slipher
slipher
The depth value as read in the generic shader with depth fade enabled, with the color formula `1 / (1.0001 - depth) / 600`.  I don't think those low...
Happens regardless of bindless texture (or material system) settings. I tried putting `glMemoryBarrier( GL_ALL_BARRIER_BITS )` in Tess_End and that didn't fix it. Since I didn't note the GPU model yet...
I tried putting a call to `glTextureBarrier()` in Tess_End and that fixes it. This function requires the `ARB_texture_barrier` extension. Maybe we could call that only before shaders that use the...
Although `TextureBarrier` worked in practice, I don't think it stops the undefined results according to the standard. From OpenGL 3.2 section 3.8.9 "Texture Minification: > __Rendering Feedback Loops__ If all...
Hmm I don't see any way of getting past the "feedback loop" rules without creating a copy of the depth buffer, so I guess I'll go with the texture barrier...
Oh I bet it's the `polygonOffset` that triggers the bug. That could involve a different GPU code path for writing the depth. Unless it's just the different shader sort that...
> No, using `glTextureBarrier()` is correct: > 9.3.1 Rendering Feedback Loops: Yeah, there's that section about exceptions where a texture *write* is not undefined. But it doesn't say anything to...
Fix is now in. But I will note that with material system enabled, the depth values can be bad with any old surface -- it doesn't have to be polygonOffset....
The collision geometry of the offending patch surface can be visualized by setting `/surfSC 437` on my [branch](https://github.com/slipher/Unvanquished/tree/trace-research):  I thought decreasing `SUBDIVIDE_DISTANCE`, which is supposed to produce more precise...