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Microsoft OS/2 SDK PM 08-08-1988

PM LineFractal Program
----------------------

General Description:
--------------------

This program draws self-similar fractals defined by transformations
of the unit interval.  By recursively applying the transformation,
neat drawings result.

Currently you can only choose the built-in transforms.	Click on one
to get that fractal at the current level of recursion.	Choose level
one (from the Fractal attributes dialog box), and one side to the
frame polygon (same dialog box), to see the transformation itself.

Clicking on the left mouse button causes the fractal to go deeper
into recursion, while clicking on the right causes it to come back
out.

In the attributes dialog box you can specify "# sides of polygon",
which is the number of initial segments to which your transform
will be applied.  You always get a regular polygon of the number
of sides you choose.

With the current limited set of transforms, you can still get some
interesting effects by drawing a new fractal on top of old ones
with varying line attributes.

Note that at recursion level n, an m-segment transform will be
	      n
composed of  m	 line segments.  Keep this in mind when playing with
the 5-segment transforms, namely StovePipe and Esses.

The names are, except for Koch (mathematician who proved, I think,
that the Koch curve has infinite arc length when the level of recursion
goes to infinity), weak attempts to describe the basic shape, Esses
being the most far-fetched (sort of like maybe roughly resembling
S-curves on a race track?).


Description of commands:
------------------------

File
    About
	Show the credits.

Transform
    SharkTooth		(2 segments)
    SawTooth		(3 segments)
    Koch		(4 segments, with two segments causing reflection)
    StovePipe		(5 segments, with two segments causing reflection)
    Esses		(5 segments)

	Click on one of these to select a similarity transform for your
	fractal.

Environment
    Clear bitmap
	Clear the bitmap to the background color.

    AutoScale
	If checked, the bitmap will be resized every time you change
	the window size (even if you iconize).

	If not checked, the bitmap will stay the same size and won't
	be redrawn when the window size changes.

    Line attributes ...
	Calls up a dialog box in which you can select the following
	values:

	    line color
	    line style
	    line mix mode

	    bitmap background color

	    # sides to initial polygon

	    number of points sent to GpiPolyLine at a time

	    level of recursion at which to draw

	    whether or not to clear the bitmap between fractals

Control
    Redraw
	Forces the fractal to be redrawn.

    Abort drawing
	Causes drawing of current fractal, if any, to cease.

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