Implement dither transparency as one solution for order independent transparency

[mvaligursky]

Not a general solution, but cheap and useful.
https://danielilett.com/2020-04-19-tut5-5-urp-dither-transparency/

[querielo]

I'm not sure that it has to be a part of the engine since it can be done without it. Also, it is not clear what kind of pattern should be used: Bayer, white noise, blue noise and so on.

Example.

Source code: https://github.com/querielo/playcanvas-dither-transparency

Project: https://playcanvas.com/project/1051789/overview/dither-transparency

[LeXXik]

Is the project private?

[querielo]

Ouch. I forgot about it :-)

Fixed.

https://playcanv.as/p/qdYtm4jw/
https://playcanvas.com/project/1051789/overview/dither-transparency

I thought also about influencing on shadow map (so, we get shadows for transparent objects with usage noises/patterns). But I need to understand where to place discard into the shadow pass code.

It looks like impossible without rewriting/changing the internal _fsGetShadowPassCode function.

[yaustar]

I'm not sure that it has to be a part of the engine since it can be done without it.

IIRC, the goal was to have a script that was officially supported by PlayCanvas rather than adding it to the engine directly. So it would live here: https://github.com/playcanvas/engine/tree/main/scripts

[mvaligursky]

Script vs in engine is not something that was decided yet, it can go either way.