How to progressively map a plane to a semisphere?

[RobA]

filter rel2ellv3(image in)
xprime=x/sqrt(1-4*(y/H)*(y/H));
yprime=y/sqrt(1-4*(x/W)*(x/W));
in(xy:[x+t*(xprime-x),y+t*(yprime-y)])
end

I haven't tried it, though.

I tried it. works brilliantly!

Good job.

-Rob A>

[PhotoComix]

filter rel2ellv3(image in)
xprime=x/sqrt(1-4*(y/H)*(y/H));
yprime=y/sqrt(1-4*(x/W)*(x/W));
in(xy:[x+t*(xprime-x),y+t*(yprime-y)])
end

I haven't tried it, though.

@Isomage

I did try...perfect ! ...exactly what i was looking for, thank a lot (and thanks for all the other contribute )

PS the image you posted as example was strange but the code work well !

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About animation gif has to low quality for my taste, but gimp (with a AVI plugin, or with GAP ) may save as uncompressed AVI, then is quite simple apply a codec to shrink the file size or convert to FLV

[RobA]

I exported it as an AVI using the AVI plugin (which uses some really funky codec... if anyone uses it, one tip is to make sure your image size is divisible by 2 in both directions).

virtualdub would read it, so I piped it through avisynth, then used virtual dub to convert it to a divx.

In you are interested, the result is here:
http://ffaat.pointclark.net/incoming/test-divx.avi

-Rob A>

[PhotoComix]

there is a even better way to save a animation:
simply export all layers as PNGs (GAP may do it,as several scripts)

Then are a lot of free SW (one for Win is SUPER) that may convert that in AVI or in other Video format,with no more effort then a couple of clicks

thank for the test, yes if what i was looking for, i will do a bit slower and maybe with some loops