Search Issue Tracker
Fixed in 2020.2.X
Fixed in 2019.4.X, 2020.1.X
[Vulkan] Alpha channel is modified when copying between two RGBAFloat textures in compute shader and RGB channels are unused
1. Open the attached project ("case_1227481-VulkanRepro.zip")
2. Open the repro scene ("Scene")
3. Inspect the gradient texture generated by compute shader
4. In Hierarchy, select Main Camera
5. In Inspector, find "Test Renderer (Script)" component
6. Change "Copy Mode" to "Alpha Only"
Expected result: Alpha channel should remain unchanged, as it was copied
Actual result: Alpha channel data changes (game view becomes black)
Reproducible with: 2018.4.20f1, 2019.3.7f1, 2020.1.0b4, 2020.2.0a5
Not reproducible with: 2017.4.39f1
1. The issue reproduces on Vulkan graphics API
2. The issue does not reproduce on DX11, DX12 graphics APIs
3. If _CopySource type in TestCompute.compute is changed to Texture2D<float4>, alpha works as expected.
4. The issue happens only for B and A channels - if R or G are preserved instead, they work as expected.
5. Alpha is probably not really zeroed - in more complex cases channels are modified, but still based on default values (e.g. color shift, value range change).
All about bugs
View bugs we have successfully reproduced, and vote for the bugs you want to see fixed most urgently.
- Curves Editor crops big values
- Building Unity editor via CI results in "System.IO.IOException: Sharing violation on path" error
- MissingMethodException in Player.log when calling Type.GUID in IL2CPP Build
- [Editor] Side panel and graph divider gets stuck when dragged after selecting transition from Any State in Animator Window
- [UI] Color picker tool is stuck in the pixel sampling stage