Resolved MSAA breaks alpha blended rendering

I'm rendering a mesh with MSAAx8 enabled(though the issue occurs at varying severity at x2 and x4). I sample a texture and pass the value from the texture to the color.a returned in the frag. You can see in the screenshots that the result is stepping with MSAA enabled and a clean cut with MSAA disabled.

MSAA on

MSAA off

 

Is alpha to coverage being used?

 

Yep, used in both the shader with the ShaderLab toggle "AlphaToCoverage 1" and attempted in the texture import settings but it changes nothing

 

Well I would blame Alpha to Coverage for causing that problem. It should be disabled and the pass should be opaque not transparent (though I can't see this mattering), for MSAA to function out of the box.

 

Disabling A2C makes the object fully opaque. I'm not sure why that's happening now. Even if I toggle off MSAA, disabling A2C disabled any transparency

 

I am not sure what your desired effect is supposed to be. A2C is best explained by @bgolus here https://bgolus.medium.com/anti-aliased-alpha-test-the-esoteric-alpha-to-coverage-8b177335ae4f

Are you looking to fade complex meshes in and out, or have parts of it transparent yet have the polys sorted correctly?

 

I've worked it out, the banding is due to the 4 levels of alpha afforded by coverage, the bgolus articles shows how to remap the 256 alpha into the coverage correctly

 

Great