447)
5.4
RISC Developments Ltd    117 Hatfield
Road, St Albans, Herts, AL1 4JS. (0727−40303) (60263)
5.4
Serious Statistical Software    Lynwood,
Benty Heath Lane, Willaston, South Wirral, L64 1SD. (051−327−4268)
5.4
Simis Ltd    26 Chittys Walk, Keens Park, Guildford, GU3 3HW. (0483−233048)
(235275)
5.4
Software Solutions    Broadway
House, 149−151 St Neots Road, Hardwick, Cambridge, CB3 7QJ.
(0954−211760) (211760)
5.4