Is anisotropic filtering standardized by the D3D or OpenGL specs now? I know in the last decade or so, it was still the case that if you did an image diff of th

Is anisotropic filtering standardized by the D3D or OpenGL specs now? I know in the last decade or so, it was still the case that if you did an image diff of the same scene being rendered with say, 8xAF on both NVIDIA and AMD GPUs, the result would be different since both vendors used a mix of heuristics to get good results. I'm guessing they might've dropped the hacks by now and converged on a known 'good' algorithm. I wouldn't be surprised if mobile GPUs are still cheating even if desktop ones have stopped, though, so you'd be able to detect that with WebGL. There's also the 'detect driver bugs' approach since there are test suites out there that detect various driver stack bugs using special shaders, you could run a set of those to identify the GPU (or even driver) being used to rasterize the WebGL content.