public override void GenerateShader(MaterialGeneratorContext context)
{
base.GenerateShader(context);
var attributes = context.CurrentMaterialDescriptor.Attributes;
int glassPassIndex = context.PassIndex % 2;
if (attributes.CullMode == CullMode.None)
{
context.MaterialPass.CullMode = context.PassIndex < 2 ? CullMode.Back : CullMode.Front;
}
else
{
context.MaterialPass.CullMode = attributes.CullMode;
}
// Compute transmittance
context.GetShading(this).LightDependentExtraModels.Add(new ShaderClassSource("MaterialTransmittanceReflectanceStream"));
context.Parameters.Set(MaterialTransmittanceReflectanceStreamKeys.RefractiveIndex, RefractiveIndex);
context.MaterialPass.HasTransparency = true;
if (glassPassIndex == 0)
{
// Transmittance pass
context.MaterialPass.BlendState = new BlendStateDescription(Blend.Zero, Blend.SourceColor)
{
RenderTarget0 = { AlphaSourceBlend = Blend.One, AlphaDestinationBlend = Blend.Zero }
};
// Shader output is matTransmittance
// Note: we make sure to run after MaterialTransparencyBlendFeature so that shadingColorAlpha is fully updated
context.AddFinalCallback(MaterialShaderStage.Pixel, AddMaterialSurfaceTransmittanceShading, MaterialTransparencyBlendFeature.ShadingColorAlphaFinalCallbackOrder + 1);
}
else if (glassPassIndex == 1)
{
// Reflectance pass
context.MaterialPass.BlendState = BlendStates.Additive;
}
}