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

247 lines
9.7 KiB
C++

// Copyright Epic Games, Inc. All Rights Reserved.
#include "ThumbnailRendering/TextureThumbnailRenderer.h"
#include "CanvasItem.h"
#include "Engine/Canvas.h"
#include "Engine/Engine.h"
#include "Engine/Texture.h"
#include "Engine/Texture2D.h"
#include "Engine/TextureLightProfile.h"
#include "ThumbnailRendering/ThumbnailManager.h"
#include "EngineGlobals.h"
#include "Engine/TextureCube.h"
#include "Engine/Texture2DArray.h"
#include "Engine/TextureCubeArray.h"
#include "Texture2DPreview.h"
#include "Engine/TextureRenderTargetCube.h"
#include "CubemapUnwrapUtils.h"
#include "CanvasItem.h"
#include "CanvasTypes.h"
#include "TextureResource.h"
UTextureThumbnailRenderer::UTextureThumbnailRenderer(const FObjectInitializer& ObjectInitializer)
: Super(ObjectInitializer)
{
}
void UTextureThumbnailRenderer::GetThumbnailSize(UObject* Object, float Zoom, uint32& OutWidth, uint32& OutHeight) const
{
UTexture* Texture = Cast<UTexture>(Object);
UTextureLightProfile* TextureLightProfile = Cast<UTextureLightProfile>(Object);
if (TextureLightProfile)
{
// otherwise a 1D texture would result in a very boring thumbnail
OutWidth = 192;
OutHeight = 192;
return;
}
if (Texture != nullptr)
{
UTexture2D* Texture2D = Cast<UTexture2D>(Texture);
FSharedImageConstRef CpuCopy;
if (Texture2D)
{
CpuCopy = Texture2D->GetCPUCopy();
}
if (CpuCopy.IsValid())
{
OutWidth = FMath::TruncToInt(Zoom * (float)CpuCopy->GetWidth());
OutHeight = FMath::TruncToInt(Zoom * (float)CpuCopy->GetHeight());
}
else
{
OutWidth = FMath::TruncToInt(Zoom * (float)Texture->GetSurfaceWidth());
OutHeight = FMath::TruncToInt(Zoom * (float)Texture->GetSurfaceHeight());
}
}
else
{
OutWidth = OutHeight = 0;
}
}
void UTextureThumbnailRenderer::Draw(UObject* Object, int32 X, int32 Y, uint32 Width, uint32 Height, FRenderTarget*, FCanvas* Canvas, bool bAdditionalViewFamily)
{
UTexture* Texture = Cast<UTexture>(Object);
if (Texture != nullptr && Texture->GetResource() != nullptr)
{
UTexture2D* Texture2D = Cast<UTexture2D>(Texture);
UTexture* CpuCopyTexture = nullptr;
if (Texture2D)
{
CpuCopyTexture = Texture2D->GetCPUCopyTexture();
}
// behavior here should match FTextureEditorViewportClient as much as possible
if (CpuCopyTexture == nullptr)
{
// Take the alpha channel into account for textures that have one.
// This provides a much better preview than just showing RGB,
// Because the RGB content in areas with an alpha of 0 is often garbage that will not be seen in normal conditions.
// Non-UI textures often have uncorrelated data in the alpha channel (like a skin mask, specular power, etc) so we only preview UI textures this way.
// @todo : this logic depending on LODGroup to decide whether alpha thumbnails should blend is very odd and unexpected for the user. Consider changing.
const bool bUseTranslucentBlend = Texture2D && Texture2D->HasAlphaChannel() && ((Texture2D->LODGroup == TEXTUREGROUP_UI) || (Texture2D->LODGroup == TEXTUREGROUP_Pixels2D));
UTextureCube* TextureCube = Cast<UTextureCube>(Texture);
UTexture2DArray* Texture2DArray = Cast<UTexture2DArray>(Texture);
UTextureCubeArray* TextureCubeArray = Cast<UTextureCubeArray>(Texture);
UTextureRenderTargetCube* RTTextureCube = Cast<UTextureRenderTargetCube>(Texture);
UTextureLightProfile* TextureLightProfile = Cast<UTextureLightProfile>(Texture);
const bool bIsVirtualTexture = Texture->IsCurrentlyVirtualTextured();
TRefCountPtr<FBatchedElementParameters> BatchedElementParameters;
// BatchedElementParameters is released by the render thread when it was rendered
if(TextureCube || TextureCubeArray || RTTextureCube)
{
// show LongLat Unwrap
float MipLevel = -1.f;
float SliceIndex = -1.f;
bool bShowLongLatUnwrap = true;
BatchedElementParameters = new FMipLevelBatchedElementParameters(MipLevel, SliceIndex, TextureCubeArray != nullptr, FMatrix44f::Identity, bShowLongLatUnwrap, false, false);
// If the thumbnail is square then make it 2:1 for cubes.
if(Width == Height)
{
Height = Width / 2;
Y += Height / 2;
}
}
else if (TextureLightProfile)
{
BatchedElementParameters = new FIESLightProfileBatchedElementParameters(TextureLightProfile->Brightness);
}
else if (Texture2D || Texture2DArray)
{
bool bIsNormalMap = Texture->IsNormalMap();
bool bIsSingleChannel = Texture->CompressionSettings == TC_Grayscale || Texture->CompressionSettings == TC_Alpha;
bool bSingleVTPhysicalSpace = Texture2D && Texture2D->IsVirtualTexturedWithSinglePhysicalSpace();
float MipLevel = -1.f;
float LayerIndex = 0;
float SliceIndex = -1.f;
bool bIsTextureArray = (Texture2DArray != nullptr);
bool bUsePointSampling = false;
// if you correctly tell FBatchedElementTexture2DPreviewParameters that the texture is a VT
// then you only get a solid color thumbnail for the initial render
// but if it is refreshes or the VT is examined, the thumbnail will become correct
//bool bSampleAsVirtualTexture = bIsVirtualTexture;
// if you just always lie and say you are not a VT, you get a good thumbnail :
bool bSampleAsVirtualTexture = false;
BatchedElementParameters = new FBatchedElementTexture2DPreviewParameters(MipLevel, LayerIndex, SliceIndex, bIsNormalMap, bIsSingleChannel, bSingleVTPhysicalSpace, bSampleAsVirtualTexture, bIsTextureArray, bUsePointSampling);
}
else
{
// BatchedElementParameters is not set
// default Canvas will be used, which just shows the texture
// (what shader does this use??)
// some UTexture types can hit this
// UTextureRenderTarget
// ?? maybe get rid of this and just always use the Texture2D branch above
}
if (bUseTranslucentBlend)
{
// If using alpha, draw a checkerboard underneath first.
const int32 CheckerDensity = 8;
auto Checker = UThumbnailManager::Get().CheckerboardTexture;
Canvas->DrawTile(
0.0f, 0.0f, Width, Height, // Dimensions
0.0f, 0.0f, CheckerDensity, CheckerDensity, // UVs
FLinearColor::White, Checker->GetResource()); // Tint & Texture
}
// Use A canvas tile item to draw
FCanvasTileItem CanvasTile( FVector2D( X, Y ), Texture->GetResource(), FVector2D( Width,Height ), FLinearColor::White );
if ( BatchedElementParameters == nullptr )
{
// old style BatchedElementParameters == null wants you to use "Translucent" :
CanvasTile.BlendMode = bUseTranslucentBlend ? SE_BLEND_Translucent : SE_BLEND_Opaque;
}
else
{
// matches the behavior of FTextureEditorViewportClient::Draw and FTextureEditorToolkit::GetColourChannelBlendMode
// I think it may be a bug in BatchedElement that SE_BLEND_Translucent doesn't work here (failing to set up TextureComponentReplicate?)
CanvasTile.BlendMode = bUseTranslucentBlend ? (ESimpleElementBlendMode)(SE_BLEND_RGBA_MASK_START+0xF) : SE_BLEND_Opaque;
}
CanvasTile.BatchedElementParameters = BatchedElementParameters;
if (bIsVirtualTexture && Texture->Source.GetNumBlocks() > 1)
{
// Adjust UVs to display entire UDIM range, acounting for UE inverted V-axis
// We're not actually rendering a VT here, but the editor-only texture we're using is still using the UDIM tile layout
// So we use inverted Y-axis, but then normalize back to [0,1)
const FIntPoint BlockSize = Texture->Source.GetSizeInBlocks();
const float RcpBlockSizeY = 1.0f / (float)BlockSize.Y;
CanvasTile.UV0.Y = (1.0f - (float)BlockSize.Y) * RcpBlockSizeY;
CanvasTile.UV1.Y = RcpBlockSizeY;
}
CanvasTile.Draw( Canvas );
if (TextureLightProfile)
{
float Brightness = TextureLightProfile->Brightness;
// Brightness in Lumens
FText BrightnessText = FText::AsNumber( Brightness );
FCanvasTextItem TextItem( FVector2D( 5.0f, 5.0f ), BrightnessText, GEngine->GetLargeFont(), FLinearColor::White );
TextItem.EnableShadow(FLinearColor::Black);
TextItem.Scale = FVector2D(Width / 128.0f, Height / 128.0f);
TextItem.Draw(Canvas);
}
if (bIsVirtualTexture)
{
auto VTChars = TEXT("VT");
int32 VTWidth = 0;
int32 VTHeight = 0;
StringSize(GEngine->GetLargeFont(), VTWidth, VTHeight, VTChars);
float PaddingX = Width / 128.0f;
float PaddingY = Height / 128.0f;
float ScaleX = Width / 64.0f; //Text is 1/64'th of the size of the thumbnails
float ScaleY = Height / 64.0f;
// VT overlay
FCanvasTextItem TextItem(FVector2D(Width - PaddingX - VTWidth * ScaleX, Height - PaddingY - VTHeight * ScaleY), FText::FromString(VTChars), GEngine->GetLargeFont(), FLinearColor::White);
TextItem.EnableShadow(FLinearColor::Black);
TextItem.Scale = FVector2D(ScaleX, ScaleY);
TextItem.Draw(Canvas);
}
}
else
{
// Render a tile using a transient texture that holds the cpu copy.
Canvas->DrawTile(
0.0f, 0.0f, Width, Height, // Dimensions
0.0f, 0.0f, 1.0f, 1.0f, // UVs
FLinearColor::White, CpuCopyTexture->GetResource()); // Tint & Texture
const TCHAR* Chars = TEXT("CPU");
int32 TextWidth = 0;
int32 TextHeight = 0;
StringSize(GEngine->GetLargeFont(), TextWidth, TextHeight, Chars);
float PaddingX = Width / 128.0f;
float PaddingY = Height / 128.0f;
float ScaleX = Width / 64.0f; //Text is 1/64'th of the size of the thumbnails
float ScaleY = Height / 64.0f;
// overlay
FCanvasTextItem TextItem(FVector2D(Width - PaddingX - TextWidth * ScaleX, Height - PaddingY - TextHeight * ScaleY), FText::FromString(Chars), GEngine->GetLargeFont(), FLinearColor::White);
TextItem.EnableShadow(FLinearColor::Black);
TextItem.Scale = FVector2D(ScaleX, ScaleY);
TextItem.Draw(Canvas);
}
}
}
bool UTextureThumbnailRenderer::CanVisualizeAsset(UObject* Object)
{
UTexture* Texture = Cast<UTexture>(Object);
return (Texture && !Texture->IsCompiling());
}