How to reproduce:
1. Open the “URP_Multi_Camera_Graphics_API_Performance“ project
2. Open the “SampleScene”
3. Open the Game view window and add an additional Game view (right-click on Game view tab > Add Tab > Game)
4. Make sure both Game view windows are visible
5. Make sure one Game view is using “Display 2”
6. Make sure the Game view with “Display 1” has the Rendering Statistics window open (“Stats” button)
7. Enter Play Mode and make sure that the Game view with “Display 1” is focused
8. Observe the Rendering Statistics window
Expected result: moderate performance impact - FPS is reduced by about 15-35%
Actual result: severe performance impact - FPS is reduced by about 50-70%
URP reproduced with: 2022.2.0a11, 2022.3.5f1, 2023.1.4f1, 2023.2.0a23
URP not reproduced with: 2021.3.28f1, 2022.2.0a10
HDRP reproduced with: 2021.3.28f1, 2022.2.0a11, 2022.3.5f1, 2023.1.4f1, 2023.2.0a23
Reproduced on: Windows 10 (by reporter), Windows 11
Not reproduced on: macOS 12 (M1)
Notes:
1. Could not test in Player → could not find a way to render different cameras in different windows in one Player
2. Reproducible in a new project
3. Reproducible with “Direct3D12”, “OpenGLCore”, and “OpenGLES3” Graphics APIs in Universal and HD Render Pipelines
4. Not reproducible with “Direct3D11”, “Vulkan”, and “Metal” Graphics APIs
5. Performance degradation for the HD Render Pipeline is about 40-50% → created a new project with a “3D (HD RP)” template
6. Could not test “OpenGLCore”, and “OpenGLES3” Graphics APIs in the HD Render Pipeline → these Graphics APIs are not supported by the HD RP package
7. Could not test “Metal” Graphics API with 2023.2.0a23 in the HD Render Pipeline → “Compute shader” errors are thrown
8. It seems that before the regression point using the “Direct3D12” Graphics API in the Universal Render Pipeline, the FPS remains stable and in some versions was even slightly better (about 5%) when the second Game view was using “Display 2”
9. Did not reproduce with “OpenGLCore”, and “OpenGLES3” Graphics APIs in the Universal Render Pipeline in the regression point