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Heres a nice extension thats easy to use, everything you need to know is
in the following doc file. If you use it a lot or just like it don`t
forget it`s shareware........Steve
============================================================================
This file is freely distributable in its original archive, provided no profit is involved.
It may not be distributed on a cover disk.
The archive should contain the following files:-
stars.doc (this)
stars.lib
starspro.lib
stars.lib.info
starspro.lib.info
Seperate distribution of these files is forbidden.
All files are copyright 1993 J.G.Doig, and may not be modified in any way, without
prior written consent.
AMOS Stars Extension V2.23b. **SHAREWARE VERSION**
By Jason G Doig
Introduction.
Stars is an Amos (and AmosPro) system extension, that provides many new
commands to the Amos instruction set.
Installation.
My apologies for the lack of an installation script, this is being written very late the
night before I leave for a short holiday, and I simply do not have time right now.
To install the Extension, load workbench and find the relevant file:-
'stars.lib' for Amos 1.3
'starspro.lib' for AmosPro
You will then need to copy this to the relevant system drawer, either "amos_system"
or "ap_system". Now boot up Amos, and use the configuration program supplied
with Amos to set the loaded extensions.
Type the path of the of the stars library into location #20. To see what the necessary
file path is, simply look at the early positions in the extenrion list, as the standard
system extensions are in the same place as you have just put stars.lib.
Now reboot Amos.
Please work with a copy of your normal boot disk, as if you give an incorrect path,
then Amos may refuse to boot.
Please mail me if you have any problems.
Commands
The commands are as follows:-
STARS BLAST
Does a fancy fade effect on the current screen.
STARS VBL
Does the same as WAIt VBL, but shows idle processor time.
The following are the actual starfield commands. These plot stars, under interrupt
onto a given screen. Please note that these plot not in a specific colour, but straight
onto the last bitplane of a screen, so please try to keep this clear or it will get
corrupted. The easiest way to put stars on a screen is to have one plane more than
you actually use. So use a 32 colour screen to display a 16 colour logo. Then copy
the first half of the palette to the second. Change the respective upper colour where
you want stars to show through. e.g. Change Colour, to show through colour 0 on
our example above.
STARS ON screen,direction,number
Displays [number] stars, traveling in a specific direction, on screen [screen]
Only one screen can have stars at one time.
The maximum number of stars is 128
The directions are:-
0 Left
1 Right
2 Up
3 Down
4 Stationary
STARS OFF
Switches off the stars and removes them.
STARS DIR direction
Changes the direction of the current starfield
The next few commands complement the built in COP commands. See the manual
for details.
COP PALETTE a TO b,address
Reads 12bit colours from memory, and builds o copper list to put these colours in
palette registers a to b. a and b can be in the range 0-255, but a < b.
A colour takes up one word.
COP TRUE PALETTE a TO b,address
This is the same as above, but takes colour in the form Red Byte, Green Byte, Blue
Byte, ie. 24bit.
A colour therefore takes 3 bytes.
=COP CURRENT
Returns the address the copper list is currently being built at. This makes poking
straight into it easier.
Look out for my friend Gary's forthcoming game, which uses these and the extra
commands found in the full version of stars.
The extra commands include:-
COP SCREEN, which sets up a copperlist for a whole screen (in an AGA mode if
you want!)
STARS RAIN, which builds multiple 24bit Rainbows.
register now for these and more!
All stars commands will also work on non-aga machines (or have equivalents which
do the same job).
j
5
22
To register your copy send £10 to:-
Jason G Doig
20 Queens Crescent
Kinghorn
Fife
KY3 9RG
Please feel free to contact me with comments, suggestions or bug reports.
I can also be contacted term time, by E-Mail : JasonD@uk.ac.hw.cee
Upgrades will be sent out to registered users only. (although feel free to ask for
more details on the current version before you register - unregistered users should
send an SAE).
Please note that the AmosPro extension requires AmosPro V1.1, due to a bug in
Amos. The updater should be available where you obtained this archive.