void ApplyDebugToBSDFData(inout BSDFData bsdfData)
{
#ifdef DEBUG_DISPLAY
if (_DebugDisplayMode == DEBUGDISPLAY MODE_SPECULAR_LIGHTING)
if (_DebugLightingMode == DEBUGLIGHTING MODE_SPECULAR_LIGHTING)
{
bool overrideSmoothness = _DebugLightingSmoothness.x != 0.0;
float overrideSmoothnessValue = _DebugLightingSmoothness.y;
}
}
if (_DebugDisplayMode == DEBUGDISPLAY MODE_DIFFUSE_LIGHTING)
if (_DebugLightingMode == DEBUGLIGHTING MODE_DIFFUSE_LIGHTING)
{
bsdfData.diffuseColor = _DebugLightingAlbedo.xyz;
}
void ConfigureTexturingForSSS(inout BSDFData bsdfData)
{
bool performPostScatterTexturing = IsBitSet(_TexturingModeFlags, bsdfData.subsurfaceProfile);
// It's either post-scatter, or pre- and post-scatter texturing.
bsdfData.diffuseColor = performPostScatterTexturing ? float3(1, 1, 1)
: sqrt(bsdfData.diffuseColor);
}
// Evaluates transmittance for a linear combination of two normalized 2D Gaussians.
// Computes results for each color channel separately.
// Ref: Real-Time Realistic Skin Translucency (2010), equation 9 (modified).
return transmittance * tintColor;
}
void FillMaterialIdStandardData(float3 baseColor, float specular, float metallic, float roughness, float3 normalWS, float3 tangentWS, float anisotropy, inout BSDFData bsdfData)
{
bsdfData.diffuseColor = baseColor * (1.0 - metallic);
bsdfData.fresnel0 = lerp(float3(specular.xxx), baseColor, metallic);
// TODO: encode specular
bsdfData.tangentWS = tangentWS;
bsdfData.bitangentWS = cross(normalWS, tangentWS);
ConvertAnisotropyToRoughness(roughness, anisotropy, bsdfData.roughnessT, bsdfData.roughnessB);
bsdfData.anisotropy = anisotropy;
}
void FillMaterialIdSSSData(float3 baseColor, int subsurfaceProfile, float subsurfaceRadius, float thickness, inout BSDFData bsdfData)
{
bsdfData.diffuseColor = baseColor;
// TODO take from subsurfaceProfile
bsdfData.fresnel0 = 0.04; // Should be 0.028 for the skin
bsdfData.subsurfaceProfile = subsurfaceProfile;
// Make the Std. Dev. of 1 correspond to the effective radius of 1 cm (three-sigma rule).
bsdfData.subsurfaceRadius = SSS_UNIT_CONVERSION * subsurfaceRadius + 0.0001;
bsdfData.thickness = SSS_UNIT_CONVERSION * (_ThicknessRemaps[subsurfaceProfile][0] +
_ThicknessRemaps[subsurfaceProfile][1] * thickness);
bsdfData.enableTransmission = IsBitSet(_TransmissionFlags, subsurfaceProfile);
if (bsdfData.enableTransmission)
{
bsdfData.transmittance = ComputeTransmittance( _HalfRcpVariancesAndLerpWeights[subsurfaceProfile][0].xyz,
_HalfRcpVariancesAndLerpWeights[subsurfaceProfile][0].w,
_HalfRcpVariancesAndLerpWeights[subsurfaceProfile][1].xyz,
_HalfRcpVariancesAndLerpWeights[subsurfaceProfile][1].w,
_TintColors[subsurfaceProfile].rgb, bsdfData.thickness, bsdfData.subsurfaceRadius);
}
#ifndef SSS_FILTER_HORIZONTAL_AND_COMBINE // When doing the SSS comine pass, we must not apply the modification of diffuse color
// Handle post-scatter, or pre- and post-scatter texturing.
// We modify diffuseColor here so it affect all the lighting + GI (lightprobe / lightmap) (Need to be done also in GBuffer pass) + transmittance
// diffuseColor will be solely use during lighting pass. The other contribution will be apply in subsurfacescattering convolution.
bool performPostScatterTexturing = IsBitSet(_TexturingModeFlags, subsurfaceProfile);
bsdfData.diffuseColor = performPostScatterTexturing ? float3(1.0, 1.0, 1.0) : sqrt(bsdfData.diffuseColor);
#endif
}
//-----------------------------------------------------------------------------
// conversion function for forward
//-----------------------------------------------------------------------------
if (bsdfData.materialId == MATERIALID_LIT_STANDARD)
{
bsdfData.diffuseColor = surfaceData.baseColor * (1.0 - surfaceData.metallic);
bsdfData.fresnel0 = lerp(float3(surfaceData.specular, surfaceData.specular, surfaceData.specular), surfaceData.baseColor, surfaceData.metallic);
bsdfData.tangentWS = surfaceData.tangentWS;
bsdfData.bitangentWS = cross(surfaceData.normalWS, surfaceData.tangentWS);
ConvertAnisotropyToRoughness(bsdfData.roughness, surfaceData.anisotropy, bsdfData.roughnessT, bsdfData.roughnessB);
bsdfData.anisotropy = surfaceData.anisotropy;
bsdfData.materialId = surfaceData.anisotropy > 0 ? MATERIALID_LIT_ANISO : bsdfData.materialId;
FillMaterialIdStandardData(surfaceData.baseColor, surfaceData.specular, surfaceData.metallic, bsdfData.roughness, surfaceData.normalWS, surfaceData.tangentWS, surfaceData.anisotropy, bsdfData);
bsdfData.materialId = surfaceData.anisotropy > 0.0 ? MATERIALID_LIT_ANISO : bsdfData.materialId;
bsdfData.diffuseColor = surfaceData.baseColor;
// TODO take from subsurfaceProfile
bsdfData.fresnel0 = 0.04; /* 0.028 ? */
bsdfData.subsurfaceProfile = surfaceData.subsurfaceProfile;
// Make the Std. Dev. of 1 correspond to the effective radius of 1 cm (three-sigma rule).
bsdfData.subsurfaceRadius = SSS_UNIT_CONVERSION * surfaceData.subsurfaceRadius + 0.0001;
bsdfData.thickness = SSS_UNIT_CONVERSION * (_ThicknessRemaps[bsdfData.subsurfaceProfile][0] +
_ThicknessRemaps[bsdfData.subsurfaceProfile][1] * surfaceData.thickness);
bsdfData.enableTransmission = IsBitSet(_TransmissionFlags, bsdfData.subsurfaceProfile);
if (bsdfData.enableTransmission)
{
bsdfData.transmittance = ComputeTransmittance(_HalfRcpVariancesAndLerpWeights[bsdfData.subsurfaceProfile][0].xyz,
_HalfRcpVariancesAndLerpWeights[bsdfData.subsurfaceProfile][0].w,
_HalfRcpVariancesAndLerpWeights[bsdfData.subsurfaceProfile][1].xyz,
_HalfRcpVariancesAndLerpWeights[bsdfData.subsurfaceProfile][1].w,
_TintColors[bsdfData.subsurfaceProfile].rgb, bsdfData.thickness, bsdfData.subsurfaceRadius);
}
}
else if (bsdfData.materialId == MATERIALID_LIT_CLEAR_COAT)
{
bsdfData.diffuseColor = surfaceData.baseColor * (1.0 - surfaceData.metallic);
bsdfData.fresnel0 = lerp(float3(surfaceData.specular, surfaceData.specular, surfaceData.specular), surfaceData.baseColor, surfaceData.metallic);
bsdfData.coatNormalWS = surfaceData.coatNormalWS;
bsdfData.coatRoughness = PerceptualSmoothnessToRoughness(surfaceData.coatPerceptualSmoothness);
FillMaterialIdSSSData(surfaceData.baseColor, surfaceData.subsurfaceProfile, surfaceData.subsurfaceRadius, surfaceData.thickness, bsdfData);
}
else if (bsdfData.materialId == MATERIALID_LIT_SPECULAR)
{
#ifdef OUTPUT_SPLIT_LIGHTING
ConfigureTexturingForSSS(bsdfData);
#endif
ApplyDebugToBSDFData(bsdfData);
return bsdfData;
// conversion function for deferred
//-----------------------------------------------------------------------------
#define USE_NORMAL_TETRAHEDRON_ENCODING
#ifdef USE_NORMAL_TETRAHEDRON_ENCODING
// To generate the basisNormal below we use these 4 vertex of a regular tetrahedron
// v0 = float3(1.0, 0.0, -1.0 / sqrt(2.0));
// v1 = float3(-1.0, 0.0, -1.0 / sqrt(2.0));
// v2 = float3(0.0, 1.0, 1.0 / sqrt(2.0));
// v3 = float3(0.0, -1.0, 1.0 / sqrt(2.0));
// Then we normalize the average of each face's vertices
// normalize(v0 + v1 + v2), etc...
static const float3 basisNormal[4] =
{
float3(0., 0.816497, -0.57735),
float3(-0.816497, 0., 0.57735),
float3(0.816497, 0., 0.57735),
float3(0., -0.816497, -0.57735)
};
// Then to get the local matrix (with z axis rotate to basisNormal) use GetLocalFrame(basisNormal[xxx])
static const float3x3 basisArray[4] =
{
float3x3(-1., 0., 0.,0., 0.57735, 0.816497,0., 0.816497, -0.57735),
float3x3(0., -1., 0.,0.57735, 0., 0.816497,-0.816497, 0., 0.57735),
float3x3(0., 1., 0.,-0.57735, 0., 0.816497,0.816497, 0., 0.57735),
float3x3(1., 0., 0.,0., -0.57735, 0.816497,0., -0.816497, -0.57735)
};
// Return [-1..1] vector2 oriented in plane of the faceIndex of a regular tetrahedron
float2 PackNormalTetraEncode(float3 n, out uint faceIndex)
{
// Retrieve the tetrahedra's face for the normal direction
// It is the one with the greatest dot value with face normal
float dot0 = dot(n, basisNormal[0]);
float dot1 = dot(n, basisNormal[1]);
float dot2 = dot(n, basisNormal[2]);
float dot3 = dot(n, basisNormal[3]);
float maxi0 = max(dot0, dot1);
float maxi1 = max(dot2, dot3);
float maxi = max(maxi0, maxi1);
// Get the index from the greatest dot
if (maxi == dot0)
faceIndex = 0;
else if (maxi == dot1)
faceIndex = 1;
else if (maxi == dot2)
faceIndex = 2;
else //(maxi == dot3)
faceIndex = 3;
// Rotate n into this local basis
n = mul(basisArray[faceIndex], n);
// Project n onto the local plane
return n.xy;
}
// Assume f [-1..1]
float3 UnpackNormalTetraEncode(float2 f, uint faceIndex)
{
// Recover n from local plane
float3 n = float3(f.xy, sqrt(1.0 - dot(f.xy, f.xy)));
// Inverse of transform PackNormalTetraEncode (just swap order in mul as we have a rotation)
return mul(n, basisArray[faceIndex]);
}
#endif
// Encode SurfaceData (BSDF parameters) into GBuffer
// Must be in sync with RT declared in HDRenderPipeline.cs ::Rebuild
void EncodeIntoGBuffer( SurfaceData surfaceData,
outGBuffer0 = float4(surfaceData.baseColor, surfaceData.specularOcclusion);
// RT1 - 10:10:10:2
// We store perceptualRoughness instead of roughness because it save a sqrt ALU when decoding
// (as we want both perceptualRoughness and roughness for the lighting due to Disney Diffuse model)
#ifdef USE_NORMAL_TETRAHEDRON_ENCODING
// Encode normal on 20bit + 2bit (faceIndex) with tetrahedal compression
uint faceIndex;
float2 tetraNormalWS = PackNormalTetraEncode(surfaceData.normalWS, faceIndex);
// Store faceIndex on two bits with perceptualRoughness
outGBuffer1 = float4(tetraNormalWS * 0.5 + 0.5, PackFloatInt10bit(PerceptualSmoothnessToPerceptualRoughness(surfaceData.perceptualSmoothness), faceIndex, 4.0), PackMaterialId(surfaceData.materialId));
#else
// We store perceptualRoughness instead of roughness because it save a sqrt ALU when decoding
// (as we want both perceptualRoughness and roughness for the lighting due to Disney Diffuse model)
// TODO: Store 2 bit of flag into perceptualSmoothness (one for SSR, other is free (deferred planar reflection ID ? / MatID extension ?)
#endif
// RT2 - 8:8:8:8
if (surfaceData.materialId == MATERIALID_LIT_STANDARD)
else if (surfaceData.materialId == MATERIALID_LIT_SSS)
{
outGBuffer2 = float4(surfaceData.subsurfaceRadius, surfaceData.thickness, 0.0, surfaceData.subsurfaceProfile * rcp(SSS_N_PROFILES - 1));
}
else if (surfaceData.materialId == MATERIALID_LIT_CLEAR_COAT)
{
// Encode coat normal on 16bit with oct compression
float2 octCoatNormalWS = PackNormalOctEncode(surfaceData.coatNormalWS);
// TODO: store metal and specular together, specular should be an enum (fixed value)
outGBuffer2 = float4(octCoatNormalWS * 0.5 + 0.5, PerceptualSmoothnessToRoughness(surfaceData.coatPerceptualSmoothness), surfaceData.metallic);
}
else if (surfaceData.materialId == MATERIALID_LIT_SPECULAR)
{
float3 baseColor = inGBuffer0.rgb;
bsdfData.specularOcclusion = inGBuffer0.a;
#ifdef USE_NORMAL_TETRAHEDRON_ENCODING
uint faceIndex;
UnpackFloatInt10bit(inGBuffer1.b, 4.0, bsdfData.perceptualRoughness, faceIndex);
bsdfData.normalWS = UnpackNormalTetraEncode(inGBuffer1.xy * 2.0 - 1.0, faceIndex);
#else
#endif
int supportsClearCoat = (featureFlags & (MATERIALID_LIT_CLEAR_COAT)) != 0;
if(supportsStandard + supportsSSS + supportsClearCoat + supportsSpecular > 1)
if(supportsStandard + supportsSSS + supportsSpecular > 1)
{
bsdfData.materialId = UnpackMaterialId(inGBuffer1.a); // only fetch materialid if it is not statically known from feature flags
}
if(supportsStandard) bsdfData.materialId = MATERIALID_LIT_STANDARD;
else if(supportsSSS) bsdfData.materialId = MATERIALID_LIT_SSS;
else if(supportsClearCoat) bsdfData.materialId = MATERIALID_LIT_CLEAR_COAT;
else bsdfData.materialId = MATERIALID_LIT_SPECULAR;
}
// TODO extract spec
float specular = 0.04;
float specular = 0.04; // TODO extract spec
bsdfData.diffuseColor = baseColor * (1.0 - metallic);
bsdfData.fresnel0 = lerp(float3(specular, specular, specular), baseColor, metallic);
bsdfData.tangentWS = UnpackNormalOctEncode(float2(inGBuffer2.rg * 2.0 - 1.0));
bsdfData.bitangentWS = cross(bsdfData.normalWS, bsdfData.tangentWS);
ConvertAnisotropyToRoughness(bsdfData.roughness, anisotropy, bsdfData.roughnessT, bsdfData.roughnessB);
bsdfData.anisotropy = anisotropy;
float3 tangentWS = UnpackNormalOctEncode(float2(inGBuffer2.rg * 2.0 - 1.0));
FillMaterialIdStandardData(baseColor, specular, metallic, bsdfData.roughness, bsdfData.normalWS, tangentWS, anisotropy, bsdfData);
if ((featureFlags & FEATURE_FLAG_MATERIAL_LIT_ANISO) && (featureFlags & FEATURE_FLAG_MATERIAL_LIT_STANDARD) == 0 || anisotropy > 0)
{
else if (supportsSSS && bsdfData.materialId == MATERIALID_LIT_SSS)
{
bsdfData.diffuseColor = baseColor;
// TODO take from subsurfaceProfile
bsdfData.fresnel0 = 0.04; /* 0.028 ? */
bsdfData.subsurfaceProfile = (SSS_N_PROFILES - 0.9) * inGBuffer2.a; // Need to bias for integers to round trip through the G-buffer
// Make the Std. Dev. of 1 correspond to the effective radius of 1 cm (three-sigma rule).
bsdfData.subsurfaceRadius = SSS_UNIT_CONVERSION * inGBuffer2.r + 0.0001;
bsdfData.thickness = SSS_UNIT_CONVERSION * (_ThicknessRemaps[bsdfData.subsurfaceProfile][0] +
_ThicknessRemaps[bsdfData.subsurfaceProfile][1] * inGBuffer2.g);
bsdfData.enableTransmission = IsBitSet(_TransmissionFlags, bsdfData.subsurfaceProfile);
if (bsdfData.enableTransmission)
{
bsdfData.transmittance = ComputeTransmittance(_HalfRcpVariancesAndLerpWeights[bsdfData.subsurfaceProfile][0].xyz,
_HalfRcpVariancesAndLerpWeights[bsdfData.subsurfaceProfile][0].w,
_HalfRcpVariancesAndLerpWeights[bsdfData.subsurfaceProfile][1].xyz,
_HalfRcpVariancesAndLerpWeights[bsdfData.subsurfaceProfile][1].w,
_TintColors[bsdfData.subsurfaceProfile].rgb, bsdfData.thickness, bsdfData.subsurfaceRadius);
}
}
else if (supportsClearCoat && bsdfData.materialId == MATERIALID_LIT_CLEAR_COAT)
{
float metallic = inGBuffer2.a;
// TODO extract spec
float specular = 0.04;
bsdfData.diffuseColor = baseColor * (1.0 - metallic);
bsdfData.fresnel0 = lerp(float3(specular, specular, specular), baseColor, metallic);
bsdfData.coatNormalWS = UnpackNormalOctEncode(float2(inGBuffer2.rg * 2.0 - 1.0));
bsdfData.coatRoughness = inGBuffer2.b;
int subsurfaceProfile = (SSS_N_PROFILES - 0.9) * inGBuffer2.a;
float subsurfaceRadius = inGBuffer2.r;
float thickness = inGBuffer2.g;
FillMaterialIdSSSData(baseColor, subsurfaceProfile, subsurfaceRadius, thickness, bsdfData);
}
else if (supportsSpecular && bsdfData.materialId == MATERIALID_LIT_SPECULAR)
{
bakeDiffuseLighting = inGBuffer3.rgb;
#ifdef OUTPUT_SPLIT_LIGHTING
ConfigureTexturingForSSS(bsdfData);
#endif
ApplyDebugToBSDFData(bsdfData);
}
{
featureFlags |= FEATURE_FLAG_MATERIAL_LIT_SSS;
}
else if (materialId == MATERIALID_LIT_CLEAR_COAT)
{
featureFlags |= FEATURE_FLAG_MATERIAL_LIT_CLEAR_COAT;
}
else if (materialId == MATERIALID_LIT_SPECULAR)
{
featureFlags |= FEATURE_FLAG_MATERIAL_LIT_SPECULAR;
// Precomputed lighting data to send to the various lighting functions
struct PreLightData
{
// General
// GGX iso
// Aniso
// GGX Aniso
// IBL
float3 iblDirWS; // Dominant specular direction, used for IBL in EvaluateBSDF_Env()
float iblMipLevel;
{
PreLightData preLightData;
// We have handle the case of NdotV being negative in GetData() function with GetShiftedNdotV.
// So we don't need to saturate or take the abs here.
// In case a material use negative normal for double sided lighting like speedtree this will be handle in the GetData() code too.
preLightData.NdotV = dot(bsdfData.normalWS, V);
// General
float3 iblNormalWS = bsdfData.normalWS;
// GetShiftedNdotV return a positive NdotV
// In case a material use negative normal for double sided lighting like Speedtree they need to do a new calculation
preLightData.NdotV = GetShiftedNdotV(iblNormalWS, V); // Handle artificat for specular lighting
// GGX iso
float iblNdotV = preLightData.NdotV;
float3 iblNormalWS = bsdfData.normalWS;
// Check if we precompute anisotropy too
// GGX aniso
if (bsdfData.materialId == MATERIALID_LIT_ANISO)
{
preLightData.TdotV = dot(bsdfData.tangentWS, V);
iblNormalWS = GetAnisotropicModifiedNormal(bsdfData.bitangentWS, bsdfData.normalWS, V, bsdfData.anisotropy);
iblNormalWS = GetAnisotropicModifiedNormal(bsdfData.bitangentWS, iblNormalWS, V, bsdfData.anisotropy);
// NOTE: If we follow the theory we should use the modified normal for the different calculation implying a normal (like NDotV) and use iblNormalWS
// NOTE: If we follow the theory we should use the modified normal for the different calculation implying a normal (like NdotV) and use iblNormalWS
GetPreIntegratedFGD(iblNdotV, bsdfData.perceptualRoughness, bsdfData.fresnel0, preLightData.specularFGD, preLightData.diffuseFGD);
// IBL
GetPreIntegratedFGD(preLightData.NdotV, bsdfData.perceptualRoughness, bsdfData.fresnel0, preLightData.specularFGD, preLightData.diffuseFGD);
// Area light specific
// Area light
// UVs for sampling the LUTs
float theta = FastACos(preLightData.NdotV);
float2 uv = LTC_LUT_OFFSET + LTC_LUT_SCALE * float2(bsdfData.perceptualRoughness, theta * INV_HALF_PI);
float NdotL = saturate(dot(bsdfData.normalWS, L));
float NdotV = preLightData.NdotV;
float LdotV = dot(L, V);
float invLenLV = rsqrt(abs(2 + 2 * LdotV)); // invLenLV = rcp(length(L + V))
// GCN Optimization: reference PBR Diffuse Lighting for GGX + Smith Microsurfaces
float invLenLV = rsqrt(abs(2.0 * LdotV + 2.0)); // invLenLV = rcp(length(L + V))
float LdotH = saturate(invLenLV + invLenLV * LdotV);
float LdotH = saturate(invLenLV * LdotV + invLenLV);
float3 F = F_Schlick(bsdfData.fresnel0, LdotH);
[branch] if (bsdfData.enableTransmission)
{
// Reverse the normal.
illuminance = saturate(dot(-bsdfData.normalWS, L));
// Reverse the normal + do some wrap lighting to have a nicer transition between regular lighting and transmittance
// Ref: Steve McAuley - Energy-Conserving Wrapped Diffuse
const float w = 0.15;
float illuminance = saturate((dot(-bsdfData.normalWS, L) + w) / ((1.0 + w) * (1.0 + w)));
// For low thickness, we can reuse the shadowing status for the back of the object.
shadow = (bsdfData.thickness <= SSS_LOW_THICKNESS) ? shadow : 1;
illuminance *= shadow * cookie.a;
[branch] if (bsdfData.enableTransmission)
{
// Reverse the normal.
illuminance = saturate(dot(-bsdfData.normalWS, L)) * attenuation;
// Reverse the normal + do some wrap lighting to have a nicer transition between regular lighting and transmittance
// Ref: Steve McAuley - Energy-Conserving Wrapped Diffuse
const float w = 0.15;
float illuminance = saturate((dot(-bsdfData.normalWS, L) + w) / ((1.0 + w) * (1.0 + w)));
illuminance *= attenuation;
// For low thickness, we can reuse the shadowing status for the back of the object.
shadow = (bsdfData.thickness <= SSS_LOW_THICKNESS) ? shadow : 1;
illuminance *= shadow * cookie.a;
[branch] if (bsdfData.enableTransmission)
{
// Reverse the normal.
illuminance = saturate(dot(-bsdfData.normalWS, L) * clipFactor);
// Reverse the normal + do some wrap lighting to have a nicer transition between regular lighting and transmittance
// Ref: Steve McAuley - Energy-Conserving Wrapped Diffuse
const float w = 0.15;
float illuminance = saturate((dot(-bsdfData.normalWS, L) + w) / ((1.0 + w) * (1.0 + w)));
illuminance *= clipFactor;
// For low thickness, we can reuse the shadowing status for the back of the object.
shadow = (bsdfData.thickness <= SSS_LOW_THICKNESS) ? shadow : 1;
illuminance *= shadow * cookie.a;