I'm working on screen space shadows in an OpenGL/C++ renderer, and I've been having this weird erroneous shadowing artifact. Here's a video of the artifact in action. Notice how the screen space shadows that I want to see are rendering correctly, just with a lot of artifacts on top. This means ther…

In the end I worked around this as follows:

1) I set  “precision highp float; ” in my shader, so that it uses 32 bit, even on OpenGL ES

2) Then, to improve the performance, I first render to a smaller texture FBO, then scale it up to the screen