#else // ! _MATERIAL_FEATURE_COAT
// For iridescence, we will reuse the recompute per light keyword even when not vlayered.
// When vlayered and iridescence is on, iridescence is also automatically recomputed per light too,
// so the following gives the recompute option for iridescence when NOT vlayered:
#ifdef VLAYERED_RECOMPUTE_PERLIGHT
# if _MATERIAL_FEATURE_IRIDESCENCE
# define IRIDESCENCE_RECOMPUTE_PERLIGHT
# endif
#endif
# undef VLAYERED_RECOMPUTE_PERLIGHT
# undef VLAYERED_USE_REFRACTED_ANGLES_FOR_BASE
# undef _MATERIAL_FEATURE_COAT_NORMALMAP // enforce a "coat enabled subfeature" condition on this shader_feature
bsdfData.bitangentWS = bitangentWS;
}
void FillMaterialIridescence(float mask, float thickness, float ior, inout BSDFData bsdfData)
{
bsdfData.iridescenceMask = mask;
bsdfData.iridescenceThickness = thickness;
bsdfData.iridescenceIor = ior;
}
void FillMaterialCoatData(float coatPerceptualRoughness, float coatIor, float coatThickness, float3 coatExtinction, inout BSDFData bsdfData)
{
bsdfData.coatPerceptualRoughness = coatPerceptualRoughness;
FillMaterialAnisotropy(surfaceData.anisotropy, surfaceData.tangentWS, cross(surfaceData.normalWS, surfaceData.tangentWS), bsdfData);
}
if (HasFeatureFlag(surfaceData.materialFeatures, MATERIALFEATUREFLAGS_STACK_LIT_IRIDESCENCE))
{
FillMaterialIridescence(surfaceData.iridescenceMask, surfaceData.iridescenceThickness, surfaceData.iridescenceIor, bsdfData);
}
if (HasFeatureFlag(surfaceData.materialFeatures, MATERIALFEATUREFLAGS_STACK_LIT_COAT))
{
FillMaterialCoatData(PerceptualSmoothnessToPerceptualRoughness(surfaceData.coatPerceptualSmoothness),
// for it (hence the name iblF in Lit). Here, we will fold all data into
// lobe-indexed arrays.
// For iridescence, to avoid recalculation per analytical light, we store the calculated
// iridescence reflectance that was used (as an approximation to "iridescent pre-integrated" FGD)
// to calculate FGD with the precalculated table:
float3 fresnelIridforCalculatingFGD;
// For clarity, we will dump the base layer lobes roughnesses used by analytical lights
// here, to avoid confusion with the per-vlayer (vs per lobe) vLayerPerceptualRoughness
// Update energy
R12 = F_Schlick(bsdfData.fresnel0, ctiForFGD);
if (HasFeatureFlag(bsdfData.materialFeatures, MATERIALFEATUREFLAGS_STACK_LIT_IRIDESCENCE))
{
if (bsdfData.iridescenceMask > 0.0)
{
//float topIor = bsdfData.coatIor;
// TODO:
// We will avoid using coatIor directly as with the fake refraction, it can cause TIR
// which even when handled in EvalIridescence (tested), doesn't look pleasing and
// creates a discontinuity.
float scale = clamp((1.0-bsdfData.coatPerceptualRoughness), 0.0, 1.0);
float topIor = lerp(1.0001, bsdfData.coatIor, scale);
R12 = lerp(R12, EvalIridescence(topIor, ctiForFGD, bsdfData.iridescenceThickness, bsdfData.fresnel0), bsdfData.iridescenceMask);
}
}
T12 = 0.0;
#ifdef VLAYERED_DIFFUSE_ENERGY_HACKED_TERM
// Still should use FGD!
iblN[0] = iblN[1] = N[0];
} // ...no anisotropy
float3 f0forCalculatingFGD = bsdfData.fresnel0;
if (HasFeatureFlag(bsdfData.materialFeatures, MATERIALFEATUREFLAGS_STACK_LIT_IRIDESCENCE))
{
float topIor = 1.0; // Air on top, no coat.
if (bsdfData.iridescenceMask > 0.0)
{
preLightData.fresnelIridforCalculatingFGD = EvalIridescence(topIor, NdotV[0], bsdfData.iridescenceThickness, bsdfData.fresnel0);
f0forCalculatingFGD = lerp(bsdfData.fresnel0, preLightData.fresnelIridforCalculatingFGD, bsdfData.iridescenceMask);
}
}
// IBL
// Handle IBL pre calculated data + GGX multiscattering energy loss compensation term
bsdfData.fresnel0,
f0forCalculatingFGD,
preLightData.specularFGD[BASE_LOBEA_IDX],
diffuseFGD[0],
specularReflectivity[BASE_LOBEA_IDX]);
bsdfData.fresnel0,
f0forCalculatingFGD,
preLightData.specularFGD[BASE_LOBEB_IDX],
diffuseFGD[1],
specularReflectivity[BASE_LOBEB_IDX]);
// --------------------------------------------------------------------
// TODO: Proper Fresnel
float3 F = F_Schlick(bsdfData.fresnel0, savedLdotH);
if (HasFeatureFlag(bsdfData.materialFeatures, MATERIALFEATUREFLAGS_STACK_LIT_IRIDESCENCE))
{
float3 fresnelIridescent = preLightData.fresnelIridforCalculatingFGD;
#ifdef IRIDESCENCE_RECOMPUTE_PERLIGHT
float topIor = 1.0; // default air on top.
fresnelIridescent = EvalIridescence(topIor, savedLdotH, bsdfData.iridescenceThickness, bsdfData.fresnel0);
#endif
F = lerp(F, fresnelIridescent, bsdfData.iridescenceMask);
}
if (HasFeatureFlag(bsdfData.materialFeatures, MATERIALFEATUREFLAGS_STACK_LIT_ANISOTROPY))
{
Stephane Laroche
7 年前