What is ScriptableRenderer.Execute().UpdateReflectionProbeAltas() and why is it taking so much GPU

Hi,

I am wondering what is ScriptableRenderer.Execute().UpdateReflectionProbeAltas(), I have no reflection probes in the scene and disabled skybox reflections in the Lighting Settings.

I am drawing a bunch of sprites as in the second picture and it doesn’t seem to take nearly as much GPU. The sprites are drawn with a Sprite Renderer using a URP Lit Material in 3D Space.

I have tried changing materials to the standard Unity URP>Lit material, the issue still occurs but ScriptableRenderer.Execute().UpdateReflectionProbeAltas(), still uses about a 3rd of the shown GPU usage. Using a standard sprite shader removes this problem all together.

I tried looking through the source code but I don’t have much understanding of the URP Runtime scripts.

I tried making the sprites Opaque and it didnt make a different. I am using Unity 2022.3.36 URP. The difference in the CPU graph comes from testing with Deep Profiling on (left) and off (right).

After some more testing, I think it may be an Editor Only Issue which does reduce the severity of it. I multiplied the number of characters by 4x and ScriptableRenderer.Execute().UpdateReflectionProbeAltas() uses 4x the GPU Usage at 45ms. I wouldn’t mind still trying to fix this in the editor if possible.

However, performance is great in the build → I can’t see GPU usage of the build in the profiler but I am confident by looking at the 120FPS) in my build and the profiling of CPU Usage that it is mostly code using the frame time.

Thanks

I’m still having this issue