[Lichtso]

I read the paper and I am aware that the gaussian projection is an approximation anyway (hence I spoke about ellipsoids, not gaussians). Still, one could at least aim to get the iso contour right and yes using the Jacobian matrix is not unsound, just incomplete. As I said, this approach can not produce the distinctive "wiggle" that you get from rotating an ellipsoid while staring dead center at it.

[porphyra]

True, it is an approximation after all. But it is a useful approximation since the main advantage of Gaussian splatting is the speed.