Nonlinear projection (e.g., fisheye camera)

[jwwalker]

In the OpenGL world, I've done some experimentation with fisheye and all-seeing cameras, which use a nonlinear projection. That doesn't play very well with the linear interpolation between the vertex shader and the fragment shader. So I've used a geometry shader to subdivide triangles that were too big in screen space. How would you handle something like that in Filament? I suppose one alternative would be to do offscreen renders to create a cube map texture on the fly, and then transform that in the fragment shader. But it seems like rendering everything 6 times would inevitably be a performance problem.

[romainguy]

More importantly this kind of projection might not be compatible with our lighting system.

[romainguy]

@pixelflinger