Alpha To Coverage - Oculus GO

Development Rendering
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1

Following a lot of experiments in removing aliasing in our Apps i noticed that a significant feature seems to be out of reach.

Alpha To Coverage working with Unity. Also recommended here by John Carmack..

Im looking for tips to enable an already working feature on PC Alpha to Coverage for Oculus Go and Android.
I hope it solves the Problem that all my masked materials alias very significantly (such as foliage).

2

could you find a solution?

3

Here is code i found deep on the Oculus Dev Platforms that allows us to enable Alpha 2 Coverage for Android! So no credits for me please. I updated it for 4.22

Important to note that it increases the cost of masked materials! And there is a Qualcomm forced dithering. It still looks way better, so for some of you it could make sense.

MobileBasePassPixelShader.usf

Line 622
        OutColor.a = Opacity;

 Line 664     
        // CHANGE BEGIN
            #if MATERIALBLENDING_MASKED
                #if OUTPUT_MOBILE_HDR
                    if (GetHDR32bppEncodeMode() != HDR_ENCODE_NONE) // FP16 HDR stores Z in framebuffer alpha
                #endif
                {
                    OutColor.a = GetMaterialMaskInputRaw(PixelMaterialInputs);
                }
            #endif
        // CHANGE END

OpenGLCommands.ccp

Line 1430
            if (RenderTargetBlendState.bAlphaBlendEnable)
            {
                FOpenGL::EnableIndexed(GL_BLEND,RenderTargetIndex);
                glDisable(GL_SAMPLE_ALPHA_TO_COVERAGE); //CHANGE
            }
            else
            {
                FOpenGL::DisableIndexed(GL_BLEND,RenderTargetIndex);
                glEnable(GL_SAMPLE_ALPHA_TO_COVERAGE); //CHANGE

OpenGLDrv.cpp

Line 620
        // Intel HD4000 under <= 10.8.4 requires GL_DITHER disabled or dithering will occur on any channel < 8bits.
        // No other driver does this but we don't need GL_DITHER on anyway.
        glDisable(GL_DITHER);
        
        glEnable(GL_SAMPLE_ALPHA_TO_COVERAGE); //CHANGE
    
        if (FOpenGL::SupportsFramebufferSRGBEnable())
        {