Minor nit — in what way do splats render differently depending on direction of looking? To my mind these are probabilistic ellipsoids in 3D (or 4D for motion splats) space, and so while any novel view will see a slightly different shape, that’s an artifact of the view changing, not the splat. Do I understand it (or you) correctly?
Basically for each Gaussian there is a set of coefficients and those are used to calculate what color should be rendered depending on the viewing angle of the camera. And the SH coeffs are optimized through gradient descent just like the other parameters including position and shape.
