text: IfsCompose
  ----------
  
  IfsCompose is a plug-in for GIMP that allows
  the creation of Iterated Function System fractals by direct
  manipulation onscreen of the component transforms.
  
  
  IFS Fractals
  ------------
  
  You may be familiar with IFS's from the screen
  hack 'Flame'. They are also the basis of fractal image compression.
  
  For a brief introduction to IFS's see Foley and van Dam, et
  al,. _Computer Graphics, Principles and Practice_, 2nd Ed., 
  (Addison Wesley, 1990).
  
  The standard references in the field are Michael Barnsley's books (though
  I haven't looked at them yet):
  
  M. Barnsley, _Fractals Everywhere_, Academic Press Inc., 1988.
  M. Barnsley and L. Hurd, _Fractal Image Compression_, Jones and
  Bartlett.
  
  Briefly, you take a point and repeatedly apply one of a set of
  transformations to it, choosing randomly between them, and plot the
  point at each step. An interesting result (the Collage Theorem) says
  that if you can find a set of transformations that break up an image
  into smaller copies of itself, then the resulting fractal exactly
  reproduces the original image.  For example, here is a classic image
  of a leaf and the same image with the four component transforms
  colored distinctively.
  
  But the best way to appreciate this may to install this program and
  try it out. I've extended the basic concept as found in
  Foley and van Dam to include transformations in color space as
  well as in real space.
  
  Installation
  ------------
  The included Makefile should work with minor modifications on most
  systems if you have installed Gimp normally. Put the resulting binary
  in ~/.gimp/plug-ins or the system-wide plug-ins directory.
  
  The included files gtkaspectframe.c/.h implement a modified frame
  widget that guarantees that the aspect ratio of the child widget
  remains constant when the parent is resized. It's sort of specialized,
  but if you think it would be useful for other purposes, let me know
  and I'll lobby for its inclusion in the standard gtk.
  
  Use
  ---
  The interface is somewhat complex and it may take you a little while
  to get the hang of it. (There are 19 parameters for each
  transformation in your fractal, after all). The best way to learn is
  probably to start by making small changes, and seeing what they
  do. Click on the transformations (represented by polygons) in the
  design window to manipulate them interactively.
  
  Button-1: rotate/scale
  Button-2: distort
  Button-3: move
  
  If you hold down shift while clicking, you can select multiple polygons
  to apply the transformation to.
  
  Try not to click too near the center of a polygon, as this will
  amplify your actions.
  
  Note that if you render onto an image with an alpha channel, the
  background will be transparent (very useful for compositing several
  fractals), otherwise the background will be the current background.
  
  There are tutorials and some example images at:
  
   http://www.gtk.org/~otaylor/IfsCompose/ifs_tutorial/tutorial.html
   http://tigert.gimp.org/gimp/ifs-compose/
  
  
  Have fun!
  
  Owen Taylor
  