a curious shape indeed.
this morning I was looking for things to show during my upcoming workshop so I was roaming around on flickr and found eskimoblood’s profile & work.
I found the spidron tests he did exetremely interesting and wanted to know a bit more.

and there is more !
http://edan.szinhaz.org/SpidroNew/general_concept.htm
funnily enough, it was invented by a hungarian just like the L-system of my last article :)
the explainations are quite straight forward and I could build a model in less than an hour which is unfrequent.

actually the rule they use gave me pretty odd results : an angle of 30 degrees gives an isocele triangle’s side that doesn’t reaaly work or at least that is not flexible at all…
after tweaking a bit I got it to work with a start angle of 35.3535353535°… instead of 30°
there has to be a reason.

the good thing is that the base shape can be tiled so when you put it in circle, you’d get this.

as it can be tiled, we can get this tiling

where the white outlines show each spidron and this randomly colorized tiling

the base shape is made of 2 triangles and Flash likes triangles so it’s also possible to map a picture

and that’s where I fucked it up but I found it cool :)

btw the grain on some pictures is obtained dynamically by this quick and dirty method:

public function fastGrain( input:Bitmap, scale:Number = 1, alpha:Number = 1, greyscale:Boolean = false, smooth:Boolean = true ):void
{
	if( scale > 1 ) scale = 1;
	var bd:BitmapData = input.bitmapData.clone();
	bd.perlinNoise( 5, 5, 1, Math.random() * 0xFFFFFF, false, true, 7, greyscale );
	input.bitmapData.draw( bd, new Matrix( 1 / scale, 0, 0, 1 / scale ), new ColorTransform( 1,1,1, alpha ), BlendMode.OVERLAY, null, smooth );
}

you should import the necessary classes, the rest is rather self explainatory :)

if you’d like to understand tiling further, pixelero did a good article about it.
there’s also this wikipedia page

more and bigger pictures on my flickr page
that was it :)

Tags: geometry, grain, graphics, tiles, tiling