So I'm trying to build a spherical distortion function, because I have a "Proceduaral Ball" and I want to wrap a procedural texture of dimples (Golf) or Nubs (Basketball) or scratches or seams (Soccer) around the ball. Except at the polar coordinates it gets pinched.

So I found a couple of threads that illustrate the idea:

http://gis.stackexchange.com/questions/28390/how-does-one-calculate-distortion-on-equirectangular-projection

And the Math Behind projections : http://paulbourke.net/geometry/transformationprojection/

But I can't quite put my finger on if doing a FX Map is the right pathway, as it doesn't deal with value sampling and the "Math" of how to distort the image, but the Pixel Processor has no concept of where on the map it is currently.

Someone maybe suggest a workflow, and I'll share the Function with everybody, once I get it working.

So I found a couple of threads that illustrate the idea:

http://gis.stackexchange.com/questions/28390/how-does-one-calculate-distortion-on-equirectangular-projection

And the Math Behind projections : http://paulbourke.net/geometry/transformationprojection/

But I can't quite put my finger on if doing a FX Map is the right pathway, as it doesn't deal with value sampling and the "Math" of how to distort the image, but the Pixel Processor has no concept of where on the map it is currently.

Someone maybe suggest a workflow, and I'll share the Function with everybody, once I get it working.