Files
UnrealEngineUWP/Engine/Source/Developer/MeshBuilder/Private/StaticMeshBuilder.cpp
Chris Gagnon 930e33cb48 Copying //UE4/Dev-Editor to Dev-Main (//UE4/Dev-Main) for 4.23 From CL 6837861
#rb none

[CL 6838042 by Chris Gagnon in Main branch]
2019-06-04 15:42:48 -04:00

631 lines
27 KiB
C++

// Copyright 1998-2019 Epic Games, Inc. All Rights Reserved.
#include "StaticMeshBuilder.h"
#include "Engine/StaticMesh.h"
#include "StaticMeshResources.h"
#include "PhysicsEngine/BodySetup.h"
#include "MeshDescription.h"
#include "MeshDescriptionOperations.h"
#include "MeshAttributes.h"
#include "MeshDescriptionHelper.h"
#include "BuildOptimizationHelper.h"
#include "Components.h"
#include "IMeshReductionManagerModule.h"
#include "MeshBuild.h"
#include "Modules/ModuleManager.h"
#include "IMeshReductionInterfaces.h"
DEFINE_LOG_CATEGORY(LogStaticMeshBuilder);
//////////////////////////////////////////////////////////////////////////
//Local functions definition
void BuildVertexBuffer(
UStaticMesh *StaticMesh
, int32 LodIndex
, const FMeshDescription& MeshDescription
, FStaticMeshLODResources& StaticMeshLOD
, const FMeshBuildSettings& LODBuildSettings
, TArray< uint32 >& IndexBuffer
, TArray<int32>& OutWedgeMap
, TArray<TArray<uint32> >& OutPerSectionIndices
, TArray< FStaticMeshBuildVertex >& StaticMeshBuildVertices
, const FOverlappingCorners& OverlappingCorners
, float VertexComparisonThreshold
, TArray<int32>& RemapVerts);
void BuildAllBufferOptimizations(struct FStaticMeshLODResources& StaticMeshLOD, const struct FMeshBuildSettings& LODBuildSettings, TArray< uint32 >& IndexBuffer, bool bNeeds32BitIndices, TArray< FStaticMeshBuildVertex >& StaticMeshBuildVertices);
//////////////////////////////////////////////////////////////////////////
FStaticMeshBuilder::FStaticMeshBuilder()
{
}
static bool UseNativeQuadraticReduction()
{
// Are we using our tool, or simplygon? The tool is only changed during editor restarts
IMeshReduction* ReductionModule = FModuleManager::Get().LoadModuleChecked<IMeshReductionManagerModule>("MeshReductionInterface").GetStaticMeshReductionInterface();
FString VersionString = ReductionModule->GetVersionString();
TArray<FString> SplitVersionString;
VersionString.ParseIntoArray(SplitVersionString, TEXT("_"), true);
bool bUseQuadricSimplier = SplitVersionString[0].Equals("QuadricMeshReduction");
return bUseQuadricSimplier;
}
bool FStaticMeshBuilder::Build(FStaticMeshRenderData& StaticMeshRenderData, UStaticMesh* StaticMesh, const FStaticMeshLODGroup& LODGroup)
{
// The tool can only been switch by restarting the editor
static bool bIsThirdPartyReductiontool = !UseNativeQuadraticReduction();
if (!StaticMesh->IsMeshDescriptionValid(0))
{
//Warn the user that there is no mesh description data
UE_LOG(LogStaticMeshBuilder, Error, TEXT("Cannot find a valid mesh description to build the asset."));
return false;
}
if (StaticMeshRenderData.LODResources.Num() > 0)
{
//At this point the render data is suppose to be empty
UE_LOG(LogStaticMeshBuilder, Error, TEXT("Cannot build static mesh render data twice [%s]."), *StaticMesh->GetFullName());
//Crash in debug
checkSlow(StaticMeshRenderData.LODResources.Num() == 0);
return false;
}
StaticMeshRenderData.AllocateLODResources(StaticMesh->SourceModels.Num());
TArray<FMeshDescription> MeshDescriptions;
MeshDescriptions.SetNum(StaticMesh->SourceModels.Num());
const FMeshSectionInfoMap BeforeBuildSectionInfoMap = StaticMesh->SectionInfoMap;
const FMeshSectionInfoMap BeforeBuildOriginalSectionInfoMap = StaticMesh->OriginalSectionInfoMap;
for (int32 LodIndex = 0; LodIndex < StaticMesh->SourceModels.Num(); ++LodIndex)
{
float MaxDeviation = 0.0f;
FMeshBuildSettings& LODBuildSettings = StaticMesh->SourceModels[LodIndex].BuildSettings;
const FMeshDescription* OriginalMeshDescription = StaticMesh->GetMeshDescription(LodIndex);
FMeshDescriptionHelper MeshDescriptionHelper(&LODBuildSettings);
const FStaticMeshSourceModel& SrcModel = StaticMesh->SourceModels[LodIndex];
FMeshReductionSettings ReductionSettings = LODGroup.GetSettings(SrcModel.ReductionSettings, LodIndex);
//Make sure we do not reduce a non custom LOD by himself
const int32 BaseReduceLodIndex = FMath::Clamp<int32>(ReductionSettings.BaseLODModel, 0, OriginalMeshDescription == nullptr ? LodIndex - 1 : LodIndex);
// Use simplifier if a reduction in triangles or verts has been requested.
bool bUseReduction = StaticMesh->IsReductionActive(LodIndex);
if (OriginalMeshDescription != nullptr)
{
MeshDescriptionHelper.GetRenderMeshDescription(StaticMesh, *OriginalMeshDescription, MeshDescriptions[LodIndex]);
}
else
{
if (bUseReduction)
{
// Initialize an empty mesh description that the reduce will fill
UStaticMesh::RegisterMeshAttributes(MeshDescriptions[LodIndex]);
}
else
{
//Duplicate the lodindex 0 we have a 100% reduction which is like a duplicate
MeshDescriptions[LodIndex] = MeshDescriptions[BaseReduceLodIndex];
//Set the overlapping threshold
float ComparisonThreshold = StaticMesh->SourceModels[BaseReduceLodIndex].BuildSettings.bRemoveDegenerates ? THRESH_POINTS_ARE_SAME : 0.0f;
MeshDescriptionHelper.FindOverlappingCorners(MeshDescriptions[LodIndex], ComparisonThreshold);
if (LodIndex > 0)
{
//Make sure the SectionInfoMap is taken from the Base RawMesh
int32 SectionNumber = StaticMesh->OriginalSectionInfoMap.GetSectionNumber(BaseReduceLodIndex);
for (int32 SectionIndex = 0; SectionIndex < SectionNumber; ++SectionIndex)
{
//Keep the old data if its valid
bool bHasValidLODInfoMap = StaticMesh->SectionInfoMap.IsValidSection(LodIndex, SectionIndex);
//Section material index have to be remap with the ReductionSettings.BaseLODModel SectionInfoMap to create
//a valid new section info map for the reduced LOD.
if (!bHasValidLODInfoMap && StaticMesh->SectionInfoMap.IsValidSection(BaseReduceLodIndex, SectionIndex))
{
//Copy the BaseLODModel section info to the reduce LODIndex.
FMeshSectionInfo SectionInfo = StaticMesh->SectionInfoMap.Get(BaseReduceLodIndex, SectionIndex);
FMeshSectionInfo OriginalSectionInfo = StaticMesh->OriginalSectionInfoMap.Get(BaseReduceLodIndex, SectionIndex);
StaticMesh->SectionInfoMap.Set(LodIndex, SectionIndex, SectionInfo);
StaticMesh->OriginalSectionInfoMap.Set(LodIndex, SectionIndex, OriginalSectionInfo);
}
}
}
}
if (LodIndex > 0)
{
LODBuildSettings = StaticMesh->SourceModels[BaseReduceLodIndex].BuildSettings;
}
}
//Reduce LODs
if (bUseReduction)
{
float OverlappingThreshold = LODBuildSettings.bRemoveDegenerates ? THRESH_POINTS_ARE_SAME : 0.0f;
FOverlappingCorners OverlappingCorners;
FMeshDescriptionOperations::FindOverlappingCorners(OverlappingCorners, MeshDescriptions[BaseReduceLodIndex], OverlappingThreshold);
int32 OldSectionInfoMapCount = StaticMesh->SectionInfoMap.GetSectionNumber(LodIndex);
if (LodIndex == BaseReduceLodIndex)
{
//When using LOD 0, we use a copy of the mesh description since reduce do not support inline reducing
FMeshDescription BaseMeshDescription = MeshDescriptions[BaseReduceLodIndex];
MeshDescriptionHelper.ReduceLOD(BaseMeshDescription, MeshDescriptions[LodIndex], ReductionSettings, OverlappingCorners, MaxDeviation);
}
else
{
MeshDescriptionHelper.ReduceLOD(MeshDescriptions[BaseReduceLodIndex], MeshDescriptions[LodIndex], ReductionSettings, OverlappingCorners, MaxDeviation);
}
const TPolygonGroupAttributesRef<FName> PolygonGroupImportedMaterialSlotNames = MeshDescriptions[LodIndex].PolygonGroupAttributes().GetAttributesRef<FName>(MeshAttribute::PolygonGroup::ImportedMaterialSlotName);
const TPolygonGroupAttributesRef<FName> BasePolygonGroupImportedMaterialSlotNames = MeshDescriptions[BaseReduceLodIndex].PolygonGroupAttributes().GetAttributesRef<FName>(MeshAttribute::PolygonGroup::ImportedMaterialSlotName);
// Recompute adjacency information. Since we change the vertices when we reduce
MeshDescriptionHelper.FindOverlappingCorners(MeshDescriptions[LodIndex], OverlappingThreshold);
//Make sure the static mesh SectionInfoMap is up to date with the new reduce LOD
//We have to remap the material index with the ReductionSettings.BaseLODModel sectionInfoMap
//Set the new SectionInfoMap for this reduced LOD base on the ReductionSettings.BaseLODModel SectionInfoMap
TArray<int32> BaseUniqueMaterialIndexes;
//Find all unique Material in used order
for (const FPolygonGroupID& PolygonGroupID : MeshDescriptions[BaseReduceLodIndex].PolygonGroups().GetElementIDs())
{
int32 MaterialIndex = StaticMesh->GetMaterialIndexFromImportedMaterialSlotName(BasePolygonGroupImportedMaterialSlotNames[PolygonGroupID]);
if (MaterialIndex == INDEX_NONE)
{
MaterialIndex = PolygonGroupID.GetValue();
}
BaseUniqueMaterialIndexes.AddUnique(MaterialIndex);
}
TArray<int32> UniqueMaterialIndex;
//Find all unique Material in used order
for (const FPolygonGroupID& PolygonGroupID : MeshDescriptions[LodIndex].PolygonGroups().GetElementIDs())
{
int32 MaterialIndex = StaticMesh->GetMaterialIndexFromImportedMaterialSlotName(PolygonGroupImportedMaterialSlotNames[PolygonGroupID]);
if (MaterialIndex == INDEX_NONE)
{
MaterialIndex = PolygonGroupID.GetValue();
}
UniqueMaterialIndex.AddUnique(MaterialIndex);
}
//If the reduce did not output the same number of section use the base LOD sectionInfoMap
bool bIsOldMappingInvalid = OldSectionInfoMapCount != MeshDescriptions[LodIndex].PolygonGroups().Num();
bool bValidBaseSectionInfoMap = BeforeBuildSectionInfoMap.GetSectionNumber(BaseReduceLodIndex) > 0;
//All used material represent a different section
for (int32 SectionIndex = 0; SectionIndex < UniqueMaterialIndex.Num(); ++SectionIndex)
{
//Keep the old data
bool bHasValidLODInfoMap = !bIsOldMappingInvalid && BeforeBuildSectionInfoMap.IsValidSection(LodIndex, SectionIndex);
//Section material index have to be remap with the ReductionSettings.BaseLODModel SectionInfoMap to create
//a valid new section info map for the reduced LOD.
//Find the base LOD section using this material
if (!bHasValidLODInfoMap)
{
bool bSectionInfoSet = false;
if (bValidBaseSectionInfoMap)
{
for (int32 BaseSectionIndex = 0; BaseSectionIndex < BaseUniqueMaterialIndexes.Num(); ++BaseSectionIndex)
{
if (UniqueMaterialIndex[SectionIndex] == BaseUniqueMaterialIndexes[BaseSectionIndex])
{
//Copy the base sectionInfoMap
FMeshSectionInfo SectionInfo = BeforeBuildSectionInfoMap.Get(BaseReduceLodIndex, BaseSectionIndex);
FMeshSectionInfo OriginalSectionInfo = BeforeBuildOriginalSectionInfoMap.Get(BaseReduceLodIndex, BaseSectionIndex);
StaticMesh->SectionInfoMap.Set(LodIndex, SectionIndex, SectionInfo);
StaticMesh->OriginalSectionInfoMap.Set(LodIndex, BaseSectionIndex, OriginalSectionInfo);
bSectionInfoSet = true;
break;
}
}
}
if (!bSectionInfoSet)
{
//Just set the default section info in case we did not found any match with the Base Lod
FMeshSectionInfo SectionInfo;
SectionInfo.MaterialIndex = SectionIndex;
StaticMesh->SectionInfoMap.Set(LodIndex, SectionIndex, SectionInfo);
StaticMesh->OriginalSectionInfoMap.Set(LodIndex, SectionIndex, SectionInfo);
}
}
}
}
const FPolygonGroupArray& PolygonGroups = MeshDescriptions[LodIndex].PolygonGroups();
FStaticMeshLODResources& StaticMeshLOD = StaticMeshRenderData.LODResources[LodIndex];
StaticMeshLOD.MaxDeviation = MaxDeviation;
//discover degenerate triangle with this threshold
float VertexComparisonThreshold = LODBuildSettings.bRemoveDegenerates ? THRESH_POINTS_ARE_SAME : 0.0f;
//Build new vertex buffers
TArray< FStaticMeshBuildVertex > StaticMeshBuildVertices;
TArray< uint32 > IndexBuffer;
StaticMeshLOD.Sections.Empty(PolygonGroups.Num());
TArray<int32> RemapVerts; //Because we will remove MeshVertex that are redundant, we need a remap
//Render data Wedge map is only set for LOD 0???
TArray<int32> TempWedgeMap;
TArray<int32> &WedgeMap = (LodIndex == 0) ? StaticMeshRenderData.WedgeMap : TempWedgeMap;
//Prepare the PerSectionIndices array so we can optimize the index buffer for the GPU
TArray<TArray<uint32> > PerSectionIndices;
PerSectionIndices.AddDefaulted(MeshDescriptions[LodIndex].PolygonGroups().Num());
//Build the vertex and index buffer
BuildVertexBuffer(StaticMesh, LodIndex, MeshDescriptions[LodIndex], StaticMeshLOD, LODBuildSettings, IndexBuffer, WedgeMap, PerSectionIndices, StaticMeshBuildVertices, MeshDescriptionHelper.GetOverlappingCorners(), VertexComparisonThreshold, RemapVerts);
// Concatenate the per-section index buffers.
TArray<uint32> CombinedIndices;
bool bNeeds32BitIndices = false;
for (int32 SectionIndex = 0; SectionIndex < StaticMeshLOD.Sections.Num(); SectionIndex++)
{
FStaticMeshSection& Section = StaticMeshLOD.Sections[SectionIndex];
TArray<uint32> const& SectionIndices = PerSectionIndices[SectionIndex];
Section.FirstIndex = 0;
Section.NumTriangles = 0;
Section.MinVertexIndex = 0;
Section.MaxVertexIndex = 0;
if (SectionIndices.Num())
{
Section.FirstIndex = CombinedIndices.Num();
Section.NumTriangles = SectionIndices.Num() / 3;
CombinedIndices.AddUninitialized(SectionIndices.Num());
uint32* DestPtr = &CombinedIndices[Section.FirstIndex];
uint32 const* SrcPtr = SectionIndices.GetData();
Section.MinVertexIndex = *SrcPtr;
Section.MaxVertexIndex = *SrcPtr;
for (int32 Index = 0; Index < SectionIndices.Num(); Index++)
{
uint32 VertIndex = *SrcPtr++;
bNeeds32BitIndices |= (VertIndex > MAX_uint16);
Section.MinVertexIndex = FMath::Min<uint32>(VertIndex, Section.MinVertexIndex);
Section.MaxVertexIndex = FMath::Max<uint32>(VertIndex, Section.MaxVertexIndex);
*DestPtr++ = VertIndex;
}
}
}
const EIndexBufferStride::Type IndexBufferStride = bNeeds32BitIndices ? EIndexBufferStride::Force32Bit : EIndexBufferStride::Force16Bit;
StaticMeshLOD.IndexBuffer.SetIndices(CombinedIndices, IndexBufferStride);
BuildAllBufferOptimizations(StaticMeshLOD, LODBuildSettings, CombinedIndices, bNeeds32BitIndices, StaticMeshBuildVertices);
} //End of LOD for loop
// Calculate the bounding box.
FBox BoundingBox(ForceInit);
FPositionVertexBuffer& BasePositionVertexBuffer = StaticMeshRenderData.LODResources[0].VertexBuffers.PositionVertexBuffer;
for (uint32 VertexIndex = 0; VertexIndex < BasePositionVertexBuffer.GetNumVertices(); VertexIndex++)
{
BoundingBox += BasePositionVertexBuffer.VertexPosition(VertexIndex);
}
BoundingBox.GetCenterAndExtents(StaticMeshRenderData.Bounds.Origin, StaticMeshRenderData.Bounds.BoxExtent);
// Calculate the bounding sphere, using the center of the bounding box as the origin.
StaticMeshRenderData.Bounds.SphereRadius = 0.0f;
for (uint32 VertexIndex = 0; VertexIndex < BasePositionVertexBuffer.GetNumVertices(); VertexIndex++)
{
StaticMeshRenderData.Bounds.SphereRadius = FMath::Max(
(BasePositionVertexBuffer.VertexPosition(VertexIndex) - StaticMeshRenderData.Bounds.Origin).Size(),
StaticMeshRenderData.Bounds.SphereRadius
);
}
return true;
}
bool AreVerticesEqual(FStaticMeshBuildVertex const& A, FStaticMeshBuildVertex const& B, float ComparisonThreshold)
{
if ( !A.Position.Equals(B.Position, ComparisonThreshold)
|| !NormalsEqual(A.TangentX, B.TangentX)
|| !NormalsEqual(A.TangentY, B.TangentY)
|| !NormalsEqual(A.TangentZ, B.TangentZ)
|| A.Color != B.Color)
{
return false;
}
// UVs
for (int32 UVIndex = 0; UVIndex < MAX_STATIC_TEXCOORDS; UVIndex++)
{
if (!UVsEqual(A.UVs[UVIndex], B.UVs[UVIndex]))
{
return false;
}
}
return true;
}
void BuildVertexBuffer(
UStaticMesh *StaticMesh
, int32 LodIndex
, const FMeshDescription& MeshDescription
, FStaticMeshLODResources& StaticMeshLOD
, const FMeshBuildSettings& LODBuildSettings
, TArray< uint32 >& IndexBuffer
, TArray<int32>& OutWedgeMap
, TArray<TArray<uint32> >& OutPerSectionIndices
, TArray< FStaticMeshBuildVertex >& StaticMeshBuildVertices
, const FOverlappingCorners& OverlappingCorners
, float VertexComparisonThreshold
, TArray<int32>& RemapVerts)
{
const FVertexArray& Vertices = MeshDescription.Vertices();
const FVertexInstanceArray& VertexInstances = MeshDescription.VertexInstances();
const FPolygonGroupArray& PolygonGroupArray = MeshDescription.PolygonGroups();
const FPolygonArray& PolygonArray = MeshDescription.Polygons();
TArray<int32> RemapVertexInstanceID;
// set up vertex buffer elements
StaticMeshBuildVertices.Reserve(VertexInstances.GetArraySize());
bool bHasColor = false;
TPolygonGroupAttributesConstRef<FName> PolygonGroupImportedMaterialSlotNames = MeshDescription.PolygonGroupAttributes().GetAttributesRef<FName>(MeshAttribute::PolygonGroup::ImportedMaterialSlotName);
TVertexAttributesConstRef<FVector> VertexPositions = MeshDescription.VertexAttributes().GetAttributesRef<FVector>( MeshAttribute::Vertex::Position );
TVertexInstanceAttributesConstRef<FVector> VertexInstanceNormals = MeshDescription.VertexInstanceAttributes().GetAttributesRef<FVector>( MeshAttribute::VertexInstance::Normal );
TVertexInstanceAttributesConstRef<FVector> VertexInstanceTangents = MeshDescription.VertexInstanceAttributes().GetAttributesRef<FVector>( MeshAttribute::VertexInstance::Tangent );
TVertexInstanceAttributesConstRef<float> VertexInstanceBinormalSigns = MeshDescription.VertexInstanceAttributes().GetAttributesRef<float>( MeshAttribute::VertexInstance::BinormalSign );
TVertexInstanceAttributesConstRef<FVector4> VertexInstanceColors = MeshDescription.VertexInstanceAttributes().GetAttributesRef<FVector4>( MeshAttribute::VertexInstance::Color );
TVertexInstanceAttributesConstRef<FVector2D> VertexInstanceUVs = MeshDescription.VertexInstanceAttributes().GetAttributesRef<FVector2D>( MeshAttribute::VertexInstance::TextureCoordinate );
const uint32 NumTextureCoord = VertexInstanceUVs.GetNumIndices();
TMap<FPolygonGroupID, int32> PolygonGroupToSectionIndex;
for (const FPolygonGroupID PolygonGroupID : MeshDescription.PolygonGroups().GetElementIDs())
{
int32& SectionIndex = PolygonGroupToSectionIndex.FindOrAdd(PolygonGroupID);
SectionIndex = StaticMeshLOD.Sections.Add(FStaticMeshSection());
FStaticMeshSection& StaticMeshSection = StaticMeshLOD.Sections[SectionIndex];
StaticMeshSection.MaterialIndex = StaticMesh->GetMaterialIndexFromImportedMaterialSlotName(PolygonGroupImportedMaterialSlotNames[PolygonGroupID]);
if (StaticMeshSection.MaterialIndex == INDEX_NONE)
{
StaticMeshSection.MaterialIndex = PolygonGroupID.GetValue();
}
}
int32 ReserveIndicesCount = 0;
for (const FPolygonID& PolygonID : MeshDescription.Polygons().GetElementIDs())
{
const TArray<FMeshTriangle>& PolygonTriangles = MeshDescription.GetPolygonTriangles(PolygonID);
ReserveIndicesCount += PolygonTriangles.Num() * 3;
}
IndexBuffer.Reset(ReserveIndicesCount);
//Fill the remap array
RemapVerts.AddZeroed(ReserveIndicesCount);
for (int32& RemapIndex : RemapVerts)
{
RemapIndex = INDEX_NONE;
}
//Initialize the wedge map array tracking correspondence between wedge index and rendering vertex index
OutWedgeMap.Reset();
OutWedgeMap.AddZeroed(ReserveIndicesCount);
int32 WedgeIndex = 0;
for (const FPolygonID& PolygonID : MeshDescription.Polygons().GetElementIDs())
{
const FPolygonGroupID PolygonGroupID = MeshDescription.GetPolygonPolygonGroup(PolygonID);
const int32 SectionIndex = PolygonGroupToSectionIndex[PolygonGroupID];
TArray<uint32>& SectionIndices = OutPerSectionIndices[SectionIndex];
const TArray<FMeshTriangle>& PolygonTriangles = MeshDescription.GetPolygonTriangles(PolygonID);
uint32 MinIndex = TNumericLimits< uint32 >::Max();
uint32 MaxIndex = TNumericLimits< uint32 >::Min();
for (int32 TriangleIndex = 0; TriangleIndex < PolygonTriangles.Num(); ++TriangleIndex)
{
const FMeshTriangle& Triangle = PolygonTriangles[TriangleIndex];
FVector CornerPositions[3];
for (int32 TriVert = 0; TriVert < 3; ++TriVert)
{
const FVertexInstanceID VertexInstanceID = Triangle.GetVertexInstanceID(TriVert);
const FVertexID VertexID = MeshDescription.GetVertexInstanceVertex(VertexInstanceID);
CornerPositions[TriVert] = VertexPositions[VertexID];
}
FOverlappingThresholds OverlappingThresholds;
OverlappingThresholds.ThresholdPosition = VertexComparisonThreshold;
// Don't process degenerate triangles.
if (PointsEqual(CornerPositions[0], CornerPositions[1], OverlappingThresholds)
|| PointsEqual(CornerPositions[0], CornerPositions[2], OverlappingThresholds)
|| PointsEqual(CornerPositions[1], CornerPositions[2], OverlappingThresholds))
{
continue;
}
for (int32 TriVert = 0; TriVert < 3; ++TriVert, ++WedgeIndex)
{
const FVertexInstanceID VertexInstanceID = Triangle.GetVertexInstanceID(TriVert);
const int32 VertexInstanceValue = VertexInstanceID.GetValue();
const FVector& VertexPosition = CornerPositions[TriVert];
const FVector& VertexInstanceNormal = VertexInstanceNormals[VertexInstanceID];
const FVector& VertexInstanceTangent = VertexInstanceTangents[VertexInstanceID];
const float VertexInstanceBinormalSign = VertexInstanceBinormalSigns[VertexInstanceID];
const FVector4& VertexInstanceColor = VertexInstanceColors[VertexInstanceID];
const FLinearColor LinearColor(VertexInstanceColor);
if (LinearColor != FLinearColor::White)
{
bHasColor = true;
}
FStaticMeshBuildVertex StaticMeshVertex;
StaticMeshVertex.Position = VertexPosition * LODBuildSettings.BuildScale3D;
const FMatrix ScaleMatrix = FScaleMatrix(LODBuildSettings.BuildScale3D).Inverse().GetTransposed();
StaticMeshVertex.TangentX = ScaleMatrix.TransformVector(VertexInstanceTangent).GetSafeNormal();
StaticMeshVertex.TangentY = ScaleMatrix.TransformVector(FVector::CrossProduct(VertexInstanceNormal, VertexInstanceTangent).GetSafeNormal() * VertexInstanceBinormalSign).GetSafeNormal();
StaticMeshVertex.TangentZ = ScaleMatrix.TransformVector(VertexInstanceNormal).GetSafeNormal();
StaticMeshVertex.Color = LinearColor.ToFColor(true);
const uint32 MaxNumTexCoords = FMath::Min<int32>(MAX_MESH_TEXTURE_COORDS_MD, MAX_STATIC_TEXCOORDS);
for (uint32 UVIndex = 0; UVIndex < MaxNumTexCoords; ++UVIndex)
{
if(UVIndex < NumTextureCoord)
{
StaticMeshVertex.UVs[UVIndex] = VertexInstanceUVs.Get(VertexInstanceID, UVIndex);
}
else
{
StaticMeshVertex.UVs[UVIndex] = FVector2D(0.0f, 0.0f);
}
}
//Never add duplicated vertex instance
//Use WedgeIndex since OverlappingCorners has been built based on that
const TArray<int32>& DupVerts = OverlappingCorners.FindIfOverlapping(WedgeIndex);
int32 Index = INDEX_NONE;
for (int32 k = 0; k < DupVerts.Num(); k++)
{
if (DupVerts[k] >= WedgeIndex)
{
break;
}
int32 Location = RemapVerts.IsValidIndex(DupVerts[k]) ? RemapVerts[DupVerts[k]] : INDEX_NONE;
if (Location != INDEX_NONE && AreVerticesEqual(StaticMeshVertex, StaticMeshBuildVertices[Location], VertexComparisonThreshold))
{
Index = Location;
break;
}
}
if (Index == INDEX_NONE)
{
Index = StaticMeshBuildVertices.Add(StaticMeshVertex);
}
RemapVerts[WedgeIndex] = Index;
const uint32 RenderingVertexIndex = Index;
IndexBuffer.Add(RenderingVertexIndex);
OutWedgeMap[WedgeIndex] = RenderingVertexIndex;
SectionIndices.Add(RenderingVertexIndex);
}
}
}
//Optimize before setting the buffer
if (VertexInstances.GetArraySize() < 100000 * 3)
{
BuildOptimizationHelper::CacheOptimizeVertexAndIndexBuffer(StaticMeshBuildVertices, OutPerSectionIndices, OutWedgeMap);
//check(OutWedgeMap.Num() == MeshDescription->VertexInstances().Num());
}
StaticMeshLOD.VertexBuffers.StaticMeshVertexBuffer.SetUseHighPrecisionTangentBasis(LODBuildSettings.bUseHighPrecisionTangentBasis);
StaticMeshLOD.VertexBuffers.StaticMeshVertexBuffer.SetUseFullPrecisionUVs(LODBuildSettings.bUseFullPrecisionUVs);
StaticMeshLOD.VertexBuffers.StaticMeshVertexBuffer.Init(StaticMeshBuildVertices, NumTextureCoord);
StaticMeshLOD.VertexBuffers.PositionVertexBuffer.Init(StaticMeshBuildVertices);
StaticMeshLOD.VertexBuffers.ColorVertexBuffer.Init(StaticMeshBuildVertices);
}
void BuildAllBufferOptimizations(FStaticMeshLODResources& StaticMeshLOD, const FMeshBuildSettings& LODBuildSettings, TArray< uint32 >& IndexBuffer, bool bNeeds32BitIndices, TArray< FStaticMeshBuildVertex >& StaticMeshBuildVertices)
{
if (StaticMeshLOD.AdditionalIndexBuffers == nullptr)
{
StaticMeshLOD.AdditionalIndexBuffers = new FAdditionalStaticMeshIndexBuffers();
}
const EIndexBufferStride::Type IndexBufferStride = bNeeds32BitIndices ? EIndexBufferStride::Force32Bit : EIndexBufferStride::Force16Bit;
// Build the reversed index buffer.
if (LODBuildSettings.bBuildReversedIndexBuffer)
{
TArray<uint32> InversedIndices;
const int32 IndexCount = IndexBuffer.Num();
InversedIndices.AddUninitialized(IndexCount);
for (int32 SectionIndex = 0; SectionIndex < StaticMeshLOD.Sections.Num(); ++SectionIndex)
{
const FStaticMeshSection& SectionInfo = StaticMeshLOD.Sections[SectionIndex];
const int32 SectionIndexCount = SectionInfo.NumTriangles * 3;
for (int32 i = 0; i < SectionIndexCount; ++i)
{
InversedIndices[SectionInfo.FirstIndex + i] = IndexBuffer[SectionInfo.FirstIndex + SectionIndexCount - 1 - i];
}
}
StaticMeshLOD.AdditionalIndexBuffers->ReversedIndexBuffer.SetIndices(InversedIndices, IndexBufferStride);
}
// Build the depth-only index buffer.
TArray<uint32> DepthOnlyIndices;
{
BuildOptimizationHelper::BuildDepthOnlyIndexBuffer(
DepthOnlyIndices,
StaticMeshBuildVertices,
IndexBuffer,
StaticMeshLOD.Sections
);
if (DepthOnlyIndices.Num() < 50000 * 3)
{
BuildOptimizationThirdParty::CacheOptimizeIndexBuffer(DepthOnlyIndices);
}
StaticMeshLOD.DepthOnlyIndexBuffer.SetIndices(DepthOnlyIndices, IndexBufferStride);
}
// Build the inversed depth only index buffer.
if (LODBuildSettings.bBuildReversedIndexBuffer)
{
TArray<uint32> ReversedDepthOnlyIndices;
const int32 IndexCount = DepthOnlyIndices.Num();
ReversedDepthOnlyIndices.AddUninitialized(IndexCount);
for (int32 i = 0; i < IndexCount; ++i)
{
ReversedDepthOnlyIndices[i] = DepthOnlyIndices[IndexCount - 1 - i];
}
StaticMeshLOD.AdditionalIndexBuffers->ReversedDepthOnlyIndexBuffer.SetIndices(ReversedDepthOnlyIndices, IndexBufferStride);
}
// Build a list of wireframe edges in the static mesh.
{
TArray<BuildOptimizationHelper::FMeshEdge> Edges;
TArray<uint32> WireframeIndices;
BuildOptimizationHelper::FStaticMeshEdgeBuilder(IndexBuffer, StaticMeshBuildVertices, Edges).FindEdges();
WireframeIndices.Empty(2 * Edges.Num());
for (int32 EdgeIndex = 0; EdgeIndex < Edges.Num(); EdgeIndex++)
{
BuildOptimizationHelper::FMeshEdge& Edge = Edges[EdgeIndex];
WireframeIndices.Add(Edge.Vertices[0]);
WireframeIndices.Add(Edge.Vertices[1]);
}
StaticMeshLOD.AdditionalIndexBuffers->WireframeIndexBuffer.SetIndices(WireframeIndices, IndexBufferStride);
}
// Build the adjacency index buffer used for tessellation.
if (LODBuildSettings.bBuildAdjacencyBuffer)
{
TArray<uint32> AdjacencyIndices;
BuildOptimizationThirdParty::NvTriStripHelper::BuildStaticAdjacencyIndexBuffer(
StaticMeshLOD.VertexBuffers.PositionVertexBuffer,
StaticMeshLOD.VertexBuffers.StaticMeshVertexBuffer,
IndexBuffer,
AdjacencyIndices
);
StaticMeshLOD.AdditionalIndexBuffers->AdjacencyIndexBuffer.SetIndices(AdjacencyIndices, IndexBufferStride);
}
}