Search Issue Tracker
By Design
Votes
1
Found in
4.3.1f1
Issue ID
582978
Regression
No
Background sprite can be visible when it shouldn't (due to alpha)
To reproduce:
1. Open attached project
2. Open scene "Game". It contains three sprites - a flower with alpha on it's edges, a grass sprite and a background sprite with white edges
3. In play mode, notice how the white edges of the "BG" sprite are visible on the shadow parts of the flower (alpha) even though there is a sprite covering the "BG"
4. Move the flower away - the lines are no longer visible
Comments (1)
Add comment
All about bugs
View bugs we have successfully reproduced, and vote for the bugs you want to see fixed most urgently.
Latest issues
- Unity CIL Linker fails on Player build when persistent listeners have "<" and ">" in their XML attribute names
- ”Lighting data asset ‘LightingData’ is incompatible with the current Unity version…” warnings are thrown when saving Indoors (URP) and Outdoors (URP) Scenes as Scene Templates
- [iOS] The screen blinks when transitioning from custom to Unity splash screen
- [macOS] ”Ignoring depth surface load action as it is memoryless” warnings are thrown when taking Game View Snapshot
- UI Builder Inspector scrolls back up when changes on an expanded but not fully displayed Inspector tab are saved
TomasJ
Mar 26, 2014 10:46
The alpha issue isn't exactly a bug, but a way Unity does blending. This happens because textures are not with premultiplied alpha.
You can work around in one of the following ways:
- Duplicate the desired shader and change blending to "Blend SrcAlpha OneMinusSrcAlpha, One OneMinusSrcAlpha" - this will set different blending mode for alpha, but might not be supported on some mobile GPUs.
- Duplicate the desired shader and emulate premultiplied alpha:
-- Set blending to "Blend One OneMinusSrcAlpha"
-- Multiply RGB by alpha in the pixel shader (final.rgb *= final.a)