See http://flea.sourceforge.net/ - a 3D TurtleGraphics implementation, supporting backends from Tk Canvas to PovRay

* http://flea.sourceforge.net/fleaTutorial1.png
* when you edit a flea script in your least-favorite editor, on the left, each time you save a .flea file, the fleaTk module on the right automatically sketches it. Then you pick a back-end renderer and hit Render. See http://wiki.rubygarden.org/Ruby/page/show/FractalLifeEngine/LampTutorial for the complete cycle

* http://flea.sourceforge.net/fleaIvviewSample.png 
* an IView viewer showing umbrellas in IV format - probably OpenInventor

* http://flea.sourceforge.net/leftTropistLamp.png 

* http://flea.sourceforge.net/larch.png 
* the filename says "larch.png", but I think this is a furry fir tree. (I know how to recognize trees from a distance!)

While working on Flea, I explained to my woman I was spending all my spare time "writing a program that generates complex photorealistic shapes, like trees, using short primitive rule sets". Not in so few words. 

She said, "Can't you just download pictures of trees from the Internet?"

''I hope you told her no.  Trees you can find, but when you want a particular type and placement, it can get very difficult.  Even if all I cared about was having something that looked tree-like, and not the underlying principles, I'd be much happier if I could grow my own.''

* http://flea.sourceforge.net/yetAnotherStupidTree.png yet another stupid tree

* http://flea.sourceforge.net/peanoCurve.png this might have been an attempt at a Hilbert curve

* http://flea.sourceforge.net/fishy.png not only trees can flea