Files
UnrealEngine/Engine/Source/Editor/MeshPaint/Private/IMeshPaintGeometryAdapter.cpp
2025-05-18 13:04:45 +08:00

97 lines
4.2 KiB
C++

// Copyright Epic Games, Inc. All Rights Reserved.
#include "IMeshPaintGeometryAdapter.h"
#include "Engine/World.h"
#include "Components/MeshComponent.h"
#include "MeshPaintTypes.h"
#include "Materials/MaterialExpressionTextureBase.h"
#include "Materials/MaterialExpressionTextureSample.h"
#include "Materials/Material.h"
#include "Materials/MaterialExpressionTextureCoordinate.h"
#include "Materials/MaterialExpressionTextureSampleParameter.h"
#include "MaterialShared.h"
#include "TexturePaintHelpers.h"
//////////////////////////////////////////////////////////////////////////
// IMeshPaintGeometryAdapter
void IMeshPaintGeometryAdapter::DefaultApplyOrRemoveTextureOverride(UMeshComponent* InMeshComponent, UTexture* SourceTexture, UTexture* OverrideTexture)
{
const ERHIFeatureLevel::Type FeatureLevel = InMeshComponent->GetWorld()->GetFeatureLevel();
// Check all the materials on the mesh to see if the user texture is there
int32 MaterialIndex = 0;
UMaterialInterface* MaterialToCheck = InMeshComponent->GetMaterial(MaterialIndex);
while (MaterialToCheck != nullptr)
{
const bool bIsTextureUsed = DoesMaterialUseTexture(MaterialToCheck, SourceTexture);
if (bIsTextureUsed)
{
MaterialToCheck->OverrideTexture(SourceTexture, OverrideTexture, FeatureLevel);
}
++MaterialIndex;
MaterialToCheck = InMeshComponent->GetMaterial(MaterialIndex);
}
}
void IMeshPaintGeometryAdapter::DefaultQueryPaintableTextures(int32 MaterialIndex, const UMeshComponent* MeshComponent, int32& OutDefaultIndex, TArray<struct FPaintableTexture>& InOutTextureList)
{
OutDefaultIndex = INDEX_NONE;
// We already know the material we are painting on, take it off the static mesh component
UMaterialInterface* Material = MeshComponent->GetMaterial(MaterialIndex);
if (Material != NULL)
{
FPaintableTexture PaintableTexture;
// Find all the unique textures used in the top material level of the selected actor materials
// Only grab the textures from the top level of samples
for (UMaterialExpression* Expression : Material->GetMaterial()->GetExpressions())
{
UMaterialExpressionTextureBase* TextureBase = Cast<UMaterialExpressionTextureBase>(Expression);
if (TextureBase != NULL &&
TextureBase->Texture != NULL &&
!TextureBase->Texture->IsNormalMap() &&
!TextureBase->Texture->VirtualTextureStreaming &&
!TextureBase->Texture->HasHDRSource() && // Currently HDR textures are not supported to paint on.
(TextureBase->Texture->Source.GetBytesPerPixel() <= TexturePaintHelpers::GetMaxSupportedBytesPerPixelForPainting())) // Textures' sources must fit in FColor struct to be supported.
{
// Default UV channel to index 0.
PaintableTexture = FPaintableTexture(TextureBase->Texture, 0);
// Texture Samples can have UV's specified, check the first node for whether it has a custom UV channel set.
// We only check the first as the Mesh paint mode does not support painting with UV's modified in the shader.
UMaterialExpressionTextureSample* TextureSample = Cast<UMaterialExpressionTextureSample>(Expression);
if (TextureSample != NULL)
{
UMaterialExpressionTextureCoordinate* TextureCoords = Cast<UMaterialExpressionTextureCoordinate>(TextureSample->Coordinates.Expression);
if (TextureCoords != NULL)
{
// Store the uv channel, this is set when the texture is selected.
PaintableTexture.UVChannelIndex = TextureCoords->CoordinateIndex;
}
// Handle texture parameter expressions
UMaterialExpressionTextureSampleParameter* TextureSampleParameter = Cast<UMaterialExpressionTextureSampleParameter>(TextureSample);
if (TextureSampleParameter != NULL)
{
// Grab the overridden texture if it exists.
Material->GetTextureParameterValue(TextureSampleParameter->ParameterName, PaintableTexture.Texture);
}
}
// note that the same texture will be added again if its UV channel differs.
int32 TextureIndex = InOutTextureList.AddUnique(PaintableTexture);
// cache the first default index, if there is no previous info this will be used as the selected texture
if ((OutDefaultIndex == INDEX_NONE) && TextureBase->IsDefaultMeshpaintTexture)
{
OutDefaultIndex = TextureIndex;
}
}
}
}
}