3D Alpha rendering bug

[Niedzwiedzw]

Bevy version

0.7

Operating system & version

Linux niedzwiedz-pc 5.15.28-1-MANJARO #1 SMP PREEMPT Fri Mar 11 14:12:57 UTC 2022 x86_64 GNU/Linux

What you did

https://github.com/Niedzwiedzw/bevy-alpha-rendering-bug-showcase

What you expected to happen

boxes shouldn't change the way they're overlapping based on camera position

What actually happened

https://github.com/Niedzwiedzw/bevy-alpha-rendering-bug-showcase

Additional information

[superdump]

You’re setting something that is using an opaque colour as transparent by setting AlphaMode::Blend. Transparent objects are rendered back to front ordered based on the model’s origin in view space. What you show in the clip is expected behaviour. Don’t mark opaque objects as transparent. Or actually use a transparent material on a transparent object and then there are known limitations to the current approach to transparency and an order-independent transparency method may help with that but there is not one implemented yet in bevy.

[superdump]

See here for more details of the limitations of transparent rendering as it is: #2223

[Niedzwiedzw]

ok that makes sense - I have managed to fix it in my - more complex case - where I noticed the problem by setting AlphaMode::Mask(0.5).

https://user-images.githubusercontent.com/22037927/163709426-cf449d30-cbb8-486c-b553-da52ba4ac1ec.mp4
as you can see textures CAN be transparent but they not always are. I think we can close this, but what we could do is add a partially-transparent texture example