// Vlayer config options:
#ifdef _VLAYERED_RECOMPUTE_PERLIGHT
# define VLAYERED_RECOMPUTE_PERLIGHT
#define VLAYERED_RECOMPUTE_PERLIGHT
//#define VLAYERED_USE_REFRACTED_ANGLES_FOR_BASE
#ifdef _VLAYERED_USE_REFRACTED_ANGLES_FOR_BASE
#define VLAYERED_USE_REFRACTED_ANGLES_FOR_BASE
#endif
#define VLAYERED_DIFFUSE_ENERGY_HACKED_TERM
//#define VLAYERED_ANISOTROPY_IBL_DESTRETCH
# define NB_NORMALS 1
#endif
#if defined(VLAYERED_USE_REFRACTED_ANGLES_FOR_BASE)
# define NB_LV_DIR 2 // NB of interfaces with different L or V directions to consider (see BSDF( ) )
#else
# define NB_LV_DIR 1
#endif
#else // _MATERIAL_FEATURE_COAT
#else // ! _MATERIAL_FEATURE_COAT
# undef VLAYERED_USE_REFRACTED_ANGLES_FOR_BASE
# undef _MATERIAL_FEATURE_COAT_NORMALMAP // enforce a "coat enabled subfeature" condition on this shader_feature
# define COAT_NB_LOBES 0
# define NB_NORMALS 1
# define NB_LV_DIR 1
# define IF_FEATURE_COAT(a)
#define COAT_NORMAL_IDX 0
#define BASE_NORMAL_IDX (NB_NORMALS-1)
// For NB_LV_DIR arrays: make sure these indices match the above
#define TOP_DIR_IDX 0
#define BOTTOM_DIR_IDX (NB_LV_DIR-1)
// TODO: if dual lobe base
//#define BASE_NB_LOBES 1
// GetPreLightData prototype.
//-----------------------------------------------------------------------------
// Precomputed lighting data to send to the various lighting functions
struct PreLightData
{
// using the geometric normal, we will reconstruct a direction for the bottom
// interface using the "V and geomNormalWS" plane as a plane of incidence. So we
// calculate a pseudo-refracted angle in this plane, and with an orthogonal basis
// of it (using the orthogonal complement of V vs geomNormalWS), we will reconstruct
// of it (2D basis embedded in 3D, ie basis formed by two 3D vectors)
// (using the orthogonal complement of V vs geomNormalWS), we will reconstruct
// the "V at the bottom interface". This V will then in turn be usable for further
// FGD / Fresnel calculations with the bottom interface normal (from the bottom
// normal map), which is not necessarily coplanar with V and geomNormalWS, hence
// At this point cti should be properly (coatNormalWS dot V) or NdotV or VdotH, see ComputeAdding.
// In the special case where we do have a coat normal, we will propagate a different angle than
// (coatNormalWS dot V) and vOrthoGeomN will be used.
// vOrthoGeomN is the orthogonal complement of V wrt geomNormalWS.
if (useGeomN)
{
cti = ClampNdotV(dot(bsdfData.geomNormalWS, V));
// _cti should be (coatNormalWS dot V) if calledPerLight == false and we have a coat normal map. V is used in this case
#ifdef VLAYERED_DEBUG
if( _DebugLobeMask.w == 0.0)
if( _DebugEnv LobeMask.w == 0.0)
{
preLightData.vLayerEnergyCoeff[COAT_LOBE_IDX] = 0.0 * F_Schlick(IorToFresnel0(bsdfData.coatIor), _cti);
preLightData.iblPerceptualRoughness[COAT_LOBE_IDX] = bsdfData.coatPerceptualRoughness;
// Then we need anisotropic roughness updates again for the 2
// bottom lobes, for analytical lights.
//
// TODO: VLAYERED_RECOMPUTE_PERLIGHT and calledPerLight bool
// First, to be less messy, immediately transfer vLayerPerceptualRoughness
// data into the iblPerceptualRoughness[] array
float baseLayerNdotV;
if ( IsCoatNormalMapEnabled(bsdfData) )
{
//slnote
baseLayerNdotV = preLightData.bottomAngleFGD;
}
else
float3 N[NB_NORMALS];
float NdotV[NB_NORMALS];
// slnote dual map
PreLightData_SetupNormals(bsdfData, preLightData, V, N, NdotV);
preLightData.diffuseEnergy = float3(1.0, 1.0, 1.0);
float3 iblR[TOTAL_NB_LOBES];
float specularReflectivity[TOTAL_NB_LOBES];
float diffuseFGD[BASE_NB_LOBES];
//float baseLayerNdotV = NdotV; slnote
if( IsVLayeredEnabled(bsdfData) )
{
stretch[1] = abs(preLightData.iblAnisotropy[1]) * saturate(5 * preLightData.iblPerceptualRoughness[BASE_LOBEB_IDX]);
iblN[COAT_LOBE_IDX] = N[COAT_NORMAL_IDX]; // no anisotropy for coat.
iblN[BASE_LOBEA_IDX] = GetAnisotropicModifiedNormal(grainDirWS[0], N[BASE_NORMAL_IDX], V, stretch[0]); // slnote dual map
iblN[BASE_LOBEA_IDX] = GetAnisotropicModifiedNormal(grainDirWS[0], N[BASE_NORMAL_IDX], V, stretch[0]);
iblN[BASE_LOBEB_IDX] = GetAnisotropicModifiedNormal(grainDirWS[1], N[BASE_NORMAL_IDX], V, stretch[1]);
}
preLightData.partLambdaV[BASE_LOBEB_IDX] = GetSmithJointGGXPartLambdaV(NdotV[BASE_NORMAL_IDX], preLightData.layeredRoughnessT[1]);
#endif
iblN[COAT_LOBE_IDX] = N[COAT_NORMAL_IDX];
iblN[BASE_LOBEA_IDX] = iblN[BASE_LOBEB_IDX] = N[BASE_NORMAL_IDX]; // slnote dual map
iblN[BASE_LOBEA_IDX] = iblN[BASE_LOBEB_IDX] = N[BASE_NORMAL_IDX];
} // anisotropy
// IBL
// because our ComputeAdding formulation is with "energy" coefficients calculated with a
// chain of Fresnel terms instead of a correct chain computed with the true FGD.
// slnote dual map: get base layer angle: could store it always from computeadding
//float baseLayerNdotV = sqrt(1 + Sq(preLightData.coatIeta)*(Sq(NdotV) - 1));
//TODO refactor with EvalIridescence, Lit::GetPreLightData
float baseLayerNdotV = PreLightData_GetBaseNdotVForFGD(bsdfData, preLightData, NdotV);
// BSDF share between directional light, punctual light and area light (reference)
//-----------------------------------------------------------------------------
// helpers
// BSDF helpers
void BSDF_SetupNormals(BSDFData bsdfData, float3 L, out float3 N[NB_NORMALS], out float NdotL[NB_NORMALS])
{
N[BASE_NORMAL_IDX] = bsdfData.normalWS;
NdotL[BASE_NORMAL_IDX] = dot(N[BASE_NORMAL_IDX], L);
//
// The following is to streamline the usage (in the BSDF evaluations) of NdotL[] and NdotV[]
// regardless of the reason why we need [2] sized arrays:
//
#if defined(VLAYERED_USE_REFRACTED_ANGLES_FOR_BASE) || defined(_MATERIAL_FEATURE_COAT_NORMALMAP)
#define DNLV_COAT_IDX 0
#define DNLV_BASE_IDX 1
#else
#define DNLV_COAT_IDX 0
#define DNLV_BASE_IDX 0
#endif
#if ((DNLV_BASE_IDX != BASE_NORMAL_IDX) && (DNLV_BASE_IDX != BOTTOM_DIR_IDX)) || ((DNLV_COAT_IDX != COAT_NORMAL_IDX) && (DNLV_BASE_IDX != COAT_DIR_IDX))
#error "DIR and NORMAL indices should match"
#endif
#ifdef _MATERIAL_FEATURE_COAT_NORMALMAP
if ( IsCoatNormalMapEnabled(bsdfData) )
{
N[COAT_NORMAL_IDX] = bsdfData.coatNormalWS;
NdotL[COAT_NORMAL_IDX] = dot(N[COAT_NORMAL_IDX], L);
}
#if defined(VLAYERED_USE_REFRACTED_ANGLES_FOR_BASE)
// static assert:
#if defined(_MATERIAL_FEATURE_COAT_NORMALMAP) && ((NB_LV_DIR != 2) || ( NB_NORMALS != 2) || (BASE_NORMAL_IDX != BOTTOM_DIR_IDX) || (COAT_NORMAL_IDX != TOP_DIR_IDX))
#error "Unexpected NB_NORMALS and/or NB_LV_DIR, should be 2 or unmatching indices between DIR_IDX vs NORMAL_IDX"
}
#define NDOTLV_SIZE NB_LV_DIR
#else
#define NDOTLV_SIZE NB_NORMALS
#endif //...defined(VLAYERED_USE_REFRACTED_ANGLES_FOR_BASE)
void CalculateAnisoAngles(BSDFData bsdfData, float3 L, float3 V, float invLenLV, out float TdotH, out float TdotL, out float BdotH, out float BdotL)
{
float3 H = (L + V) * invLenLV;
// For anisotropy we must not saturate these values
TdotH = dot(bsdfData.tangentWS, H);
TdotL = dot(bsdfData.tangentWS, L);
BdotH = dot(bsdfData.bitangentWS, H);
BdotL = dot(bsdfData.bitangentWS, L);
}
void CalculateAngles(BSDFData bsdfData, float3 L, float3 V, float NdotL[NB_NORMALS], float unclampedNdotV[NB_NORMALS],
out float LdotV, out float invLenLV, out float NdotH[NB_NORMALS], out float LdotH, out float NdotV[NB_NORMALS])
{
// Optimized math. Ref: PBR Diffuse Lighting for GGX + Smith Microsurfaces (slide 114).
LdotV = dot(L, V);
invLenLV = rsqrt(max(2.0 * LdotV + 2.0, FLT_EPS)); // invLenLV = rcp(length(L + V)), clamp to avoid rsqrt(0) = NaN
LdotH = saturate(invLenLV * LdotV + invLenLV);
//BSDF_SetupNormalsAndAngles(bsdfData, preLightData, inNdotL,
// L, V, N, NdotL,
// H, NdotH, savedLdotH, NdotV);
NdotH[BASE_NORMAL_IDX] = saturate((NdotL[BASE_NORMAL_IDX] + unclampedNdotV[BASE_NORMAL_IDX]) * invLenLV); // Do not clamp NdotV here
NdotV[BASE_NORMAL_IDX] = ClampNdotV(unclampedNdotV[BASE_NORMAL_IDX]);
void BSDF_SetupNormalsAndAngles(BSDFData bsdfData, inout PreLightData preLightData, float inNdotL,
inout float3 L[NB_LV_DIR], inout float3 V[NB_LV_DIR], out float3 N[NB_NORMALS], out float NdotL[NDOTLV_SIZE],
out float3 H, out float NdotH[NB_NORMALS], out float savedLdotH, out float NdotV[NDOTLV_SIZE])
{
H = float3(0.0, 0.0, 0.0);
N[BASE_NORMAL_IDX] = bsdfData.normalWS;
#ifdef _MATERIAL_FEATURE_COAT_NORMALMAP
#if defined(_MATERIAL_FEATURE_COAT_NORMALMAP)
NdotH[COAT_NORMAL_IDX] = saturate((NdotL[COAT_NORMAL_IDX] + unclampedNdotV[COAT_NORMAL_IDX]) * invLenLV); // Do not clamp NdotV here
NdotV[COAT_NORMAL_IDX] = ClampNdotV(unclampedNdotV[COAT_NORMAL_IDX]);
N[COAT_NORMAL_IDX] = bsdfData.coatNormalWS;
}
// This function apply BSDF. Assumes that NdotL is positive.
void BSDF( float3 V, float3 L, float inNdotL, float3 positionWS, PreLightData preLightData, BSDFData bsdfData,
out float3 diffuseLighting,
out float3 specularLighting)
{
//float3 N = bsdfData.normalWS; // slnote : dual normal maps
float3 N[NB_NORMALS];
float NdotL[NB_NORMALS];
BSDF_SetupNormals(bsdfData, L, N, NdotL);
// preLightData.NdotV is sized with NB_NORMALS, not NDOTLV_SIZE, because the only useful
// precalculation that is not per light is NdotV with the coat normal (if it exists) and
// NdotV with the base normal (if coat normal exists), with the same V.
// But if VLAYERED_USE_REFRACTED_ANGLES_FOR_BASE is used, V is different at the bottom,
// and we will recalculate a refracted (along H) V here, per light, and the resulting base
// NdotV.
float unclampedNdotV[NB_NORMALS] = preLightData.NdotV;
float LdotV, invLenLV, NdotH[NB_NORMALS], LdotH, NdotV[NB_NORMALS];
// Optimized math. Ref: PBR Diffuse Lighting for GGX + Smith Microsurfaces (slide 114).
//float LdotV = dot(L, V);
//float invLenLV = rsqrt(max(2.0 * LdotV + 2.0, FLT_EPS)); // invLenLV = rcp(length(L + V)), clamp to avoid rsqrt(0) = NaN
//float NdotH = saturate((NdotL + preLightData.NdotV) * invLenLV); // Do not clamp NdotV here
//float LdotH = saturate(invLenLV * LdotV + invLenLV);
//float NdotV = ClampNdotV(preLightData.NdotV);
CalculateAngles(bsdfData, L, V, NdotL, preLightData.NdotV, LdotV, invLenLV, NdotH, LdotH, NdotV);
// static assert (to simplify code, COAT_NORMAL_IDX == BASE_NORMAL_IDX when no coat normal):
#if !defined(_MATERIAL_FEATURE_COAT_NORMALMAP) && (BASE_NORMAL_IDX != COAT_NORMAL_IDX)
#error "COAT_NORMAL_IDX shoud equal BASE_NORMAL_IDX when no coat normal map"
#endif
float3 DV[TOTAL_NB_LOBES];
// We will compute everything needed for top interface lighting, and this will alias to the
// (only) bottom interface when we're not vlayered (if we are and have a coat normal, we will
// use it as we transfered coatNormalWS above and if we don't, again, the only existing
// normal will be used)
// TODO: Proper Fresnel
float3 F = F_Schlick(bsdfData.fresnel0, LdotH);
// todo: inNdotL is with geometric N for now, so we don't use it.
NdotL[DNLV_COAT_IDX] = dot(N[COAT_NORMAL_IDX], L[TOP_DIR_IDX]);
// TODO: with iridescence, will be optionally per light sample
// Optimized math. Ref: PBR Diffuse Lighting for GGX + Smith Microsurfaces (slide 114).
float LdotV = dot(L[TOP_DIR_IDX], V[TOP_DIR_IDX]); // note: LdotV isn't reused elsewhere, just here.
float invLenLV = rsqrt(max(2.0 * LdotV + 2.0, FLT_EPS)); // invLenLV = rcp(length(L + V)), clamp to avoid rsqrt(0) = NaN
savedLdotH = saturate(invLenLV * LdotV + invLenLV);
NdotH[COAT_NORMAL_IDX] = saturate((NdotL[DNLV_COAT_IDX] + unclampedNdotV[COAT_NORMAL_IDX]) * invLenLV); // Do not clamp NdotV here
NdotV[DNLV_COAT_IDX] = ClampNdotV(unclampedNdotV[COAT_NORMAL_IDX]);
// --------------------------------------------------------------------
// VLAYERING:
// --------------------------------------------------------------------
// Save top angles in case VLAYERED_USE_REFRACTED_ANGLES_FOR_BASE option is used
float topLdotH = LdotH; // == VdotH)
float topNdotH = NdotH[COAT_NORMAL_IDX];
float topNdotL = NdotL[COAT_NORMAL_IDX];
float topNdotV = NdotV[COAT_NORMAL_IDX];
// NdotH[] is size 2 only if we have two normal maps, but it doesn't change if we refract along
// H itself, so refracted angles considerations don't matter for it. Still we need to calculate
// it if we have two normal maps. Note we don't even test _MATERIAL_FEATURE_COAT_NORMALMAP, as
// BASE_NORMAL_IDX should alias COAT_NORMAL_IDX if there's no coat normalmap, and this line
// becomes a nop.
// We still reuse the top directions to be able to reuse computations above, regardless of
// refracted angle option since NdotH is invariant to it.
NdotH[BASE_NORMAL_IDX] = saturate((dot(N[BASE_NORMAL_IDX], L[TOP_DIR_IDX]) + unclampedNdotV[BASE_NORMAL_IDX]) * invLenLV); // Do not clamp NdotV here
#if defined(VLAYERED_USE_REFRACTED_ANGLES_FOR_BASE) || defined(_MATERIAL_FEATURE_ANISOTROPY)
// In both of these cases, we need H, so get this out of the way now:
H = (L[TOP_DIR_IDX] + V[TOP_DIR_IDX]) * invLenLV; // H stays the same so calculate it one time
#endif
#ifdef VLAYERED_RECOMPUTE_PERLIGHT
// TODOWIP
// Must call ComputeAdding and update partLambdaV
ComputeAdding(savedLdotH, V[TOP_DIR_IDX], bsdfData, preLightData, true);
// Notice the top LdotH as interface angle, symmetric model parametrization (see paper sec. 6 and comments
// on ComputeAdding)
// layered*Roughness* and vLayerEnergyCoeff are now updated for the proper light direction.
// !Updates to PartLambdaV are now needed, will be done later when we consider anisotropy.
// Note (see p9 eq(39)): if we don't recompute per light, we just reuse the IBL energy terms as the fresnel
// terms for our LdotH, too bad (similar to what we do with iridescence), along with the "wrongly" calculated
// energy.
// In any case, we should have used FGD terms (except for R12 at the start of the process) for the analytical
// light case, see comments at the top of ComputeAdding
#endif //...VLAYERED_RECOMPUTE_PERLIGHT
// Also, we will use the base normal map automatically if we have dual normal maps (coat normals)
// since we use generically N[BASE_NORMAL_IDX]
// TODO: not done with dual normal maps
// Use the refracted angle at the bottom interface for BSDF calculations:
// Seems like the more correct ones to use, but not obvious as we have the energy
// and moreover, currently, the output coefficients of the method are formed from straight
// Fresnel terms, and not FGD terms.
//
float3 H = (L + V) * invLenLV;
// H stays the same so calculate it one time
V = CoatRefract(V, H, preLightData.coatIeta);
L = reflect(-V, H);
NdotL = dot(N,L); // slnote : dual normal maps
V[BOTTOM_DIR_IDX] = CoatRefract(V[TOP_DIR_IDX], H, preLightData.coatIeta);
L[BOTTOM_DIR_IDX] = reflect(-V[BOTTOM_DIR_IDX], H);
NdotL[DNLV_BASE_IDX] = dot(N[BASE_NORMAL_IDX], L[BOTTOM_DIR_IDX]);
//LdotV = dot(L, V);
//invLenLV = rsqrt(max(2.0 * LdotV + 2.0, FLT_EPS)); // invLenLV = rcp(length(L + V)), clamp to avoid rsqrt(0) = NaN
//NdotH = saturate((NdotL + dot(N, V)) * invLenLV); // Do not clamp NdotV here
//LdotH = saturate(invLenLV * LdotV + invLenLV);
//NdotV = ClampNdotV(dot(N, V));
CalculateAngles(L, V, NdotL, dot(N, V), LdotV, invLenLV, NdotH, LdotH, NdotV); // slnote : dual normal maps
float unclampedBaseNdotV = dot(N[BASE_NORMAL_IDX], V[BOTTOM_DIR_IDX]);
NdotV[DNLV_BASE_IDX] = ClampNdotV(unclampedBaseNdotV);
#endif // #ifdef VLAYERED_USE_REFRACTED_ANGLES_FOR_BASE
//NdotH[BASE_NORMAL_IDX] = already calculated, see above
#ifdef VLAYERED_RECOMPUTE_PERLIGHT
// TODOWIP
// Must call ComputeAdding and update partLambdaV
ComputeAdding(topLdotH, V, bsdfData, preLightData, true);
//slnote dual maps
//ComputeAdding(NdotV[COAT_NORMAL_IDX], V, bsdfData, preLightData, false);
// Notice topLdotH as interface angle, symmetric model parametrization (see paper sec. 6 and comments
// on ComputeAdding)
// layered*Roughness* and vLayerEnergyCoeff are now updated for the proper light direction.
preLightData.partLambdaV[COAT_LOBE_IDX] = GetSmithJointGGXPartLambdaV(topNdotV, preLightData.layeredCoatRoughness);
#else //, don't use refracted angles for bottom interface:
#if defined(_MATERIAL_FEATURE_COAT_NORMALMAP)
if ( IsCoatNormalMapEnabled(bsdfData) )
{
// Just to be clean we test the above, but since BASE_NORMAL_IDX should alias COAT_NORMAL_IDX
// if we don't have coat normals and no refracted angle to account, this is already computed
// and the compiler would remove this.
NdotL[DNLV_BASE_IDX] = dot(N[BASE_NORMAL_IDX], L[BOTTOM_DIR_IDX]);
//NdotH[BASE_NORMAL_IDX] = saturate((NdotL[DNLV_BASE_IDX] + unclampedNdotV[BASE_NORMAL_IDX]) * invLenLV); // Do not clamp NdotV here
NdotV[DNLV_BASE_IDX] = ClampNdotV(unclampedNdotV[BASE_NORMAL_IDX]);
}
// p9 eq(39): if we don't recompute per light, we just reuse the IBL energy terms as the fresnel terms
// for our LdotH, too bad (similar to what we do with iridescence), along with the "wrongly" calculated energy.
// Note that in any case, we should have used FGD terms (except for R12 at the start of the process)
// for the analytical light case, see comments at the top of ComputeAdding
#endif // #ifdef VLAYERED_USE_REFRACTED_ANGLES_FOR_BASE
// Finally, we will update the partLambdaV if we did ComputeAdding per light, having the proper
// angles wrt to refraction option and/or dual normal maps and considering anisotropy:
// we just changed V, update those:
preLightData.TdotV = dot(bsdfData.tangentWS, V);
preLightData.BdotV = dot(bsdfData.bitangentWS, V);
// we changed V, update those:
preLightData.TdotV = dot(bsdfData.tangentWS, V[BOTTOM_DIR_IDX]);
preLightData.BdotV = dot(bsdfData.bitangentWS, V[BOTTOM_DIR_IDX]);
preLightData.partLambdaV[BASE_LOBEA_IDX] = GetSmithJointGGXAnisoPartLambdaV(preLightData.TdotV, preLightData.BdotV, NdotV[BASE_NORMAL_IDX],
// we need to update partLambdaV as we recomputed the layering for this light (these depend on roughness):
preLightData.partLambdaV[COAT_LOBE_IDX] = GetSmithJointGGXPartLambdaV(NdotV[DNLV_COAT_IDX], preLightData.layeredCoatRoughness);
preLightData.partLambdaV[BASE_LOBEA_IDX] = GetSmithJointGGXAnisoPartLambdaV(preLightData.TdotV, preLightData.BdotV, NdotV[DNLV_BASE_IDX],
preLightData.partLambdaV[BASE_LOBEB_IDX] = GetSmithJointGGXAnisoPartLambdaV(preLightData.TdotV, preLightData.BdotV, NdotV[BASE_NORMAL_IDX],
preLightData.partLambdaV[BASE_LOBEB_IDX] = GetSmithJointGGXAnisoPartLambdaV(preLightData.TdotV, preLightData.BdotV, NdotV[DNLV_BASE_IDX],
} // anisotropy
else
{
#ifdef VLAYERED_RECOMPUTE_PERLIGHT
// we need to update partLambdaV as we recomputed the layering for this light (these depend on roughness):
preLightData.partLambdaV[COAT_LOBE_IDX] = GetSmithJointGGXPartLambdaV(NdotV[DNLV_COAT_IDX], preLightData.layeredCoatRoughness);
preLightData.partLambdaV[BASE_LOBEA_IDX] = GetSmithJointGGXPartLambdaV(NdotV[DNLV_BASE_IDX], preLightData.layeredRoughnessT[0]);
preLightData.partLambdaV[BASE_LOBEB_IDX] = GetSmithJointGGXPartLambdaV(NdotV[DNLV_BASE_IDX], preLightData.layeredRoughnessT[1]);
#endif
} //...no anisotropy
//float3 H = (L + V) * invLenLV;
#endif // _MATERIAL_FEATURE_COAT
}
else
{
// No vlayering, just check if we need H:
if (HasFeatureFlag(bsdfData.materialFeatures, MATERIALFEATUREFLAGS_STACK_LIT_ANISOTROPY))
{
H = (L[0] + V[0]) * invLenLV;
}
}
} //...BSDF_SetupNormalsAndAngles
void CalculateAnisoAngles(BSDFData bsdfData, float3 H, float3 L, float3 V, out float TdotH, out float TdotL, out float BdotH, out float BdotL)
{
// For anisotropy we must not saturate these values
TdotH = dot(bsdfData.tangentWS, H);
TdotL = dot(bsdfData.tangentWS, L);
BdotH = dot(bsdfData.bitangentWS, H);
BdotL = dot(bsdfData.bitangentWS, L);
}
// This function apply BSDF. Assumes that NdotL is positive.
void BSDF(float3 inV, float3 inL, float inNdotL, float3 positionWS, PreLightData preLightData, BSDFData bsdfData,
out float3 diffuseLighting,
out float3 specularLighting)
{
float NdotL[NDOTLV_SIZE];
float NdotV[NDOTLV_SIZE];
// IMPORTANT: use DNLV_COAT_IDX and DNLV_BASE_IDX to index NdotL and NdotV since they can be sized 2
// either if we have to deal with refraction or if we use dual normal maps: NB_LV_DIR is for L or V,
// while NB_NORMALS is for N, but in the cases of NdotL, NdotV, they will be sized
// max(NB_LV_DIR, NB_NORMALS)
float3 L[NB_LV_DIR], V[NB_LV_DIR];
float3 N[NB_NORMALS];
float savedLdotH;
// ...only one needed: when vlayered, only top needed for input to ComputeAdding and even then, only if we recompute per light,
// otherwise, no vlayered and base one is used for a standard Fresnel calculation.
float3 H = (float3)0; // might not be needed if no refracted_angles option and no anisotropy...
float NdotH[NB_NORMALS]; // NdotH[NB_LV_DIR] not needed since it stays the same wrt a refraction along H itself.
float3 DV[TOTAL_NB_LOBES]; // BSDF results per lobe
// Note that we're never missing an initialization for the following as the arrays are sized 1 in the cases
// we use only the "bottom" parts (which are the same as the top: ie in case we have dual normal maps but no
// refracted angles to account for).
L[TOP_DIR_IDX] = inL;
V[TOP_DIR_IDX] = inV;
BSDF_SetupNormalsAndAngles(bsdfData, preLightData, inNdotL, L, V, N, NdotL, H, NdotH, savedLdotH, NdotV);
// TODO: with iridescence, will be optionally per light sample
if( IsVLayeredEnabled(bsdfData) )
{
#ifdef _MATERIAL_FEATURE_COAT
// --------------------------------------------------------------------
// VLAYERING:
// --------------------------------------------------------------------
if (HasFeatureFlag(bsdfData.materialFeatures, MATERIALFEATUREFLAGS_STACK_LIT_ANISOTROPY))
{
CalculateAnisoAngles(bsdfData, L, V, invLenLV, TdotH, TdotL, BdotH, BdotL);
CalculateAnisoAngles(bsdfData, H, L[BOTTOM_DIR_IDX], V[BOTTOM_DIR_IDX], TdotH, TdotL, BdotH, BdotL);
DV[BASE_LOBEA_IDX] = DV_SmithJointGGXAniso(TdotH, BdotH, NdotH[BASE_NORMAL_IDX], NdotV[BASE_NORMAL_IDX], TdotL, BdotL, NdotL[BASE_NORMAL_IDX],
DV[BASE_LOBEA_IDX] = DV_SmithJointGGXAniso(TdotH, BdotH, NdotH[BASE_NORMAL_IDX], NdotV[DNLV_BASE_IDX], TdotL, BdotL, NdotL[DNLV_BASE_IDX],
DV[BASE_LOBEB_IDX] = DV_SmithJointGGXAniso(TdotH, BdotH, NdotH[BASE_NORMAL_IDX], NdotV[BASE_NORMAL_IDX], TdotL, BdotL, NdotL[BASE_NORMAL_IDX],
DV[BASE_LOBEB_IDX] = DV_SmithJointGGXAniso(TdotH, BdotH, NdotH[BASE_NORMAL_IDX], NdotV[DNLV_BASE_IDX], TdotL, BdotL, NdotL[DNLV_BASE_IDX],
DV[COAT_LOBE_IDX] = DV_SmithJointGGX(topNdotH, topNdotL, topNdotV, preLightData.layeredCoatRoughness, preLightData.partLambdaV[COAT_LOBE_IDX]);
DV[COAT_LOBE_IDX] = DV_SmithJointGGX(NdotH[COAT_NORMAL_IDX], NdotL[DNLV_COAT_IDX], NdotV[DNLV_COAT_IDX], preLightData.layeredCoatRoughness, preLightData.partLambdaV[COAT_LOBE_IDX]);
#ifdef VLAYERED_RECOMPUTE_PERLIGHT
preLightData.partLambdaV[BASE_LOBEA_IDX] = GetSmithJointGGXPartLambdaV(NdotV[BASE_NORMAL_IDX], preLightData.layeredRoughnessT[0]);
preLightData.partLambdaV[BASE_LOBEB_IDX] = GetSmithJointGGXPartLambdaV(NdotV[BASE_NORMAL_IDX], preLightData.layeredRoughnessT[1]);
#endif
DV[COAT_LOBE_IDX] = DV_SmithJointGGX(topNdotH, topNdotL, topNdotV, preLightData.layeredCoatRoughness, preLightData.partLambdaV[COAT_LOBE_IDX]);
DV[BASE_LOBEA_IDX] = DV_SmithJointGGX(NdotH[BASE_NORMAL_IDX], NdotL[BASE_NORMAL_IDX], NdotV[BASE_NORMAL_IDX],
DV[COAT_LOBE_IDX] = DV_SmithJointGGX(NdotH[COAT_NORMAL_IDX], NdotL[DNLV_COAT_IDX], NdotV[DNLV_COAT_IDX], preLightData.layeredCoatRoughness, preLightData.partLambdaV[COAT_LOBE_IDX]);
DV[BASE_LOBEA_IDX] = DV_SmithJointGGX(NdotH[BASE_NORMAL_IDX], NdotL[DNLV_BASE_IDX], NdotV[DNLV_BASE_IDX],
DV[BASE_LOBEB_IDX] = DV_SmithJointGGX(NdotH[BASE_NORMAL_IDX], NdotL[BASE_NORMAL_IDX], NdotV[BASE_NORMAL_IDX],
DV[BASE_LOBEB_IDX] = DV_SmithJointGGX(NdotH[BASE_NORMAL_IDX], NdotL[DNLV_BASE_IDX], NdotV[DNLV_BASE_IDX],
IF_DEBUG( if(_DebugLobeMask.x == 0.0) DV[COAT_LOBE_IDX] = (float3)0; )
IF_DEBUG( if(_DebugLobeMask.y == 0.0) DV[BASE_LOBEA_IDX] = (float3)0; )
IF_DEBUG( if(_DebugLobeMask.z == 0.0) DV[BASE_LOBEB_IDX] = (float3)0; )
specularLighting = preLightData.vLayerEnergyCoeff[BOTTOM_VLAYER_IDX]
* lerp(DV[BASE_LOBEA_IDX] * preLightData.energyCompensationFactor[BASE_LOBEA_IDX],
// --------------------------------------------------------------------
// NO VLAYERING:
// --------------------------------------------------------------------
// TODO: Proper Fresnel
float3 F = F_Schlick(bsdfData.fresnel0, savedLdotH);
float3 H = (L + V) * invLenLV;
CalculateAnisoAngles(bsdfData, L, V, invLenLV, TdotH, TdotL, BdotH, BdotL);
CalculateAnisoAngles(bsdfData, H, L[0], V[0], TdotH, TdotL, BdotH, BdotL);
DV[0] = DV_SmithJointGGXAniso(TdotH, BdotH, NdotH[0], NdotV[0], TdotL, BdotL, NdotL[0],
bsdfData.roughnessAT, bsdfData.roughnessAB,
preLightData.partLambdaV[0]);
DV[0] = DV_SmithJointGGX(NdotH[0], NdotL[0], NdotV[0], bsdfData.roughnessAT, preLightData.partLambdaV[0]);
DV[1] = DV_SmithJointGGX(NdotH[0], NdotL[0], NdotV[0], bsdfData.roughnessBT, preLightData.partLambdaV[1]);
}
IF_DEBUG( if(_DebugLobeMask.y == 0.0) DV[BASE_LOBEA_IDX] = (float3)0; )
IF_DEBUG( if(_DebugLobeMask.z == 0.0) DV[BASE_LOBEB_IDX] = (float3)0; )
specularLighting = F * lerp(DV[0]*preLightData.energyCompensationFactor[BASE_LOBEA_IDX],
DV[1]*preLightData.energyCompensationFactor[BASE_LOBEB_IDX],
bsdfData.lobeMix);
diffuseLighting = diffuseTerm;
}//...BSDF
float3 EvaluateTransmission(BSDFData bsdfData, float3 transmittance, float NdotL, float NdotV, float LdotV, float attenuation)
{
DirectLighting lighting;
ZERO_INITIALIZE(DirectLighting, lighting);
// slnote : dual normal maps
//slnote dual map
float3 N; float unclampedNdotV;
EvaluateBSDF_GetNormalUnclampedNdotV(bsdfData, preLightData, V, N, unclampedNdotV);
//float3 N = bsdfData.normalWS;
distances.xyz = float3(dist, distSq, distRcp);
}
// slnote : dual normal maps
//slnote dual map
float3 N; float unclampedNdotV;
EvaluateBSDF_GetNormalUnclampedNdotV(bsdfData, preLightData, V, N, unclampedNdotV);
// Note: using influenceShapeType and projectionShapeType instead of (lightData|proxyData).shapeType allow to make compiler optimization in case the type is know (like for sky)
// slnote : dual normal maps
//slnote dual map
float3 influenceNormal; float unclampedNdotV;
EvaluateBSDF_GetNormalUnclampedNdotV(bsdfData, preLightData, V, influenceNormal, unclampedNdotV);
#ifdef VLAYERED_DEBUG
IF_FEATURE_COAT( if( (i == 0) && _DebugLobeMask.x == 0.0) continue; )
if( (i == (0 IF_FEATURE_COAT(+1))) && _DebugLobeMask.y == 0.0) continue;
if( (i == (1 IF_FEATURE_COAT(+1))) && _DebugLobeMask.z == 0.0) continue;
IF_FEATURE_COAT( if( (i == 0) && _DebugEnv LobeMask.x == 0.0) continue; )
if( (i == (0 IF_FEATURE_COAT(+1))) && _DebugEnv LobeMask.y == 0.0) continue;
if( (i == (1 IF_FEATURE_COAT(+1))) && _DebugEnv LobeMask.z == 0.0) continue;
// slnote : dual normal maps
//slnote dual map
//EvaluateLight_EnvIntersection(positionWS, bsdfData.normalWS, lightData, influenceShapeType, R[i], tempWeight[i]);
EvaluateLight_EnvIntersection(positionWS, influenceNormal, lightData, influenceShapeType, R[i], tempWeight[i]);
Stephane Laroche
6 年前