Alpha To Coverage - Oculus GO

Development Rendering
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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())
        {