public virtual void Visit(MaterialGeneratorContext context)
{
// If not enabled, or Material or BlendMap are null, skip this layer
if (!Enabled || Material is null || BlendMap is null || context.FindAsset is null)
{
return;
}
// Find the material from the reference
var material = Material.Descriptor ?? context.FindAsset(Material) as IMaterialDescriptor;
if (material is null)
{
context.Log.Error($"Unable to find material [{Material}].");
return;
}
// Check that material is valid
var materialName = context.GetAssetFriendlyName(Material);
if (!context.PushMaterial(material, materialName))
{
return;
}
try
{
// TODO: Because we are not fully supporting Streams declaration in shaders, we have to workaround this limitation by using a dynamic shader (inline)
// Push a layer for the sub-material
context.PushOverrides(Overrides);
context.PushLayer(BlendMap);
// Generate the material shaders into the current context
material.Visit(context);
}
finally
{
// Pop the stack
context.PopLayer();
context.PopOverrides();
context.PopMaterial();
}
}
public override void GenerateShader(MaterialGeneratorContext context)
{
// Exclude ambient occlusion from uv-scale overrides
var revertOverrides = new MaterialOverrides();
revertOverrides.UVScale = 1.0f / context.CurrentOverrides.UVScale;
context.PushOverrides(revertOverrides);
context.SetStream(OcclusionStream.Stream, AmbientOcclusionMap, MaterialKeys.AmbientOcclusionMap, MaterialKeys.AmbientOcclusionValue, Color.White);
context.PopOverrides();
context.SetStream("matAmbientOcclusionDirectLightingFactor", DirectLightingFactor, null, MaterialKeys.AmbientOcclusionDirectLightingFactorValue);
if (CavityMap != null)
{
context.SetStream(CavityStream.Stream, CavityMap, MaterialKeys.CavityMap, MaterialKeys.CavityValue, Color.White);
context.SetStream("matCavityDiffuse", DiffuseCavity, null, MaterialKeys.CavityDiffuseValue);
context.SetStream("matCavitySpecular", SpecularCavity, null, MaterialKeys.CavitySpecularValue);
}
}
public void Visit(MaterialGeneratorContext context)
{
if (!Enabled)
{
return;
}
// Push overrides of this attributes
context.PushOverrides(Overrides);
// Order is important, as some features are dependent on other
// (For example, Specular can depend on Diffuse in case of Metalness)
// We may be able to describe a dependency system here, but for now, assume
// that it won't change much so it is hardcoded
// If Specular has energy conservative, copy this to the diffuse lambertian model
// TODO: Should we apply it to any Diffuse Model?
var isEnergyConservative = (Specular as MaterialSpecularMapFeature)?.IsEnergyConservative ?? false;
var lambert = DiffuseModel as IEnergyConservativeDiffuseModelFeature;
if (lambert != null)
{
lambert.IsEnergyConservative = isEnergyConservative;
}
// Diffuse - these 2 features are always used as a pair
context.Visit(Diffuse);
if (Diffuse != null)
{
context.Visit(DiffuseModel);
}
// Surface Geometry
context.Visit(Tessellation);
context.Visit(Displacement);
context.Visit(Surface);
context.Visit(MicroSurface);
// Specular - these 2 features are always used as a pair
context.Visit(Specular);
if (Specular != null)
{
context.Visit(SpecularModel);
}
// Misc
context.Visit(Occlusion);
context.Visit(Emissive);
context.Visit(SubsurfaceScattering);
// If hair shading is enabled, ignore the transparency feature to avoid errors during shader compilation.
// Allowing the transparency feature while hair shading is on makes no sense anyway.
if (!(SpecularModel is MaterialSpecularHairModelFeature) &&
!(DiffuseModel is MaterialDiffuseHairModelFeature))
{
context.Visit(Transparency);
}
context.Visit(ClearCoat);
// Pop overrides
context.PopOverrides();
// Only set the cullmode to something
if (context.Step == MaterialGeneratorStep.GenerateShader && CullMode != CullMode.Back)
{
if (context.MaterialPass.CullMode == null)
{
context.MaterialPass.CullMode = CullMode;
}
}
}