28 KiB
Common
Common.ush
添加结构体,主要用在材质的CustomNode里。
// Used by toon shading.
// Define a global custom data structure which can be filled by Custom node in material BP.
struct FToonShadingPerMaterialCustomData
{
// Toon specular
float3 ToonSpecularColor;
float ToonSpecularLocation;
float ToonSpecularSmoothness;
// Toon shadow
float3 ToonShadowColor;
float ToonShadowLocation;
float ToonShadowSmoothness;
float ToonForceShadow;
// Toon secondary shadow
float3 ToonSecondaryShadowColor;
float ToonSecondaryShadowLocation;
float ToonSecondaryShadowSmoothness;
// custom data, usually not used
float4 CustomData0;
float4 CustomData1;
float4 CustomData2;
float4 CustomData3;
};
static FToonShadingPerMaterialCustomData ToonShadingPerMaterialCustomData;
DeferredShadingCommon.ush
- 实现#Encode/Decode函数
- HasCustomGBufferData()函数添加对应的ToonShadingModel宏判断
- #FGBufferData新增变量
- #Encode/Decode GBufferData新增逻辑
- Metallic/Specualr/Roughness => ToonShadowLocation/ToonForceShadow/ToonShadowSmoothness
- AO => ToonSecondaryShadowLocation
- CustomData => ToonShadowColor/ToonSecondaryShadowSmoothness
- PrecomputedShadowFactors => ToonSecondaryShadowColor
#define GBUFFER_REFACTOR 0
以此关闭自动生成Encode/Decode GBufferData代码,并使用硬编码调用Encode/Decode GBufferData。#if WRITES_VELOCITY_TO_GBUFFER
=>#if GBUFFER_HAS_VELOCITY
,以此关闭写入VELOCITY到GBuffer中。
Encode/Decode函数
RGB655 to 8-bit RGB。 将R 256 => 64 ,GB 256 => 32。之后使用2个8bit浮点来存储:通道1存储R与G的头两位;通道2存储G的后3位与B。
float2 EncodeColorToRGB655(float3 Color)
{
const uint ChannelR = (1 << 6) - 1;
const uint ChannelG = (1 << 5) - 1;
const uint ChannelB = (1 << 5) - 1;
uint3 RoundedColor = uint3(float3(
round(Color.r * ChannelR),
round(Color.g * ChannelG),
round(Color.b * ChannelB)
));
return float2(
(RoundedColor.r << 2 | RoundedColor.g >> 3) / 255.0,
(RoundedColor.g << 5 | RoundedColor.b ) / 255.0
);
}
float3 DecodeRGB655ToColor(float2 RGB655)
{
const uint ChannelR = (1 << 6) - 1;
const uint ChannelG = (1 << 5) - 1;
const uint ChannelB = (1 << 5) - 1;
uint2 Inputs = uint2(round(RGB655 * 255.0));
uint BitBuffer = (Inputs.x << 8) | Inputs.y;
uint R = (BitBuffer & 0xFC00) >> 10;
uint G = (BitBuffer & 0x03E0) >> 5;
uint B = (BitBuffer & 0x001F);
return float3(R, G, B) * float3(1.0 / ChannelR, 1.0 / ChannelG, 1.0 / ChannelB);
}
FGBufferData新增变量
struct FGBufferData
{
...
// Toon specular
// 0..1, specular color
half3 ToonSpecularColor;
// 0..1, specular edge position
half ToonSpecularLocation;
// 0..1, specular edge smoothness
half ToonSpecularSmoothness;
// Toon shadow
// 0..1, shadow color
half3 ToonShadowColor;
// 0..1, shadow egde location
half ToonShadowLocation;
// 0..1, shadow edge smoothness
half ToonShadowSmoothness;
// 0..1, force shadow
half ToonForceShadow;
// Toon secondary shadow
// 0..1, secondary shadow color
float3 ToonSecondaryShadowColor;
// 0..1, secondary shadow edge location
float ToonSecondaryShadowLocation;
// 0..1, secondary shadow edge smoothness
float ToonSecondaryShadowSmoothness;
// Toon render
half3 ToonCalcShadowColor;
};
Encode/Decode GBufferData新增逻辑
void EncodeGBuffer(
FGBufferData GBuffer,
out float4 OutGBufferA,
out float4 OutGBufferB,
out float4 OutGBufferC,
out float4 OutGBufferD,
out float4 OutGBufferE,
out float4 OutGBufferVelocity,
float QuantizationBias = 0 // -0.5 to 0.5 random float. Used to bias quantization.
)
{
...
switch(GBuffer.ShadingModelID)
{
case SHADINGMODELID_TOON_BASE:
OutGBufferB.r = ToonShadingPerMaterialCustomData.ToonShadowLocation;
OutGBufferB.g = ToonShadingPerMaterialCustomData.ToonForceShadow;
OutGBufferB.b = ToonShadingPerMaterialCustomData.ToonShadowSmoothness;
OutGBufferC.a = ToonShadingPerMaterialCustomData.ToonSecondaryShadowLocation;
OutGBufferD.a = ToonShadingPerMaterialCustomData.ToonSecondaryShadowSmoothness;
OutGBufferD.rgb = ToonShadingPerMaterialCustomData.ToonShadowColor.rgb;
OutGBufferE.gba = ToonShadingPerMaterialCustomData.ToonSecondaryShadowColor.rgb;
break;
case SHADINGMODELID_TOON_PBR:
OutGBufferB.g = ToonShadingPerMaterialCustomData.ToonShadowLocation;
OutGBufferD.a = ToonShadingPerMaterialCustomData.ToonShadowSmoothness;
OutGBufferD.rgb = ToonShadingPerMaterialCustomData.ToonShadowColor.rgb;
OutGBufferE.gba = ToonShadingPerMaterialCustomData.ToonSpecularColor.rgb;
break;
case SHADINGMODELID_TOON_SKIN:
OutGBufferB.r = ToonShadingPerMaterialCustomData.ToonShadowLocation;
OutGBufferD.a = ToonShadingPerMaterialCustomData.ToonShadowSmoothness;
OutGBufferD.rgb = ToonShadingPerMaterialCustomData.ToonShadowColor.rgb;
break;
default:
break;
}
...
}
FGBufferData DecodeGBufferData(
float4 InGBufferA,
float4 InGBufferB,
float4 InGBufferC,
float4 InGBufferD,
float4 InGBufferE,
float4 InGBufferF,
float4 InGBufferVelocity,
float CustomNativeDepth,
uint CustomStencil,
float SceneDepth,
bool bGetNormalizedNormal,
bool bChecker)
{
FGBufferData GBuffer = (FGBufferData)0;
...
switch(GBuffer.ShadingModelID)
{
case SHADINGMODELID_TOON_BASE:
GBuffer.ToonShadowColor = InGBufferD.rgb;
GBuffer.ToonShadowLocation = InGBufferB.r;
GBuffer.ToonShadowSmoothness = InGBufferB.b;
GBuffer.ToonForceShadow = InGBufferB.g;
GBuffer.ToonSecondaryShadowColor = InGBufferE.gba;
GBuffer.ToonSecondaryShadowLocation = InGBufferC.a;
GBuffer.ToonSecondaryShadowSmoothness = InGBufferD.a;
GBuffer.Metallic = 0.0;
GBuffer.Specular = 1.0;
GBuffer.Roughness = 1.0;
GBuffer.GBufferAO = 0.0;
GBuffer.IndirectIrradiance = 1.0;
GBuffer.PrecomputedShadowFactors = !(GBuffer.SelectiveOutputMask & SKIP_PRECSHADOW_MASK) ? float4(InGBufferE.r, 1.0, 1.0, 1.0) : ((GBuffer.SelectiveOutputMask & ZERO_PRECSHADOW_MASK) ? 0 : 1);
GBuffer.StoredMetallic = 0.0;
GBuffer.StoredSpecular = 1.0;
break;
case SHADINGMODELID_TOON_PBR:
GBuffer.ToonSpecularColor = InGBufferE.gba;
GBuffer.ToonShadowColor = InGBufferD.rgb;
GBuffer.ToonShadowLocation = InGBufferB.g;
GBuffer.ToonShadowSmoothness = InGBufferD.a;
GBuffer.ToonSecondaryShadowColor = GBuffer.ToonShadowColor;
GBuffer.ToonForceShadow = 1.0;
GBuffer.ToonSpecularLocation = 1.0;
GBuffer.Specular = 1.0;
GBuffer.PrecomputedShadowFactors = !(GBuffer.SelectiveOutputMask & SKIP_PRECSHADOW_MASK) ? float4(InGBufferE.r, 1.0, 1.0, 1.0) : ((GBuffer.SelectiveOutputMask & ZERO_PRECSHADOW_MASK) ? 0 : 1);
break;
case SHADINGMODELID_TOON_SKIN:
GBuffer.ToonShadowColor = InGBufferD.rgb;
GBuffer.ToonShadowLocation = InGBufferB.r;
GBuffer.ToonShadowSmoothness = InGBufferD.a;
GBuffer.ToonSecondaryShadowColor = GBuffer.ToonShadowColor;
GBuffer.ToonForceShadow = 1.0;
GBuffer.Metallic = 0.0;
GBuffer.StoredMetallic = 0.0;
GBuffer.PrecomputedShadowFactors = !(GBuffer.SelectiveOutputMask & SKIP_PRECSHADOW_MASK) ? float4(InGBufferE.r, 1.0, 1.0, 1.0) : ((GBuffer.SelectiveOutputMask & ZERO_PRECSHADOW_MASK) ? 0 : 1);
break;
default:
break;
}
...
};
BasePass
BasePassPixelShader.usf
#if 1
=>#if GBUFFER_REFACTOR && 0
,以此关闭自动生成Encode/Decode GBufferData代码,并使用硬编码调用Encode/Decode GBufferData。- 在FPixelShaderInOut_MainPS()中添加写入FGBufferData逻辑。代码如下:
...
switch(GBuffer.ShadingModelID)
{
case SHADINGMODELID_TOON_BASE:
GBuffer.ToonShadowColor = ToonShadingPerMaterialCustomData.ToonShadowColor.rgb;
GBuffer.ToonShadowLocation = ToonShadingPerMaterialCustomData.ToonShadowLocation;
GBuffer.ToonShadowSmoothness = ToonShadingPerMaterialCustomData.ToonShadowSmoothness;
GBuffer.ToonForceShadow = ToonShadingPerMaterialCustomData.ToonForceShadow;
GBuffer.ToonSecondaryShadowColor = ToonShadingPerMaterialCustomData.ToonSecondaryShadowColor.rgb;
GBuffer.ToonSecondaryShadowLocation = ToonShadingPerMaterialCustomData.ToonSecondaryShadowLocation;
GBuffer.ToonSecondaryShadowSmoothness = ToonShadingPerMaterialCustomData.ToonSecondaryShadowSmoothness;
GBuffer.Specular = 1.0;
GBuffer.GBufferAO = 0.0;
GBuffer.PrecomputedShadowFactors.gba = 1;
break;
case SHADINGMODELID_TOON_PBR:
GBuffer.ToonSpecularColor = ToonShadingPerMaterialCustomData.ToonSpecularColor.rgb;
GBuffer.ToonShadowColor = ToonShadingPerMaterialCustomData.ToonShadowColor.rgb;
GBuffer.ToonShadowLocation = ToonShadingPerMaterialCustomData.ToonShadowLocation;
GBuffer.ToonShadowSmoothness = ToonShadingPerMaterialCustomData.ToonShadowSmoothness;
GBuffer.ToonSecondaryShadowColor = ToonShadingPerMaterialCustomData.ToonShadowColor.rgb;
GBuffer.ToonForceShadow = 1.0;
GBuffer.Specular = 1.0;
GBuffer.PrecomputedShadowFactors.gba = 1;
break;
case SHADINGMODELID_TOON_SKIN:
GBuffer.ToonShadowColor = ToonShadingPerMaterialCustomData.ToonShadowColor.rgb;
GBuffer.ToonShadowLocation = ToonShadingPerMaterialCustomData.ToonShadowLocation;
GBuffer.ToonShadowSmoothness = ToonShadingPerMaterialCustomData.ToonShadowSmoothness;
GBuffer.ToonSecondaryShadowColor = ToonShadingPerMaterialCustomData.ToonShadowColor.rgb;
GBuffer.ToonForceShadow = 1.0;
GBuffer.PrecomputedShadowFactors.g = 1;
break;
default:
break;
}
...
Lighting
ShadingModels
ShadingCommon.ush
添加ShadingModelID宏:
- SHADINGMODELID_TOON_BASE 13
- SHADINGMODELID_TOON_PBR 14
- SHADINGMODELID_TOON_SKIN 15
- SHADINGMODELID_NUM 16
判断是否是IsToonShadingModel:
bool IsToonShadingModel(uint ShadingModel)
{
uint4 ToonShadingModels = uint4(SHADINGMODELID_TOON_BASE, SHADINGMODELID_TOON_PBR, SHADINGMODELID_TOON_SKIN, 0xFF);
return any(ShadingModel.xxxx == ToonShadingModels);
}
DeferredLightingCommon.ush
修改了AccumulateDynamicLighting()的逻辑。
FLightAccumulator AccumulateDynamicLighting(
float3 TranslatedWorldPosition, half3 CameraVector, FGBufferData GBuffer, half AmbientOcclusion, uint ShadingModelID,
FDeferredLightData LightData, half4 LightAttenuation, float Dither, uint2 SVPos,
inout float SurfaceShadow)
{
FLightAccumulator LightAccumulator = (FLightAccumulator)0;
half3 V = -CameraVector;
half3 N = GBuffer.WorldNormal;
BRANCH if( GBuffer.ShadingModelID == SHADINGMODELID_CLEAR_COAT && CLEAR_COAT_BOTTOM_NORMAL)
{
const float2 oct1 = ((float2(GBuffer.CustomData.a, GBuffer.CustomData.z) * 4) - (512.0/255.0)) + UnitVectorToOctahedron(GBuffer.WorldNormal);
N = OctahedronToUnitVector(oct1);
}
float3 L = LightData.Direction; // Already normalized
float3 ToLight = L;
float3 MaskedLightColor = LightData.Color;
float LightMask = 1;
if (LightData.bRadialLight)
{
LightMask = GetLocalLightAttenuation( TranslatedWorldPosition, LightData, ToLight, L );
MaskedLightColor *= LightMask;
}
LightAccumulator.EstimatedCost += 0.3f; // running the PixelShader at all has a cost
BRANCH
if( LightMask > 0 )
{
FShadowTerms Shadow;
Shadow.SurfaceShadow = AmbientOcclusion;
Shadow.TransmissionShadow = 1;
Shadow.TransmissionThickness = 1;
Shadow.HairTransmittance.OpaqueVisibility = 1;
const float ContactShadowOpacity = GBuffer.CustomData.a;
GetShadowTerms(GBuffer.Depth, GBuffer.PrecomputedShadowFactors, GBuffer.ShadingModelID, ContactShadowOpacity,
LightData, TranslatedWorldPosition, L, LightAttenuation, Dither, Shadow);
SurfaceShadow = Shadow.SurfaceShadow;
LightAccumulator.EstimatedCost += 0.3f; // add the cost of getting the shadow terms
#if SHADING_PATH_MOBILE
const bool bNeedsSeparateSubsurfaceLightAccumulation = UseSubsurfaceProfile(GBuffer.ShadingModelID);
FDirectLighting Lighting = (FDirectLighting)0;
half NoL = max(0, dot(GBuffer.WorldNormal, L));
#if TRANSLUCENCY_NON_DIRECTIONAL
NoL = 1.0f;
#endif
Lighting = EvaluateBxDF(GBuffer, N, V, L, NoL, Shadow);
Lighting.Specular *= LightData.SpecularScale;
LightAccumulator_AddSplit( LightAccumulator, Lighting.Diffuse, Lighting.Specular, Lighting.Diffuse, MaskedLightColor * Shadow.SurfaceShadow, bNeedsSeparateSubsurfaceLightAccumulation );
LightAccumulator_AddSplit( LightAccumulator, Lighting.Transmission, 0.0f, Lighting.Transmission, MaskedLightColor * Shadow.TransmissionShadow, bNeedsSeparateSubsurfaceLightAccumulation );
#else // SHADING_PATH_MOBILE
//修改了这里
bool UseToonShadow = IsToonShadingModel(GBuffer.ShadingModelID);
BRANCH
if( Shadow.SurfaceShadow + Shadow.TransmissionShadow > 0 || UseToonShadow)//修改结束
{
const bool bNeedsSeparateSubsurfaceLightAccumulation = UseSubsurfaceProfile(GBuffer.ShadingModelID);
//修改了这里
BRANCH
if(UseToonShadow)
{
float NoL = dot(N, L);
float ToonNoL = min(NoL, GBuffer.ToonForceShadow);
//合并SurfaceShadow以及Transmision Shadow
Shadow.SurfaceShadow = min(Shadow.SurfaceShadow, Shadow.TransmissionShadow);
//根据ToonShadowSmoothness、ToonShadowLocation、NoL计算阴影亮度,最后计算主阴影颜色。
float RangeHalf = GBuffer.ToonShadowSmoothness * 0.5;
float RangeMin = max(0.0, GBuffer.ToonShadowLocation - RangeHalf);
float RangeMax = min(1.0, GBuffer.ToonShadowLocation + RangeHalf);
float ShadowIntensity = Shadow.SurfaceShadow * smoothstep(RangeMin, RangeMax, ToonNoL);
GBuffer.ToonCalcShadowColor = lerp(GBuffer.ToonShadowColor * LightData.SpecularScale, (1.0).xxx, ShadowIntensity);
//计算次级阴影颜色,并最终合成。
RangeHalf = GBuffer.ToonSecondaryShadowSmoothness * 0.5;
RangeMin = max(0.0, GBuffer.ToonSecondaryShadowLocation - RangeHalf);
RangeMax = min(1.0, GBuffer.ToonSecondaryShadowLocation + RangeHalf);
ShadowIntensity = Shadow.SurfaceShadow * smoothstep(RangeMin, RangeMax, ToonNoL);
GBuffer.ToonCalcShadowColor = lerp(GBuffer.ToonSecondaryShadowColor * LightData.SpecularScale, GBuffer.ToonCalcShadowColor, ShadowIntensity);
}
//修改结束
#if NON_DIRECTIONAL_DIRECT_LIGHTING
float Lighting;
if( LightData.bRectLight )
{
FRect Rect = GetRect( ToLight, LightData );
Lighting = IntegrateLight( Rect );
}
else
{
FCapsuleLight Capsule = GetCapsule( ToLight, LightData );
Lighting = IntegrateLight( Capsule, LightData.bInverseSquared );
}
float3 LightingDiffuse = Diffuse_Lambert( GBuffer.DiffuseColor ) * Lighting;
LightAccumulator_AddSplit(LightAccumulator, LightingDiffuse, 0.0f, 0, MaskedLightColor * Shadow.SurfaceShadow, bNeedsSeparateSubsurfaceLightAccumulation);
#else
FDirectLighting Lighting;
if (LightData.bRectLight)
{
FRect Rect = GetRect( ToLight, LightData );
const FRectTexture SourceTexture = ConvertToRectTexture(LightData);
#if REFERENCE_QUALITY
Lighting = IntegrateBxDF( GBuffer, N, V, Rect, Shadow, SourceTexture, SVPos );
#else
Lighting = IntegrateBxDF( GBuffer, N, V, Rect, Shadow, SourceTexture);
#endif
}
else
{
FCapsuleLight Capsule = GetCapsule( ToLight, LightData );
#if REFERENCE_QUALITY
Lighting = IntegrateBxDF( GBuffer, N, V, Capsule, Shadow, SVPos );
#else
Lighting = IntegrateBxDF( GBuffer, N, V, Capsule, Shadow, LightData.bInverseSquared );
#endif
}
//修改了这里
float SurfaceShadow = UseToonShadow ? 1.0 : Shadow.SurfaceShadow;
float TransmissionShadow = UseToonShadow ? 1.0 : Shadow.TransmissionShadow;
Lighting.Specular *= UseToonShadow ? GBuffer.ToonSpecularColor : LightData.SpecularScale;
LightAccumulator_AddSplit( LightAccumulator, Lighting.Diffuse, Lighting.Specular, Lighting.Diffuse, MaskedLightColor * SurfaceShadow, bNeedsSeparateSubsurfaceLightAccumulation );
LightAccumulator_AddSplit( LightAccumulator, Lighting.Transmission, 0.0f, Lighting.Transmission, MaskedLightColor * TransmissionShadow, bNeedsSeparateSubsurfaceLightAccumulation );
//修改结束
LightAccumulator.EstimatedCost += 0.4f; // add the cost of the lighting computations (should sum up to 1 form one light)
#endif
}
#endif // SHADING_PATH_MOBILE
}
return LightAccumulator;
}
ShadingModels.ush
float3 ToonSpecular(float ToonSpecularLocation, float ToonSpecularSmoothness, float3 ToonSpecularColor, float NoL)
{
float ToonSpecularRangeHalf = ToonSpecularSmoothness * 0.5;
float ToonSpecularRangeMin = ToonSpecularLocation - ToonSpecularRangeHalf;
float ToonSpecularRangeMax = ToonSpecularLocation + ToonSpecularRangeHalf;
return smoothstep(ToonSpecularRangeMin, ToonSpecularRangeMax, NoL) * ToonSpecularColor;
}
创建了ToonCustomBxDF(SHADINGMODELID_TOON_BASE)与ToonLitBxDF(SHADINGMODELID_TOON_PBR、SHADINGMODELID_TOON_SKIN)2个ShadingModel函数。
ToonCustomBxDF的修改
Diffuse里面乘以之前在DeferredShadingCommon.ush中计算好的ShadowColor(已经计算了NoL)
Lighting.Diffuse *= AreaLight.FalloffColor * (Falloff * NoL);
=>
Lighting.Diffuse *= AreaLight.FalloffColor * Falloff * GBuffer.ToonCalcShadowColor;
Speuclar直接归零,具体是在BasePass阶段进行计算了。
Lighting.Specular = 0;
ToonLitBxDF的修改
Diffuse里面乘以之前在DeferredShadingCommon.ush中计算好的ShadowColor(已经计算了NoL)
Lighting.Diffuse *= AreaLight.FalloffColor * (Falloff * NoL);
=>
Lighting.Diffuse *= AreaLight.FalloffColor * Falloff * GBuffer.ToonCalcShadowColor;
Speuclar最后乘以了Shadow.SurfaceShadow
Lighting.Specular *= Shadow.SurfaceShadow;
FDirectLighting ToonLitBxDF( FGBufferData GBuffer, half3 N, half3 V, half3 L, float Falloff, half NoL, FAreaLight AreaLight, FShadowTerms Shadow )
{
BxDFContext Context;
FDirectLighting Lighting;
#if SUPPORTS_ANISOTROPIC_MATERIALS
bool bHasAnisotropy = HasAnisotropy(GBuffer.SelectiveOutputMask);
#else
bool bHasAnisotropy = false;
#endif
float NoV, VoH, NoH;
BRANCH
if (bHasAnisotropy)
{
half3 X = GBuffer.WorldTangent;
half3 Y = normalize(cross(N, X));
Init(Context, N, X, Y, V, L);
NoV = Context.NoV;
VoH = Context.VoH;
NoH = Context.NoH;
}
else
{
#if SHADING_PATH_MOBILE
InitMobile(Context, N, V, L, NoL);
#else
Init(Context, N, V, L);
#endif
NoV = Context.NoV;
VoH = Context.VoH;
NoH = Context.NoH;
SphereMaxNoH(Context, AreaLight.SphereSinAlpha, true);
}
Context.NoV = saturate(abs( Context.NoV ) + 1e-5);
#if MATERIAL_ROUGHDIFFUSE
// Chan diffuse model with roughness == specular roughness. This is not necessarily a good modelisation of reality because when the mean free path is super small, the diffuse can in fact looks rougher. But this is a start.
// Also we cannot use the morphed context maximising NoH as this is causing visual artefact when interpolating rough/smooth diffuse response.
Lighting.Diffuse = Diffuse_Chan(GBuffer.DiffuseColor, Pow4(GBuffer.Roughness), NoV, NoL, VoH, NoH, GetAreaLightDiffuseMicroReflWeight(AreaLight));
#else
Lighting.Diffuse = Diffuse_Lambert(GBuffer.DiffuseColor);
#endif
// Toon Diffuse
Lighting.Diffuse *= AreaLight.FalloffColor * Falloff * GBuffer.ToonCalcShadowColor;
BRANCH
if (bHasAnisotropy)
{
//Lighting.Specular = GBuffer.WorldTangent * .5f + .5f;
Lighting.Specular = AreaLight.FalloffColor * (Falloff * NoL) * SpecularGGX(GBuffer.Roughness, GBuffer.Anisotropy, GBuffer.SpecularColor, Context, NoL, AreaLight);
}
else
{
if( IsRectLight(AreaLight) )
{
Lighting.Specular = RectGGXApproxLTC(GBuffer.Roughness, GBuffer.SpecularColor, N, V, AreaLight.Rect, AreaLight.Texture);
}
else
{
// Toon specular
Lighting.Specular = AreaLight.FalloffColor * (Falloff * NoL) * SpecularGGX(GBuffer.Roughness, GBuffer.SpecularColor, Context, NoL, AreaLight);
}
}
Lighting.Specular *= Shadow.SurfaceShadow;
FBxDFEnergyTerms EnergyTerms = ComputeGGXSpecEnergyTerms(GBuffer.Roughness, Context.NoV, GBuffer.SpecularColor);
// Add energy presevation (i.e. attenuation of the specular layer onto the diffuse component
Lighting.Diffuse *= ComputeEnergyPreservation(EnergyTerms);
// Add specular microfacet multiple scattering term (energy-conservation)
Lighting.Specular *= ComputeEnergyConservation(EnergyTerms);
Lighting.Transmission = 0;
return Lighting;
}
FDirectLighting ToonCustomBxDF( FGBufferData GBuffer, half3 N, half3 V, half3 L, float Falloff, half NoL, FAreaLight AreaLight, FShadowTerms Shadow )
{
BxDFContext Context;
FDirectLighting Lighting;
float NoV, VoH, NoH;
#if SHADING_PATH_MOBILE
InitMobile(Context, N, V, L, NoL);
#else
Init(Context, N, V, L);
#endif
NoV = Context.NoV;
VoH = Context.VoH;
NoH = Context.NoH;
SphereMaxNoH(Context, AreaLight.SphereSinAlpha, true);
Context.NoV = saturate(abs( Context.NoV ) + 1e-5);
#if MATERIAL_ROUGHDIFFUSE
// Chan diffuse model with roughness == specular roughness. This is not necessarily a good modelisation of reality because when the mean free path is super small, the diffuse can in fact looks rougher. But this is a start.
// Also we cannot use the morphed context maximising NoH as this is causing visual artefact when interpolating rough/smooth diffuse response.
Lighting.Diffuse = Diffuse_Chan(GBuffer.DiffuseColor, Pow4(GBuffer.Roughness), NoV, NoL, VoH, NoH, GetAreaLightDiffuseMicroReflWeight(AreaLight));
#else
Lighting.Diffuse = Diffuse_Lambert(GBuffer.DiffuseColor);
#endif
// Toon Diffuse
Lighting.Diffuse *= AreaLight.FalloffColor * Falloff * GBuffer.ToonCalcShadowColor;
// Toon specular
// Lighting.Specular = AreaLight.FalloffColor * (Falloff * NoL) * ToonSpecular(GBuffer.ToonSpecularLocation, GBuffer.ToonSpecularSmoothness, GBuffer.ToonSpecularColor, NoL);
// Lighting.Specular *= Shadow.SurfaceShadow;
// FBxDFEnergyTerms EnergyTerms = ComputeGGXSpecEnergyTerms(GBuffer.Roughness, Context.NoV, GBuffer.SpecularColor);
// Add energy presevation (i.e. attenuation of the specular layer onto the diffuse component
// Lighting.Diffuse *= ComputeEnergyPreservation(EnergyTerms);
Lighting.Specular = 0;
Lighting.Transmission = 0;
return Lighting;
}
FDirectLighting IntegrateBxDF( FGBufferData GBuffer, half3 N, half3 V, half3 L, float Falloff, half NoL, FAreaLight AreaLight, FShadowTerms Shadow )
{
switch( GBuffer.ShadingModelID )
{
case SHADINGMODELID_DEFAULT_LIT:
case SHADINGMODELID_SINGLELAYERWATER:
case SHADINGMODELID_THIN_TRANSLUCENT:
return DefaultLitBxDF( GBuffer, N, V, L, Falloff, NoL, AreaLight, Shadow );
case SHADINGMODELID_SUBSURFACE:
return SubsurfaceBxDF( GBuffer, N, V, L, Falloff, NoL, AreaLight, Shadow );
case SHADINGMODELID_PREINTEGRATED_SKIN:
return PreintegratedSkinBxDF( GBuffer, N, V, L, Falloff, NoL, AreaLight, Shadow );
case SHADINGMODELID_CLEAR_COAT:
return ClearCoatBxDF( GBuffer, N, V, L, Falloff, NoL, AreaLight, Shadow );
case SHADINGMODELID_SUBSURFACE_PROFILE:
return SubsurfaceProfileBxDF( GBuffer, N, V, L, Falloff, NoL, AreaLight, Shadow );
case SHADINGMODELID_TWOSIDED_FOLIAGE:
return TwoSidedBxDF( GBuffer, N, V, L, Falloff, NoL, AreaLight, Shadow );
case SHADINGMODELID_HAIR:
return HairBxDF( GBuffer, N, V, L, Falloff, NoL, AreaLight, Shadow );
case SHADINGMODELID_CLOTH:
return ClothBxDF( GBuffer, N, V, L, Falloff, NoL, AreaLight, Shadow );
case SHADINGMODELID_EYE:
return EyeBxDF( GBuffer, N, V, L, Falloff, NoL, AreaLight, Shadow );
case SHADINGMODELID_TOON_BASE:
return ToonCustomBxDF( GBuffer, N, V, L, Falloff, NoL, AreaLight, Shadow );
case SHADINGMODELID_TOON_PBR:
case SHADINGMODELID_TOON_SKIN:
return ToonLitBxDF( GBuffer, N, V, L, Falloff, NoL, AreaLight, Shadow );
default:
return (FDirectLighting)0;
}
}
DeferredLightPixelShaders.usf
在DeferredLightPixelMain()中添加逻辑:
- 非卡通材质正常渲染。
- 材质材质只有在LightingChannel = 2时才会计算卡通光影效果。
bool UseToonShadow = IsToonShadingModel(ScreenSpaceData.GBuffer.ShadingModelID);
// LightingChannel Toon Shading only calculate light of LightingChannel = 2
BRANCH if (!UseToonShadow || (UseToonShadow && DeferredLightUniforms.LightingChannelMask & 0x4))
{
const float SceneDepth = CalcSceneDepth(InputParams.ScreenUV);
const FDerivedParams DerivedParams = GetDerivedParams(InputParams, SceneDepth);
FDeferredLightData LightData = InitDeferredLightFromUniforms(CURRENT_LIGHT_TYPE);
UpdateLightDataColor(LightData, InputParams, DerivedParams);
#if USE_HAIR_COMPLEX_TRANSMITTANCE
if (ScreenSpaceData.GBuffer.ShadingModelID == SHADINGMODELID_HAIR && ShouldUseHairComplexTransmittance(ScreenSpaceData.GBuffer))
{
LightData.HairTransmittance = EvaluateDualScattering(ScreenSpaceData.GBuffer, DerivedParams.CameraVector, -DeferredLightUniforms.Direction);
}
#endif
float Dither = InterleavedGradientNoise(InputParams.PixelPos, View.StateFrameIndexMod8);
float SurfaceShadow = 1.0f;
float4 LightAttenuation = GetLightAttenuationFromShadow(InputParams, SceneDepth);
float4 Radiance = GetDynamicLighting(DerivedParams.TranslatedWorldPosition, DerivedParams.CameraVector, ScreenSpaceData.GBuffer, ScreenSpaceData.AmbientOcclusion, ScreenSpaceData.GBuffer.ShadingModelID, LightData, LightAttenuation, Dither, uint2(InputParams.PixelPos), SurfaceShadow);
OutColor += Radiance;
}
PostProcess
ToneMapping
c++部分主要修改了:
- PostProcessing.cpp
- PostProcessTonemap.cpp
- PostProcessTonemap.h
实现向ToneMaper Shader传递 TRDGUniformBufferRef<FSceneTextureUniformParameters>
的功能
之后再PostProcessTonemap.usf中,对CustomStencil进行判断,如果为true,则直接返回之前渲染结果。实际上BufferVisualization里根本看不出来。
#include "DeferredShadingCommon.ush"
// pixel shader entry point
void MainPS(
in noperspective float2 UV : TEXCOORD0,
in noperspective float2 InVignette : TEXCOORD1,
in noperspective float4 GrainUV : TEXCOORD2,
in noperspective float2 ScreenPos : TEXCOORD3,
in noperspective float2 FullViewUV : TEXCOORD4,
float4 SvPosition : SV_POSITION, // after all interpolators
out float4 OutColor : SV_Target0
#if OUTPUT_LUMINANCE
, out float OutLuminance: SV_Target1
#endif
)
{
float Luminance;
FGBufferData SamplerBuffer = GetGBufferData(UV * View.ResolutionFractionAndInv.x, false);
if (SamplerBuffer.CustomStencil > 1.0f && abs(SamplerBuffer.CustomDepth - SamplerBuffer.Depth) < 1)
{
OutColor = SampleSceneColor(UV);
}
else
{
OutColor = TonemapCommonPS(UV, InVignette, GrainUV, ScreenPos, FullViewUV, SvPosition, Luminance);
}
#if OUTPUT_LUMINANCE
OutLuminance = Luminance;
#endif
}
PostProcessCombineLUT.usf
主要移植了UE4版本的LUT,以此保证效果统一。
其他
GpuSkinCacheComputeShader.usf
注释2行代码,用处不明。
#if GPUSKIN_MORPH_BLEND
{
Intermediates.UnpackedPosition += Unpacked.DeltaPosition;
// calc new normal by offseting it with the delta
LocalTangentZ = normalize( LocalTangentZ + Unpacked.DeltaTangentZ);
// derive the new tangent by orthonormalizing the new normal against
// the base tangent vector (assuming these are normalized)
LocalTangentX = normalize( LocalTangentX - (dot(LocalTangentX, LocalTangentZ) * LocalTangentZ) );
}#else
#if GPUSKIN_APEX_CLOTH
=>
#if GPUSKIN_MORPH_BLEND
{
Intermediates.UnpackedPosition += Unpacked.DeltaPosition;
// calc new normal by offseting it with the delta
//LocalTangentZ = normalize( LocalTangentZ + Unpacked.DeltaTangentZ);
// derive the new tangent by orthonormalizing the new normal against
// the base tangent vector (assuming these are normalized)
//LocalTangentX = normalize( LocalTangentX - (dot(LocalTangentX, LocalTangentZ) * LocalTangentZ) );
}#else
#if GPUSKIN_APEX_CLOTH