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1996-09-26
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This is !Trees, version 1.1 (27 March 1996)
Intro
=========
This is essentially a vector program, with which you can
create drawfiles, depicting a great variety of trees. It accomplishes this
using a fractal method. The resulting drawfiles can be used in all sorts of
DTP work, and also can be further manipulated, in other art programs. While
the intention was to produce trees that looked fairly convincing, it is
possible to achieve results ranging from this ideal to very weird!
Fractal Technique
=================
A procedure is called that contains its' self. This could cause it to go
into an infinite loop. However a paramater called depth is set, which is
lowered each time the loop winds down, and when it reaches 0, it breaks out.
In this program the loop simply draws a line, at an angle from the last
line.
In order to draw a tree from this simple mathematical idea, the fractal
procedure is called several times normally, so that the branches are drawn
with some sort of order.
Memory
======
The process described above, is written in a fairly compact bit of code, but
the looping uses enormous amounts of memory, and takes a long time! In
particular the most memory hungry operations are those using a high value
for depth and canopy thickness. Foliage, particularly weeping foliage is
also memory hungry.
My A5000, with 4Mb of RAM can easily run out of memory, if too many of these
features are turned up! I suspect that users of ARM2 machines will also find
more complicated tasks, very slow.
Using the program
==================
The program is started in the usual way, by installing the !Trees icon on
the icon bar. Double clicking on this opens the tree generator window. A
series of paramaters and variables are already set. To generate a tree
simply click on the Draw icon. A screen will open after a period of time,
with the tree drawn on it.
As the program generates full colour a 256 colour mode such as 28, 40 or 16
is preferable.
The tree picture can be saved as a drawfile, by pressing F3 or from the menu
obtained by clicking the menu button over the tree window. These files can
be large, but if you clik menu over the Tree Generator window, you can save
the tree data as a script file that can be used to generate a similar teee
in the future.
Acorn's !Help application is supported by the program.
The controls
============
It is not easy to achieve the style guide aims of making the controls
intuitive, in this program, so I strongly recommend that users use it in
conjunction with Acorn's !Help application, that !Trees supports.
Tree Types: Three types are offered. I suggest you try them to see the type
of tree form that they offer.
Foliage: The foliage, and weeping options offer the user the ability to add
greenery. The green consists of little circles, and will probably not
normally pass as individual leaves, but they do give an interesting effect.
Tree Paramaters: The first four are paramaters that affect all trees.
Remember that Canopy Density, when made high is memory, and processor
hungry.Twig production affects the proportion of the side branches to the
central stem.
Poplar Height & Pollard Boughs only relate to those two tree types.
Random Variation: The paramaters here can be used to break the symmetry of
the trees. They look more natural. When these figures are high, the tree
looks more chaotic, and can get, very mis-shapen. These paramaters don't
affect memory a lot, so let your imagination rip.
Depth: Everything else depends on this. The higher it is, the amount of
processing escalates. The maximum depth is set at 6.
The Icons:
The paramaters are normally changed with the litle arrows,(bump icons).
Silly numbers cannot be entered this way. However for those who insist on
pushing beyond the limits, the icons are writeable. Believe me it is
possible to occupy too much memory, without resorting to this approach.
TreeScript Files
================
To load it drag any of the script files on to either the icon bar icon, or
the Tree Generator window.
TreeScript files are ordinary textfiles. These can be edited, using a text
editor, but no check is made for over optimistic paramaters, or illegal
ones!
Art
===
This program creates DrawFiles. These are good in many circumstances. The
TreeFiles can be very big, and for more realistic artwork, and manageable
filesizes it will be easier to capture the image as a sprite, using paint,
in order to use a BitMap program to edit it. Superb effects are possible, by
air brushing on leafy textures, and smudge filters, can be impressive in
this context.
Copyright
=========
This program is Public Domain. It may be distributed or copied freely as
long as no part of this software may is used in any other program, whether
commercial or public domain, without my prior written consent, though any
files created by this software are not bound by this condition. This
software may not be distributed for a profit, save that required to cover
packaging and media costs..
Copyright (©) is retained by the author, who may be contacted at the address
beneath. No liability can be accepted by the author for any loss or damage
arising from use or misuse of this software.
Credits
=======
Please read this file, which is located by double clicking over the !Trees
icon, in the filer window, while pressing the <shift> button.
-----------------------------------------------------------------------------
Any improvements or bugs, please report to :-
Robert Seago.
40 Alton Park Road
Clacton On Sea
Essex.
CO15 1ED