Files
UnrealEngine/Engine/Shaders/Private/MeshDecals.usf
2025-05-18 13:04:45 +08:00

278 lines
11 KiB
HLSL

// Copyright Epic Games, Inc. All Rights Reserved.
/*=============================================================================
MeshDecals.usf: Vertex/Hull/Domain/Pixel shader for computing a mesh decal.
=============================================================================*/
#include "Common.ush"
#if SHADING_PATH_MOBILE
// Reroute MobileSceneTextures uniform buffer references to the base pass uniform buffer
#define MobileSceneTextures MobileBasePass.SceneTextures
#define EyeAdaptationStruct MobileBasePass
#define SubstrateStruct MobileBasePass.SubstratePublic
#else
#define SceneTexturesStruct DecalPass.SceneTextures
#define EyeAdaptationStruct DecalPass
#define SubstrateStruct DecalPass.SubstratePublic
#endif
#include "Substrate/Substrate.ush"
#include "DecalCommon.ush"
#include "/Engine/Generated/Material.ush"
#include "/Engine/Generated/VertexFactory.ush"
#if PIXELSHADER
#define MOBILE_SUBSTRATE_USES_BLENDABLE_GBUFFER (SUBSTRATE_ENABLED && (SHADING_PATH_MOBILE || SUBTRATE_GBUFFER_FORMAT==0)) // When using forward shading, the base pass pixel shader is used with blending.
#if MOBILE_SUBSTRATE_USES_BLENDABLE_GBUFFER
#define MATERIAL_SUBSTRATE_OPAQUE_PRECOMPUTED_LIGHTING 0
#define SUBSTRATE_MATERIAL_EXPORT_REQUESTED 1
#include "/Engine/Private/Substrate/SubstrateExport.ush"
#endif
#endif // PIXELSHADER
// If virtual texture feedback is enabled then use early depth test so that UAV feedback buffer writes respect the depth test
#if MATERIAL_VIRTUALTEXTURE_FEEDBACK
#if COMPILER_SUPPORTS_DEPTHSTENCIL_EARLYTEST_LATEWRITE
// If we support early depth test with late write behaviour then use it since we may be using discard, or modifying depth
#define PIXELSHADER_EARLYDEPTHSTENCIL DEPTHSTENCIL_EARLYTEST_LATEWRITE
#elif !OUTPUT_PIXEL_DEPTH_OFFSET
// Otherwise we can only use early depth test if not modifying depth
// Modifying depth will trigger the slow path where we write feedback to UAV even where depth occluded!
#define PIXELSHADER_EARLYDEPTHSTENCIL EARLYDEPTHSTENCIL
#endif
#endif
// Additional guard to remove all struct usage if empty to avoid platform conflicts.
// This define can be removed if additional data is added to the interpolants struct
#define NEED_MESH_DECAL_INTERPOLATORS USE_WORLD_POSITION_EXCLUDING_SHADER_OFFSETS
struct FMeshDecalInterpolants
{
#if USE_WORLD_POSITION_EXCLUDING_SHADER_OFFSETS
float3 PixelPositionExcludingWPO : TEXCOORD8; // Arbitrary free slot
#endif
};
struct FMeshDecalVSToPS
{
FVertexFactoryInterpolantsVSToPS FactoryInterpolants;
#if NEED_MESH_DECAL_INTERPOLATORS
FMeshDecalInterpolants MeshDecalInterpolants;
#endif
float4 Position : SV_POSITION;
};
#define VS_OUTPUT_TYPE FMeshDecalVSToPS
#if VERTEXSHADER
/** transform mesh as normal */
void MainVS(
FVertexFactoryInput Input,
out VS_OUTPUT_TYPE Output,
out FStereoVSOutput StereoOutput
#if USE_GLOBAL_CLIP_PLANE
, out float OutGlobalClipPlaneDistance : SV_ClipDistance
#endif
)
{
StereoSetupVF(Input, StereoOutput);
FVertexFactoryIntermediates VFIntermediates = GetVertexFactoryIntermediates(Input);
float4 WorldPosition = VertexFactoryGetWorldPosition(Input, VFIntermediates);
float3x3 TangentToLocal = VertexFactoryGetTangentToLocal(Input, VFIntermediates);
#if USE_WORLD_POSITION_EXCLUDING_SHADER_OFFSETS
Output.MeshDecalInterpolants.PixelPositionExcludingWPO = WorldPosition.xyz;
#endif
FMaterialVertexParameters VertexParameters = GetMaterialVertexParameters(Input, VFIntermediates, WorldPosition.xyz, TangentToLocal);
// Isolate instructions used for world position offset on xbox 360,
// As these cause the optimizer to generate different position calculating instructions in each pass, resulting in self-z-fighting.
// This is only necessary for shaders used in passes that have depth testing enabled.
{
WorldPosition.xyz += GetMaterialWorldPositionOffset(VertexParameters);
ApplyMaterialFirstPersonTransform(VertexParameters, WorldPosition.xyz);
}
Output.Position = mul(WorldPosition, ResolvedView.TranslatedWorldToClip);
Output.FactoryInterpolants = VertexFactoryGetInterpolantsVSToPS(Input, VFIntermediates, VertexParameters);
#if USE_GLOBAL_CLIP_PLANE
OutGlobalClipPlaneDistance = dot(ResolvedView.GlobalClippingPlane, float4(WorldPosition.xyz, 1));
#endif
#if HAS_INVERTED_Z_BUFFER
// Move all geometry a small amount towards the camera to avoid z-fighting.
// Assuming a reverse z buffer this pushes the near plane a fixed small distance.
Output.Position.z += ResolvedView.DecalDepthBias;
#endif
}
#endif // VERTEXSHADER
#if PIXELSHADER
// is called in MainPS() from PixelShaderOutputCommon.usf
void FPixelShaderInOut_MainPS(
FVertexFactoryInterpolantsVSToPS FactoryInterpolants,
#if NEED_MESH_DECAL_INTERPOLATORS
FMeshDecalInterpolants MeshDecalInterpolants,
#endif
inout FPixelShaderIn In,
inout FPixelShaderOut Out,
uint EyeIndex)
{
FMaterialPixelParameters MaterialParameters = GetMaterialPixelParameters(FactoryInterpolants, In.SvPosition);
FPixelMaterialInputs PixelMaterialInputs;
#if USE_WORLD_POSITION_EXCLUDING_SHADER_OFFSETS
{
float4 ScreenPosition = SvPositionToResolvedScreenPosition(In.SvPosition);
float3 TranslatedWorldPosition = SvPositionToResolvedTranslatedWorld(In.SvPosition);
CalcMaterialParametersEx(MaterialParameters, PixelMaterialInputs, In.SvPosition, ScreenPosition, In.bIsFrontFace, TranslatedWorldPosition, MeshDecalInterpolants.PixelPositionExcludingWPO);
}
#else
{
float4 ScreenPosition = SvPositionToResolvedScreenPosition(In.SvPosition);
float3 TranslatedWorldPosition = SvPositionToResolvedTranslatedWorld(In.SvPosition);
CalcMaterialParametersEx(MaterialParameters, PixelMaterialInputs, In.SvPosition, ScreenPosition, In.bIsFrontFace, TranslatedWorldPosition, TranslatedWorldPosition);
}
#endif
#if SUBSTRATE_ENABLED
FSubstratePixelHeader SubstrateHeader = MaterialParameters.GetFrontSubstrateHeader();
const float MaterialAO = GetMaterialAmbientOcclusion(PixelMaterialInputs);
SubstrateHeader.IrradianceAO.MaterialAO = MaterialAO;
#if MOBILE_SUBSTRATE_USES_BLENDABLE_GBUFFER
float3 EmissiveColor = 0.0f.xxx;
float Opacity = 0.0f;
FGBufferData DBufferData;
if (SubstrateHeader.SubstrateTree.BSDFCount > 0)
{
const FSubstrateIntegrationSettings Settings = InitSubstrateIntegrationSettings(false /*bForceFullyRough*/, false /*bRoughDiffuseEnabled*/, 0, false/*bRoughnessTracking*/);
const float3 SurfaceWorldNormal = MaterialParameters.TangentToWorld[2].xyz;
FExportResult Export = SubstrateMaterialExportOut(
Settings,
SubstrateHeader,
PixelMaterialInputs.GetFrontSubstrateData(),
SurfaceWorldNormal,
MaterialParameters.WorldPosition_CamRelative,
0.0f /*MobileShadingPathCurvature*/);
// Either propagate the BSDF opacity, or use the one for AlphaComposite (premultiplied alpha)
float CoverageOverBackground = Export.Coverage;
#if SUBSTRATE_USE_PREMULTALPHA_OVERRIDE // AlphaComposite - Premultiplied alpha blending
CoverageOverBackground = GetMaterialOpacity(PixelMaterialInputs);
#endif
Opacity = CoverageOverBackground;
EmissiveColor = Export.EmissiveLuminance;
FGBufferData DBufferData = (FGBufferData)0;
DBufferData.WorldNormal = Export.WorldNormal;
DBufferData.BaseColor = Export.BaseColor;
DBufferData.Metallic = Export.Metallic;
DBufferData.Specular = Export.Specular;
DBufferData.Roughness = Export.Roughness;
DBufferData.CustomData = 0;
DBufferData.IndirectIrradiance = 0;
DBufferData.PrecomputedShadowFactors = 1;
DBufferData.GBufferAO = MaterialAO;
DBufferData.ShadingModelID = Export.ShadingModelID;
DBufferData.SelectiveOutputMask = 0;
DBufferData.PerObjectGBufferData = 1;
DBufferData.DiffuseIndirectSampleOcclusion = 0;
DBufferData.Velocity = 0;
DecalCommonOutput(In, Out, EmissiveColor, Opacity, DBufferData);
}
#else
float Coverage = 0.0;
if (SubstrateHeader.SubstrateTree.BSDFCount > 0)
{
const float3 V = MaterialParameters.CameraVector;
// Update tree (coverage/transmittance/luminace weights)
const FSubstrateIntegrationSettings Settings = InitSubstrateIntegrationSettings(false /*bForceFullyRough*/, false /*bRoughDiffuseEnabled*/, 0, false/*bRoughnessTracking*/);
SubstrateHeader.SubstrateUpdateTree(V, Settings);
// Either propagate the BSDF opacity, or use the one for AlphaComposite (premultiplied alpha)
float CoverageOverBackground = SubstrateHeader.SubstrateTree.BSDFs[0].Coverage;
#if SUBSTRATE_USE_PREMULTALPHA_OVERRIDE // AlphaComposite - Premultiplied alpha blending
CoverageOverBackground = GetMaterialOpacity(PixelMaterialInputs);
#endif
// Since the Convert-To-Decal node forces parameter blending for the entire Substrate tree, the BSDF we are interested in will be in 0.
const FSubstrateDBuffer DBuffer = DecalCommonOutput(Out, SubstrateHeader, SubstrateHeader.SubstrateTree.BSDFs[0], 1.0f /*CoverageWeight*/, CoverageOverBackground);
Coverage = DBuffer.Coverage;
}
const float Opacity = Coverage;
#endif // MOBILE_SUBSTRATE_USES_BLENDABLE_GBUFFER
#else // SUBSTRATE_ENABLED
float3 Color = GetMaterialEmissive(PixelMaterialInputs);
float Opacity = GetMaterialOpacity(PixelMaterialInputs);
FGBufferData GBufferData = (FGBufferData)0;
GBufferData.WorldNormal = MaterialParameters.WorldNormal;
GBufferData.BaseColor = GetMaterialBaseColor(PixelMaterialInputs);
GBufferData.Metallic = GetMaterialMetallic(PixelMaterialInputs);
GBufferData.Specular = GetMaterialSpecular(PixelMaterialInputs);
GBufferData.Roughness = GetMaterialRoughness(PixelMaterialInputs);
GBufferData.CustomData = 0;
GBufferData.IndirectIrradiance = 0;
GBufferData.PrecomputedShadowFactors = 1;
GBufferData.GBufferAO = GetMaterialAmbientOcclusion(PixelMaterialInputs);
GBufferData.ShadingModelID = SHADINGMODELID_DEFAULT_LIT;
GBufferData.SelectiveOutputMask = 0;
GBufferData.PerObjectGBufferData = 1;
GBufferData.DiffuseIndirectSampleOcclusion = 0;
GBufferData.Velocity = 0;
DecalCommonOutput(In, Out, Color, Opacity, GBufferData);
#endif // SUBSTRATE_ENABLED
#if MATERIAL_VIRTUALTEXTURE_FEEDBACK
FinalizeVirtualTextureFeedback(
MaterialParameters.VirtualTextureFeedback,
MaterialParameters.SvPosition,
View.VTFeedbackBuffer
);
#endif
}
void FPixelShaderInOut_MainPS(
FVertexFactoryInterpolantsVSToPS FactoryInterpolants,
#if NEED_MESH_DECAL_INTERPOLATORS
FMeshDecalInterpolants MeshDecalInterpolants,
#endif
inout FPixelShaderIn In,
inout FPixelShaderOut Out)
{
#if NEED_MESH_DECAL_INTERPOLATORS
FPixelShaderInOut_MainPS(FactoryInterpolants, MeshDecalInterpolants, In, Out, 0);
#else
FPixelShaderInOut_MainPS(FactoryInterpolants, In, Out, 0);
#endif
}
#define PIXELSHADEROUTPUT_MESHDECALPASS NEED_MESH_DECAL_INTERPOLATORS
#define PIXELSHADEROUTPUT_INTERPOLANTS 1
//#define PIXELSHADEROUTPUT_MRT0 (DECAL_RENDERTARGET_COUNT > 0)
//#define PIXELSHADEROUTPUT_MRT1 (DECAL_RENDERTARGET_COUNT > 1)
//#define PIXELSHADEROUTPUT_MRT2 (DECAL_RENDERTARGET_COUNT > 2)
//#define PIXELSHADEROUTPUT_MRT3 (DECAL_RENDERTARGET_COUNT > 3)
//#define PIXELSHADEROUTPUT_MRT4 (DECAL_RENDERTARGET_COUNT > 4)
// all PIXELSHADEROUTPUT_ and "void FPixelShaderInOut_MainPS()" need to be setup before this include
// this include generates the wrapper code to call MainPS()
#include "PixelShaderOutputCommon.ush"
#endif // PIXELSHADER