hehe I have now full understand
But maybe it's more practical to see the result as soon as in Moi before to past in the 2D prog ;)

another thing is that artifact normal in the 2d prog image ? corners lines are separated!
(that makes the same of course in Moi ; with the 2 parameters changed :)
here I put 64 , (image is 35 % reducted) :)

Ps and my maxi seems to be 2048 * 2048 (in Moi with the past to clipboard) with a video card with 128 megas : normal?