How to progressively map a plane to a semisphere?

[isomage]

I failed to find the discussion on the formula to be applied but if may help i have as Mathmap code

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

I've just had a brief look at mathmap's documentation and examples, and it appears to be able to do animations; as far as I can tell, if you use a "t" parameter it will automatically generate an animated gif (see http://www.complang.tuwien.ac.at/sch...map/anims.html and http://www.complang.tuwien.ac.at/sch...tml#animations). So assuming your xprime, yprime transformations work correctly in mathmap to give your final image, then I'd guess you might be able to get your desired animation with this:

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.

[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