A classic rendering problem in realtime 3D graphics is overlapping transparent surfaces. Well, I recently wrote a shader for Unity that renders alpha transparency with correct depth sorting. My solution isn’t unique, but I don’t see a lot of people talking about it, so hopefully this will help people out.
The depth sorting in this shader still only works well for hard-edged cutouts, but you can mix cutouts with smooth semi-transparency in the alpha channel, and any rendering glitches will be restricted to only the semi-transparent parts. This is a huge improvement over having those rendering glitches apply to the entire model, and hopefully my explanations give you a full appreciation for the tradeoffs being made.Continue reading “Transparency with Depth Sorting”