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UnrealEngineUWP/Engine/Source/Developer/TextureCompressor/Private/TextureCompressorModule.cpp
martins mozeiko b7ce1b7247 Adds option to use separable filter for generating mips. 
This allows faster texture cooking, but introduces slight changes to newly computed pixel values.
Quality of texture mips stays the same, but values are different due to different order of floating-point operations.
To keep patch sizes small, use old same code as before for generating mips for existing textures - will use new filter only for saved textures.
Currently this setting is disabled for new textures by default. See comment in Texture.cpp how to enable it.

#rb charles.bloom fabian.giesen
#preflight 624c9d9a8d1db441a9137202

[CL 19630307 by martins mozeiko in ue5-main branch]
2022-04-05 16:10:56 -04:00

3512 lines
117 KiB
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// Copyright Epic Games, Inc. All Rights Reserved.
#include "TextureCompressorModule.h"
#include "Math/RandomStream.h"
#include "Containers/IndirectArray.h"
#include "Stats/Stats.h"
#include "Async/AsyncWork.h"
#include "Async/ParallelFor.h"
#include "Modules/ModuleManager.h"
#include "Engine/TextureDefines.h"
#include "TextureFormatManager.h"
#include "Interfaces/ITextureFormat.h"
#include "Misc/Paths.h"
#include "Tasks/Task.h"
#include "ImageCore.h"
#include <cmath>
#if PLATFORM_WINDOWS
#include "Windows/WindowsHWrapper.h"
#endif
DEFINE_LOG_CATEGORY_STATIC(LogTextureCompressor, Log, All);
/*------------------------------------------------------------------------------
Mip-Map Generation
------------------------------------------------------------------------------*/
// NOTE: mip gen wrap/clamp does NOT correspond to Texture Address Wrap/Clamp setting !!
// it comes from bPreserveBorder !
enum EMipGenAddressMode
{
MGTAM_Wrap,
MGTAM_Clamp,
MGTAM_BorderBlack,
};
/**
* 2D view into one slice of an image.
*/
struct FImageView2D
{
/** Pointer to colors in the slice. */
FLinearColor* SliceColors;
/** Width of the slice. */
int32 SizeX;
/** Height of the slice. */
int32 SizeY;
FImageView2D() : SliceColors(nullptr), SizeX(0), SizeY(0) {}
/** Initialization constructor. */
FImageView2D(FImage& Image, int32 SliceIndex)
{
SizeX = Image.SizeX;
SizeY = Image.SizeY;
check( SliceIndex < Image.NumSlices );
SliceColors = (&Image.AsRGBA32F()[0]) + SliceIndex * SizeY * SizeX;
}
/** Access a single texel. */
FLinearColor& Access(int32 X, int32 Y)
{
return SliceColors[X + Y * SizeX];
}
/** Const access to a single texel. */
const FLinearColor& Access(int32 X, int32 Y) const
{
return SliceColors[X + Y * SizeX];
}
bool IsValid() const { return SliceColors != nullptr; }
static const FImageView2D ConstructConst(const FImage& Image, int32 SliceIndex)
{
return FImageView2D(const_cast<FImage&>(Image), SliceIndex);
}
};
// 2D sample lookup with input conversion
// requires SourceImageData.SizeX and SourceImageData.SizeY to be power of two
template <EMipGenAddressMode AddressMode>
static const FLinearColor& LookupSourceMip(const FImageView2D& SourceImageData, int32 X, int32 Y)
{
if(AddressMode == MGTAM_Wrap)
{
// wrap
// ! requires pow2 sizes
checkSlow( FMath::IsPowerOfTwo(SourceImageData.SizeX) );
checkSlow( FMath::IsPowerOfTwo(SourceImageData.SizeY) );
X = (int32)((uint32)X) & (SourceImageData.SizeX - 1);
Y = (int32)((uint32)Y) & (SourceImageData.SizeY - 1);
}
else if(AddressMode == MGTAM_Clamp)
{
// clamp
X = FMath::Clamp(X, 0, SourceImageData.SizeX - 1);
Y = FMath::Clamp(Y, 0, SourceImageData.SizeY - 1);
}
else if(AddressMode == MGTAM_BorderBlack)
{
// border color 0
if((uint32)X >= (uint32)SourceImageData.SizeX
|| (uint32)Y >= (uint32)SourceImageData.SizeY)
{
static FLinearColor Black(0, 0, 0, 0);
return Black;
}
}
else
{
check(0);
}
return SourceImageData.Access(X, Y);
}
// Same functionality as above, but for 1D lookup with explicit size
template <EMipGenAddressMode AddressMode>
static const FLinearColor& LookupSourceMip(const FLinearColor* Data, int32 Size, int32 X)
{
if (AddressMode == MGTAM_Wrap)
{
// wrap
// ! requires pow2 sizes
checkSlow( FMath::IsPowerOfTwo(Size) );
X = (int32)((uint32)X) & (Size - 1);
}
else if (AddressMode == MGTAM_Clamp)
{
// clamp
X = FMath::Clamp(X, 0, Size - 1);
}
else if (AddressMode == MGTAM_BorderBlack)
{
// border color 0
if ((uint32)X >= (uint32)Size)
{
static FLinearColor Black(0, 0, 0, 0);
return Black;
}
}
else
{
check(0);
}
return Data[X];
}
// Kernel class for image filtering operations like image downsampling
// at max MaxKernelExtend x MaxKernelExtend
class FImageKernel2D
{
public:
FImageKernel2D() :FilterTableSize(0)
{
}
// @param TableSize1D 2 for 2x2, 4 for 4x4, 6 for 6x6, 8 for 8x8
// @param SharpenFactor can be negative to blur
// generate normalized 2D Kernel with sharpening
void BuildSeparatableGaussWithSharpen(uint32 TableSize1D, float SharpenFactor = 0.0f)
{
if(TableSize1D > MaxKernelExtend)
{
TableSize1D = MaxKernelExtend;
}
float* Table1D = KernelWeights1D;
float NegativeTable1D[MaxKernelExtend];
FilterTableSize = TableSize1D;
if(TableSize1D == 2)
{
// 2x2 kernel: simple average
// SharpenFactor is ignored
// this is TMGS_SimpleAverage
Table1D[0] = Table1D[1] = 0.5f;
KernelWeights[0] = KernelWeights[1] = KernelWeights[2] = KernelWeights[3] = 0.25f;
return;
}
else if(SharpenFactor < 0.0f)
{
// blur only
// this is TMGS_Blur
// TMGS_Blur will always give us TableSize > 2
check( TableSize1D > 2 );
BuildGaussian1D(Table1D, TableSize1D, 1.0f, -SharpenFactor);
BuildFilterTable2DFrom1D(KernelWeights, Table1D, TableSize1D);
return;
}
else if(TableSize1D == 4)
{
// 4x4 kernel with sharpen or blur: can alias a bit
// this is not used by standard TMGS_ mip options
// one thing that can get you in here is GenerateTopMip
// because it takes the standard 8 size and does /2
BuildFilterTable1DBase(Table1D, TableSize1D, 1.0f + SharpenFactor);
BuildFilterTable1DBase(NegativeTable1D, TableSize1D, -SharpenFactor);
BlurFilterTable1D(NegativeTable1D, TableSize1D, 1);
}
else if(TableSize1D == 6)
{
// 6x6 kernel with sharpen or blur: still can alias
// this is not used by standard TMGS_ mip options
BuildFilterTable1DBase(Table1D, TableSize1D, 1.0f + SharpenFactor);
BuildFilterTable1DBase(NegativeTable1D, TableSize1D, -SharpenFactor);
BlurFilterTable1D(NegativeTable1D, TableSize1D, 2);
}
else if(TableSize1D == 8)
{
//8x8 kernel with sharpen
// these are the TMGS_Sharpen filters
// * 2 to get similar appearance as for TableSize 6
SharpenFactor = SharpenFactor * 2.0f;
BuildFilterTable1DBase(Table1D, TableSize1D, 1.0f + SharpenFactor);
// positive lobe is blurred a bit for better quality
BlurFilterTable1D(Table1D, TableSize1D, 1);
BuildFilterTable1DBase(NegativeTable1D, TableSize1D, -SharpenFactor);
BlurFilterTable1D(NegativeTable1D, TableSize1D, 3);
}
else
{
// not yet supported
check(0);
}
AddFilterTable1D(Table1D, NegativeTable1D, TableSize1D);
BuildFilterTable2DFrom1D(KernelWeights, Table1D, TableSize1D);
}
inline uint32 GetFilterTableSize() const
{
return FilterTableSize;
}
inline float Get1D(uint32 X) const
{
checkSlow(X < FilterTableSize);
return KernelWeights1D[X];
}
inline float GetAt(uint32 X, uint32 Y) const
{
checkSlow(X < FilterTableSize);
checkSlow(Y < FilterTableSize);
return KernelWeights[X + Y * FilterTableSize];
}
private:
inline static float NormalDistribution(float X, float Variance)
{
const float StandardDeviation = FMath::Sqrt(Variance);
return FMath::Exp(-FMath::Square(X) / (2.0f * Variance)) / (StandardDeviation * FMath::Sqrt(2.0f * (float)PI));
}
// support even and non even sized filters
static void BuildGaussian1D(float *InOutTable, uint32 TableSize, float Sum, float Variance)
{
float Center = TableSize * 0.5f - 0.5f;
float CurrentSum = 0;
for(uint32 i = 0; i < TableSize; ++i)
{
float Actual = NormalDistribution(i - Center, Variance);
InOutTable[i] = Actual;
CurrentSum += Actual;
}
// Normalize
float InvSum = Sum / CurrentSum;
for(uint32 i = 0; i < TableSize; ++i)
{
InOutTable[i] *= InvSum;
}
}
//
static void BuildFilterTable1DBase(float *InOutTable, uint32 TableSize, float Sum )
{
// we require a even sized filter
check(TableSize % 2 == 0);
float Inner = 0.5f * Sum;
uint32 Center = TableSize / 2;
for(uint32 x = 0; x < TableSize; ++x)
{
if(x == Center || x == Center - 1)
{
// center elements
InOutTable[x] = Inner;
}
else
{
// outer elements
InOutTable[x] = 0.0f;
}
}
}
// InOutTable += InTable
static void AddFilterTable1D( float *InOutTable, float *InTable, uint32 TableSize )
{
for(uint32 x = 0; x < TableSize; ++x)
{
InOutTable[x] += InTable[x];
}
}
// @param Times 1:box, 2:triangle, 3:pow2, 4:pow3, ...
// can be optimized with double buffering but doesn't need to be fast
static void BlurFilterTable1D( float *InOutTable, uint32 TableSize, uint32 Times )
{
check(Times>0);
check(TableSize<32);
float Intermediate[32];
for(uint32 Pass = 0; Pass < Times; ++Pass)
{
for(uint32 x = 0; x < TableSize; ++x)
{
Intermediate[x] = InOutTable[x];
}
for(uint32 x = 0; x < TableSize; ++x)
{
float sum = Intermediate[x];
if(x)
{
sum += Intermediate[x-1];
}
if(x < TableSize - 1)
{
sum += Intermediate[x+1];
}
InOutTable[x] = sum / 3.0f;
}
}
}
static void BuildFilterTable2DFrom1D( float *OutTable2D, float *InTable1D, uint32 TableSize )
{
for(uint32 y = 0; y < TableSize; ++y)
{
for(uint32 x = 0; x < TableSize; ++x)
{
OutTable2D[x + y * TableSize] = InTable1D[y] * InTable1D[x];
}
}
}
// at max we support MaxKernelExtend x MaxKernelExtend kernels
const static uint32 MaxKernelExtend = 12;
// 0 if no kernel was setup yet
uint32 FilterTableSize;
// normalized, means the sum of it should be 1.0f
float KernelWeights[MaxKernelExtend * MaxKernelExtend];
float KernelWeights1D[MaxKernelExtend];
};
static float DetermineScaledThreshold(float Threshold, float Scale)
{
check(Threshold > 0.f && Scale > 0.f);
// Assuming Scale > 0 and Threshold > 0, find ScaledThreshold such that
// x * Scale >= Threshold
// is exactly equivalent to
// x >= ScaledThreshold.
//
// This is for a test that was originally written in the first form that we want to
// transform to the second form without changing results (which would in turn change
// texture cooks).
//
// In exact arithmetic, this is just ScaledThreshold = Threshold / Scale.
//
// In floating point, we need to consider rounding. Computed in floating point
// and assuming round-to-nearest (breaking ties towards even), we get
//
// RN(x * Scale) >= Threshold
//
// The smallest conceivable x that passes RN(x * Scale) >= Threshold is
// x = (Threshold - 0.5u) / Scale, landing exactly halfway with the rounding
// going up; this is slightly less than an exact Threshold/Scale.
//
// For regular floating point division, we get
// RN(Threshold / Scale)
// = (Threshold / Scale) * (1 + e), |e| < 0.5u (the inequality is strict for divisions)
//
// That gets us relatively close to the target value, but we have no guarantee that rounding
// on the division was in the direction we wanted. Just check whether our target inequality
// is satisfied and bump up or down to the next representable float as required.
float ScaledThreshold = Threshold / Scale;
float SteppedDown = std::nextafter(ScaledThreshold, 0.f);
// We want ScaledThreshold to be the smallest float such that
// ScaledThreshold * Scale >= Threshold
// meaning the next-smaller float below ScaledThreshold (which is SteppedDown)
// should not be >=Threshold.
if (SteppedDown * Scale >= Threshold)
{
// We were too large, go down by 1 ulp
ScaledThreshold = SteppedDown;
}
else if (ScaledThreshold * Scale < Threshold)
{
// We were too small, go up by 1 ulp
ScaledThreshold = std::nextafter(ScaledThreshold, 2.f * ScaledThreshold);
}
// We should now have the right threshold:
check(ScaledThreshold * Scale >= Threshold); // ScaledThreshold is large enough
check(std::nextafter(ScaledThreshold, 0.f) * Scale < Threshold); // next below is too small
return ScaledThreshold;
}
static FVector4f ComputeAlphaCoverage(const FVector4f Thresholds, const FVector4f Scales, const FImageView2D& SourceImageData)
{
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.ComputeAlphaCoverage);
FVector4f Coverage(0, 0, 0, 0);
int32 NumRowsEachJob;
int32 NumJobs = ImageParallelForComputeNumJobsForRows(NumRowsEachJob,SourceImageData.SizeX,SourceImageData.SizeY);
if ( Thresholds[0] == 0.f && Thresholds[1] == 0.f && Thresholds[2] == 0.f )
{
// common case that only channel 3 (A) is used for alpha coverage :
check( Thresholds[3] != 0.f );
const float ThresholdScaled = DetermineScaledThreshold(Thresholds[3] , Scales[3]);
int32 CommonResult = 0;
ParallelFor( TEXT("Texture.ComputeAlphaCoverage.PF"),NumJobs,1, [&](int32 Index)
{
int32 StartIndex = Index * NumRowsEachJob;
int32 EndIndex = FMath::Min(StartIndex + NumRowsEachJob, SourceImageData.SizeY);
int32 LocalCoverage = 0;
for (int32 y = StartIndex; y < EndIndex; ++y)
{
const FLinearColor * RowPixels = &SourceImageData.Access(0,y);
for (int32 x = 0; x < SourceImageData.SizeX; ++x)
{
LocalCoverage += (RowPixels[x].A >= ThresholdScaled);
}
}
FPlatformAtomics::InterlockedAdd(&CommonResult, LocalCoverage);
});
Coverage[3] = float(CommonResult) / float(SourceImageData.SizeX * SourceImageData.SizeY);
UE_LOG(LogTextureCompressor, VeryVerbose, TEXT("Thresholds = 000 %f Coverage = 000 %f"), \
Thresholds[3], Coverage[3] );
}
else
{
FVector4f ThresholdsScaled;
for (int32 i = 0; i < 4; ++i)
{
// Skip channel if Threshold is 0
if (Thresholds[i] == 0)
{
// stuff a value that we will always be less than
ThresholdsScaled[i] = FLT_MAX;
}
else
{
check( Scales[i] != 0.f );
ThresholdsScaled[i] = DetermineScaledThreshold( Thresholds[i] , Scales[i] );
}
}
int32 CommonResults[4] = { 0, 0, 0, 0 };
ParallelFor( TEXT("Texture.ComputeAlphaCoverage.PF"),NumJobs,1, [&](int32 Index)
{
int32 StartIndex = Index * NumRowsEachJob;
int32 EndIndex = FMath::Min(StartIndex + NumRowsEachJob, SourceImageData.SizeY);
int32 LocalCoverage[4] = { 0, 0, 0, 0 };
for (int32 y = StartIndex; y < EndIndex; ++y)
{
const FLinearColor * RowPixels = &SourceImageData.Access(0,y);
for (int32 x = 0; x < SourceImageData.SizeX; ++x)
{
const FLinearColor & PixelValue = RowPixels[x];
// Calculate coverage for each channel
for (int32 i = 0; i < 4; ++i)
{
LocalCoverage[i] += ( PixelValue.Component(i) >= ThresholdsScaled[i] );
}
}
}
for (int32 i = 0; i < 4; ++i)
{
FPlatformAtomics::InterlockedAdd(&CommonResults[i], LocalCoverage[i]);
}
});
for (int32 i = 0; i < 4; ++i)
{
Coverage[i] = float(CommonResults[i]) / float(SourceImageData.SizeX * SourceImageData.SizeY);
}
UE_LOG(LogTextureCompressor, VeryVerbose, TEXT("Thresholds = %f %f %f %f Coverage = %f %f %f %f"), \
Thresholds[0], Thresholds[1], Thresholds[2], Thresholds[3], \
Coverage[0], Coverage[1], Coverage[2], Coverage[3] );
}
return Coverage;
}
static FVector4f ComputeAlphaScale(const FVector4f Coverages, const FVector4f AlphaThresholds, const FImageView2D& SourceImageData)
{
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.ComputeAlphaScale);
// This function is not a good way to do this
// but we cannot change it without changing output pixels
// A better method would be to histogram the channel and scale the histogram to meet the desired threshold
// even if using this binary search method, you should remember which value gave the closest result
// don't assume that each binary search step is an improvement
//
FVector4f MinAlphaScales (0, 0, 0, 0);
FVector4f MaxAlphaScales (4, 4, 4, 4);
FVector4f AlphaScales (1, 1, 1, 1);
//Binary Search to find Alpha Scale
// limit binary search to 8 steps
for (int32 i = 0; i < 8; ++i)
{
FVector4f ComputedCoverages = ComputeAlphaCoverage(AlphaThresholds, AlphaScales, SourceImageData);
UE_LOG(LogTextureCompressor, VeryVerbose, TEXT("Tried AlphaScale = %f ComputedCoverage = %f Goal = %f"), AlphaScales[3], ComputedCoverages[3], Coverages[3] );
for (int32 j = 0; j < 4; ++j)
{
if (AlphaThresholds[j] == 0 || fabsf(ComputedCoverages[j] - Coverages[j]) < KINDA_SMALL_NUMBER)
{
continue;
}
if (ComputedCoverages[j] < Coverages[j])
{
MinAlphaScales[j] = AlphaScales[j];
}
else if (ComputedCoverages[j] > Coverages[j])
{
MaxAlphaScales[j] = AlphaScales[j];
}
// guess alphascale is best at next midpoint :
// this means we wind up returning an alphascale value we have never tested
AlphaScales[j] = (MinAlphaScales[j] + MaxAlphaScales[j]) * 0.5f;
}
// Equals default tolerance is KINDA_SMALL_NUMBER so it checks the same condition as above
if (ComputedCoverages.Equals(Coverages))
{
break;
}
}
UE_LOG(LogTextureCompressor, VeryVerbose, TEXT("Final AlphaScales = %f %f %f %f"), AlphaScales[0], AlphaScales[1], AlphaScales[2], AlphaScales[3] );
return AlphaScales;
}
static void GenerateMip2x2Simple(
const FImageView2D& SourceImageData,
FImageView2D& DestImageData)
{
int32 NumRowsEachJob;
int32 NumJobs = ImageParallelForComputeNumJobsForRows(NumRowsEachJob,DestImageData.SizeX,DestImageData.SizeY);
ParallelFor( TEXT("Texture.GenerateMip2x2Simple.PF"),NumJobs,1, [&](int32 Index)
{
int32 StartIndex = Index * NumRowsEachJob;
int32 EndIndex = FMath::Min(StartIndex + NumRowsEachJob, DestImageData.SizeY);
for (int32 DestY = StartIndex; DestY < EndIndex; ++DestY)
{
float* DestRow = &DestImageData.Access(0, DestY).Component(0);
const float* SourceRow0 = &SourceImageData.Access(0, 2*DestY).Component(0);
const float* SourceRow1 = &SourceImageData.Access(0, 2*DestY+1).Component(0);
const VectorRegister4Float Mul = VectorSetFloat1(0.25f);
for (int32 DestX = 0; DestX < DestImageData.SizeX; DestX++)
{
VectorRegister4Float A = VectorLoad(&SourceRow0[0]);
VectorRegister4Float B = VectorLoad(&SourceRow0[4]);
VectorRegister4Float C = VectorLoad(&SourceRow1[0]);
VectorRegister4Float D = VectorLoad(&SourceRow1[4]);
VectorRegister4Float Sum = VectorAdd(VectorAdd(VectorAdd(A, B), C), D);
VectorRegister4Float Avg = VectorMultiply(Sum, Mul);
VectorStore(Avg, &DestRow[0]);
SourceRow0 += 8;
SourceRow1 += 8;
DestRow += 4;
}
}
});
}
template <EMipGenAddressMode AddressMode>
static void GenerateMipUnfiltered(const FImageView2D& SourceImageData, FImageView2D& DestImageData, FVector4f AlphaScale, uint32 ScaleFactor)
{
int32 NumRowsEachJob;
int32 NumJobs = ImageParallelForComputeNumJobsForRows(NumRowsEachJob, DestImageData.SizeX, DestImageData.SizeY);
ParallelFor(TEXT("Texture.GenerateMipUnfiltered.PF"), NumJobs, 1, [&](int32 Index)
{
VectorRegister4Float AlphaScaleV = VectorLoad(&AlphaScale[0]);
int32 StartIndex = Index * NumRowsEachJob;
int32 EndIndex = FMath::Min(StartIndex + NumRowsEachJob, DestImageData.SizeY);
for (int32 DestY = StartIndex; DestY < EndIndex; ++DestY)
{
for (int32 DestX = 0; DestX < DestImageData.SizeX; DestX++)
{
const int32 SourceX = DestX * ScaleFactor;
const int32 SourceY = DestY * ScaleFactor;
const FLinearColor& Sample = LookupSourceMip<AddressMode>(SourceImageData, SourceX, SourceY);
VectorRegister4Float FilteredColor = VectorLoad(&Sample.Component(0));
// Apply computed alpha scales to each channel
FilteredColor = VectorMultiply(FilteredColor, AlphaScaleV);
// Set the destination pixel.
VectorStore(FilteredColor, &DestImageData.Access(DestX, DestY).Component(0));
}
}
});
}
template <EMipGenAddressMode AddressMode>
static void GenerateMip2x2(const FImageView2D& SourceImageData, FImageView2D& DestImageData, FVector4f AlphaScale, uint32 ScaleFactor)
{
int32 NumRowsEachJob;
int32 NumJobs = ImageParallelForComputeNumJobsForRows(NumRowsEachJob, DestImageData.SizeX, DestImageData.SizeY);
ParallelFor(TEXT("Texture.GenerateMip2x2.PF"), NumJobs, 1, [&](int32 Index)
{
VectorRegister4Float AlphaScaleV = VectorLoad(&AlphaScale[0]);
int32 StartIndex = Index * NumRowsEachJob;
int32 EndIndex = FMath::Min(StartIndex + NumRowsEachJob, DestImageData.SizeY);
for (int32 DestY = StartIndex; DestY < EndIndex; ++DestY)
{
for (int32 DestX = 0; DestX < DestImageData.SizeX; DestX++)
{
const int32 SourceX = DestX * ScaleFactor;
const int32 SourceY = DestY * ScaleFactor;
VectorRegister4Float A = VectorLoad(&LookupSourceMip<AddressMode>(SourceImageData, SourceX + 0, SourceY + 0).Component(0));
VectorRegister4Float B = VectorLoad(&LookupSourceMip<AddressMode>(SourceImageData, SourceX + 1, SourceY + 0).Component(0));
VectorRegister4Float C = VectorLoad(&LookupSourceMip<AddressMode>(SourceImageData, SourceX + 0, SourceY + 1).Component(0));
VectorRegister4Float D = VectorLoad(&LookupSourceMip<AddressMode>(SourceImageData, SourceX + 1, SourceY + 1).Component(0));
VectorRegister4Float FilteredColor = VectorAdd(VectorAdd(VectorAdd(A, B), C), D);
FilteredColor = VectorMultiply(FilteredColor, VectorSetFloat1(0.25f));
// Apply computed alpha scales to each channel
FilteredColor = VectorMultiply(FilteredColor, AlphaScaleV);
// Set the destination pixel.
VectorStore(FilteredColor, &DestImageData.Access(DestX, DestY).Component(0));
}
}
});
}
static void AllocateTempForMips(
TArray<FLinearColor>& TempData,
int32 SourceSizeX,
int32 SourceSizeY,
int32 DestSizeX,
int32 DestSizeY,
bool bDoScaleMipsForAlphaCoverage,
const FImageKernel2D& Kernel,
uint32 ScaleFactor,
bool bSharpenWithoutColorShift,
bool bUnfiltered,
bool bUseNewMipFilter)
{
if (!bUseNewMipFilter)
{
// No need for extra memory if using old 2D filter
return;
}
int32 KernelFilterTableSize = (int32)Kernel.GetFilterTableSize();
if (KernelFilterTableSize == 2 &&
ScaleFactor == 2 &&
DestSizeX * 2 == SourceSizeX &&
DestSizeY * 2 == SourceSizeY &&
!bDoScaleMipsForAlphaCoverage &&
!bUnfiltered)
{
// Will use GenerateMip2x2Simple
return;
}
if (bUnfiltered)
{
// Will use GenerateMipUnfiltered
return;
}
if (KernelFilterTableSize == 2)
{
// Will use GenerateMip2x2
return;
}
int32 NumRowsEachJob;
int32 NumJobs = ImageParallelForComputeNumJobsForRows(NumRowsEachJob, DestSizeX, DestSizeY);
// Enough bytes to have one row per source width for each job thread
// Make sure the rows do not overlap on same cache line
int64 SizeInBytes = (sizeof(FLinearColor) * SourceSizeX + PLATFORM_CACHE_LINE_SIZE) * NumJobs;
int64 ElementCount = FMath::DivideAndRoundUp<int64>(SizeInBytes, sizeof(FLinearColor));
TempData.AddUninitialized(ElementCount);
}
template <EMipGenAddressMode AddressMode, bool bSharpenWithoutColorShift, int KernelSize = 0>
static void GenerateMipSharpened(
const FImageView2D& SourceImageData,
FImageView2D& DestImageData,
const FImageKernel2D& Kernel,
FVector4f AlphaScale,
uint32 ScaleFactor)
{
int32 NumRowsEachJob;
int32 NumJobs = ImageParallelForComputeNumJobsForRows(NumRowsEachJob, DestImageData.SizeX, DestImageData.SizeY);
ParallelFor(TEXT("Texture.GenerateMipSharpened.PF"), NumJobs, 1, [&](int32 Index)
{
// In case kernel size is passed as template argument use it as constant
// This will allow compiler to unroll inner loops below
const int32 KernelFilterTableSize = KernelSize ? KernelSize : (int32)Kernel.GetFilterTableSize();
// if KernelFilterTableSize is odd, centered in-place filter can be applied
// KernelFilterTableSize should be even for standard down-sampling
const int32 KernelCenter = (KernelFilterTableSize - 1) / 2;
VectorRegister4Float AlphaScaleV = VectorLoad(&AlphaScale[0]);
int32 StartIndex = Index * NumRowsEachJob;
int32 EndIndex = FMath::Min(StartIndex + NumRowsEachJob, DestImageData.SizeY);
for (int32 DestY = StartIndex; DestY < EndIndex; ++DestY)
{
for (int32 DestX = 0; DestX < DestImageData.SizeX; DestX++)
{
const int32 SourceX = DestX * ScaleFactor;
const int32 SourceY = DestY * ScaleFactor;
VectorRegister4Float Color = VectorZeroFloat();
for (int32 KernelY = 0; KernelY < KernelFilterTableSize; ++KernelY)
{
for (int32 KernelX = 0; KernelX < KernelFilterTableSize; ++KernelX)
{
const FLinearColor& Sample = LookupSourceMip<AddressMode>(SourceImageData, SourceX + KernelX - KernelCenter, SourceY + KernelY - KernelCenter);
VectorRegister4Float Weight = VectorSetFloat1(Kernel.GetAt(KernelX, KernelY));
VectorRegister4Float WeightSample = VectorMultiply(Weight, VectorLoad(&Sample.Component(0)));
Color = VectorAdd(Color, WeightSample);
}
}
// This condition will be optimized away because it is constant template argument
if (bSharpenWithoutColorShift)
{
VectorRegister4Float SharpenedColor = Color;
// Luminace weights from FLinearColor::GetLuminance() function
VectorRegister4Float LuminanceWeights = MakeVectorRegisterFloat(0.3f, 0.59f, 0.11f, 0.f);
VectorRegister4Float NewLuminance = VectorDot3(SharpenedColor, LuminanceWeights);
// simple 2x2 kernel to compute the color
VectorRegister4Float A = VectorLoad(&LookupSourceMip<AddressMode>(SourceImageData, SourceX + 0, SourceY + 0).Component(0));
VectorRegister4Float B = VectorLoad(&LookupSourceMip<AddressMode>(SourceImageData, SourceX + 1, SourceY + 0).Component(0));
VectorRegister4Float C = VectorLoad(&LookupSourceMip<AddressMode>(SourceImageData, SourceX + 0, SourceY + 1).Component(0));
VectorRegister4Float D = VectorLoad(&LookupSourceMip<AddressMode>(SourceImageData, SourceX + 1, SourceY + 1).Component(0));
VectorRegister4Float FilteredColor = VectorAdd(VectorAdd(VectorAdd(A, B), C), D);
FilteredColor = VectorMultiply(FilteredColor, VectorSetFloat1(0.25f));
VectorRegister4Float OldLuminance = VectorDot3(FilteredColor, LuminanceWeights);
// if (OldLuminance > 0.001f) FilteredColor.RGB *= NewLuminance / OldLuminance;
VectorRegister4Float CompareMask = VectorCompareGT(OldLuminance, VectorSetFloat1(0.001f));
VectorRegister4Float Temp = VectorMultiply(FilteredColor, VectorDivide(NewLuminance, OldLuminance));
FilteredColor = VectorSelect(CompareMask, Temp, FilteredColor);
// FilteredColor.A = SharpenedColor.A
VectorRegister4Float AlphaMask = MakeVectorRegisterFloatMask(0, 0, 0, 0xffffffff);
FilteredColor = VectorSelect(AlphaMask, SharpenedColor, FilteredColor);
// Apply computed alpha scales to each channel
FilteredColor = VectorMultiply(FilteredColor, AlphaScaleV);
// Set the destination pixel.
VectorStore(FilteredColor, &DestImageData.Access(DestX, DestY).Component(0));
}
else
{
// Apply computed alpha scales to each channel
Color = VectorMultiply(Color, AlphaScaleV);
// Set the destination pixel.
VectorStore(Color, &DestImageData.Access(DestX, DestY).Component(0));
}
}
}
});
}
template <EMipGenAddressMode AddressMode, int KernelSize = 0>
static void GenerateMipSharpenedSeparable(
const FImageView2D& SourceImageData,
TArray<FLinearColor>& TempData,
FImageView2D& DestImageData,
const FImageKernel2D& Kernel,
FVector4f AlphaScale,
uint32 ScaleFactor)
{
int32 NumRowsEachJob;
int32 NumJobs = ImageParallelForComputeNumJobsForRows(NumRowsEachJob, DestImageData.SizeX, DestImageData.SizeY);
// Verify that caller has allocated proper amount of bytes for temporary storage
// This is allocated in AllocateTempForMips function above
check(TempData.Num() >= SourceImageData.SizeX * NumJobs);
ParallelFor(TEXT("Texture.GenerateMipSharpenedSeparable.PF"), NumJobs, 1, [&](int32 Index)
{
// In case kernel size is passed as template argument use it as constant
// This will allow compiler to unroll inner loops below
const int32 KernelFilterTableSize = KernelSize ? KernelSize : (int32)Kernel.GetFilterTableSize();
// if KernelFilterTableSize is odd, centered in-place filter can be applied
// KernelFilterTableSize should be even for standard down-sampling
const int32 KernelCenter = (KernelFilterTableSize - 1) / 2;
VectorRegister4Float AlphaScaleV = VectorLoad(&AlphaScale[0]);
int32 StartIndex = Index * NumRowsEachJob;
int32 EndIndex = FMath::Min(StartIndex + NumRowsEachJob, DestImageData.SizeY);
FLinearColor* Temp = &TempData[Index * (TempData.Num() / NumJobs)];
for (int32 DestY = StartIndex; DestY < EndIndex; ++DestY)
{
const int32 SourceY = DestY * ScaleFactor;
for (int32 SourceX = 0; SourceX < SourceImageData.SizeX; SourceX++)
{
VectorRegister4Float Color = VectorZeroFloat();
for (int32 KernelY = 0; KernelY < KernelFilterTableSize; ++KernelY)
{
const FLinearColor& Sample = LookupSourceMip<AddressMode>(SourceImageData, SourceX, SourceY + KernelY - KernelCenter);
VectorRegister4Float Weight = VectorSetFloat1(Kernel.Get1D(KernelY));
VectorRegister4Float WeightSample = VectorMultiply(Weight, VectorLoad(&Sample.Component(0)));
Color = VectorAdd(Color, WeightSample);
}
VectorStore(Color, &Temp[SourceX].Component(0));
}
for (int32 DestX = 0; DestX < DestImageData.SizeX; DestX++)
{
const int32 SourceX = DestX * ScaleFactor;
VectorRegister4Float Color = VectorZeroFloat();
for (int32 KernelX = 0; KernelX < KernelFilterTableSize; ++KernelX)
{
const FLinearColor& Sample = LookupSourceMip<AddressMode>(Temp, SourceImageData.SizeX, SourceX + KernelX - KernelCenter);
VectorRegister4Float Weight = VectorSetFloat1(Kernel.Get1D(KernelX));
VectorRegister4Float WeightSample = VectorMultiply(Weight, VectorLoad(&Sample.Component(0)));
Color = VectorAdd(Color, WeightSample);
}
// Apply computed alpha scales to each channel
Color = VectorMultiply(Color, AlphaScaleV);
// Set the destination pixel.
VectorStore(Color, &DestImageData.Access(DestX, DestY).Component(0));
}
}
});
}
/**
* Generates a mip-map for an 2D B8G8R8A8 image using a filter with possible sharpening
* @param SourceImageData - The source image's data.
* @param TempData - Temporary storage required by separable mip filter, call AllocateTempForMips function to allocate it
* @param DestImageData - The destination image's data.
* @param ImageFormat - The format of both the source and destination images.
* @param FilterTable2D - [FilterTableSize * FilterTableSize]
* @param FilterTableSize - >= 2
* @param ScaleFactor 1 / 2:for downsampling
* @param bUseNewMipFilter - pass true to use new separatble mip filter
*/
template <EMipGenAddressMode AddressMode>
static void GenerateSharpenedMipB8G8R8A8Templ(
const FImageView2D& SourceImageData,
TArray<FLinearColor>& TempData,
FImageView2D& DestImageData,
bool bDoScaleMipsForAlphaCoverage,
const FVector4f AlphaCoverages,
const FVector4f AlphaThresholds,
const FImageKernel2D& Kernel,
uint32 ScaleFactor,
bool bSharpenWithoutColorShift,
bool bUnfiltered,
bool bUseNewMipFilter)
{
check( ScaleFactor == 1 || ScaleFactor == 2 );
check( (SourceImageData.SizeX/ScaleFactor) == DestImageData.SizeX || DestImageData.SizeX == 1 );
check( (SourceImageData.SizeY/ScaleFactor) == DestImageData.SizeY || DestImageData.SizeY == 1 );
int32 KernelFilterTableSize = (int32) Kernel.GetFilterTableSize();
checkf( KernelFilterTableSize >= 2, TEXT("Kernel table size %d, expected at least 2!"), KernelFilterTableSize);
if ( KernelFilterTableSize == 2 )
{
// 2x2 is always box filter
check( Kernel.GetAt(0,0) == 0.25f );
}
// Keep conditions here in sync with same conditions inside AllocateTempForMips function
if ( KernelFilterTableSize == 2 &&
ScaleFactor == 2 &&
DestImageData.SizeX*2 == SourceImageData.SizeX &&
DestImageData.SizeY*2 == SourceImageData.SizeY &&
! bDoScaleMipsForAlphaCoverage &&
! bUnfiltered )
{
// bSharpenWithoutColorShift is ignored for 2x2 filter
GenerateMip2x2Simple(SourceImageData,DestImageData);
return;
}
FVector4f AlphaScale(1, 1, 1, 1);
if (bDoScaleMipsForAlphaCoverage)
{
AlphaScale = ComputeAlphaScale(AlphaCoverages, AlphaThresholds, SourceImageData);
}
if (bUnfiltered)
{
GenerateMipUnfiltered<AddressMode>(SourceImageData, DestImageData, AlphaScale, ScaleFactor);
return;
}
if (KernelFilterTableSize == 2)
{
GenerateMip2x2<AddressMode>(SourceImageData, DestImageData, AlphaScale, ScaleFactor);
return;
}
if (bUseNewMipFilter)
{
if (KernelFilterTableSize == 8)
{
GenerateMipSharpenedSeparable<AddressMode, 8>(SourceImageData, TempData, DestImageData, Kernel, AlphaScale, ScaleFactor);
}
else
{
GenerateMipSharpenedSeparable<AddressMode>(SourceImageData, TempData, DestImageData, Kernel, AlphaScale, ScaleFactor);
}
}
else
{
if (bSharpenWithoutColorShift)
{
if (KernelFilterTableSize == 8)
{
GenerateMipSharpened<AddressMode, true, 8>(SourceImageData, DestImageData, Kernel, AlphaScale, ScaleFactor);
}
else
{
GenerateMipSharpened<AddressMode, true>(SourceImageData, DestImageData, Kernel, AlphaScale, ScaleFactor);
}
}
else
{
if (KernelFilterTableSize == 8)
{
GenerateMipSharpened<AddressMode, false, 8>(SourceImageData, DestImageData, Kernel, AlphaScale, ScaleFactor);
}
else
{
GenerateMipSharpened<AddressMode, false>(SourceImageData, DestImageData, Kernel, AlphaScale, ScaleFactor);
}
}
}
}
// to switch conveniently between different texture wrapping modes for the mip map generation
// the template can optimize the inner loop using a constant AddressMode
static void GenerateSharpenedMipB8G8R8A8(
const FImageView2D& SourceImageData,
const FImageView2D& SourceImageData2, // Only used with volume texture.
TArray<FLinearColor>& TempData,
FImageView2D& DestImageData,
EMipGenAddressMode AddressMode,
bool bDoScaleMipsForAlphaCoverage,
FVector4f AlphaCoverages,
FVector4f AlphaThresholds,
const FImageKernel2D &Kernel,
uint32 ScaleFactor,
bool bSharpenWithoutColorShift,
bool bUnfiltered,
bool bUseNewMipFilter
)
{
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.GenerateSharpenedMip);
switch(AddressMode)
{
case MGTAM_Wrap:
GenerateSharpenedMipB8G8R8A8Templ<MGTAM_Wrap>(SourceImageData, TempData, DestImageData, bDoScaleMipsForAlphaCoverage, AlphaCoverages, AlphaThresholds, Kernel, ScaleFactor, bSharpenWithoutColorShift, bUnfiltered, bUseNewMipFilter);
break;
case MGTAM_Clamp:
GenerateSharpenedMipB8G8R8A8Templ<MGTAM_Clamp>(SourceImageData, TempData, DestImageData, bDoScaleMipsForAlphaCoverage, AlphaCoverages, AlphaThresholds, Kernel, ScaleFactor, bSharpenWithoutColorShift, bUnfiltered, bUseNewMipFilter);
break;
case MGTAM_BorderBlack:
GenerateSharpenedMipB8G8R8A8Templ<MGTAM_BorderBlack>(SourceImageData, TempData, DestImageData, bDoScaleMipsForAlphaCoverage, AlphaCoverages, AlphaThresholds, Kernel, ScaleFactor, bSharpenWithoutColorShift, bUnfiltered, bUseNewMipFilter);
break;
default:
check(0);
}
// For volume texture, do the average between the 2.
if (SourceImageData2.IsValid() && !bUnfiltered)
{
FImage Temp(DestImageData.SizeX, DestImageData.SizeY, 1, ERawImageFormat::RGBA32F);
FImageView2D TempImageData (Temp, 0);
switch(AddressMode)
{
case MGTAM_Wrap:
GenerateSharpenedMipB8G8R8A8Templ<MGTAM_Wrap>(SourceImageData2, TempData, TempImageData, bDoScaleMipsForAlphaCoverage, AlphaCoverages, AlphaThresholds, Kernel, ScaleFactor, bSharpenWithoutColorShift, bUnfiltered, bUseNewMipFilter);
break;
case MGTAM_Clamp:
GenerateSharpenedMipB8G8R8A8Templ<MGTAM_Clamp>(SourceImageData2, TempData, TempImageData, bDoScaleMipsForAlphaCoverage, AlphaCoverages, AlphaThresholds, Kernel, ScaleFactor, bSharpenWithoutColorShift, bUnfiltered, bUseNewMipFilter);
break;
case MGTAM_BorderBlack:
GenerateSharpenedMipB8G8R8A8Templ<MGTAM_BorderBlack>(SourceImageData2, TempData, TempImageData, bDoScaleMipsForAlphaCoverage, AlphaCoverages, AlphaThresholds, Kernel, ScaleFactor, bSharpenWithoutColorShift, bUnfiltered, bUseNewMipFilter);
break;
default:
check(0);
}
const int32 NumColors = DestImageData.SizeX * DestImageData.SizeY;
for (int32 ColorIndex = 0; ColorIndex < NumColors; ++ColorIndex)
{
DestImageData.SliceColors[ColorIndex] =
(DestImageData.SliceColors[ColorIndex] + TempImageData.SliceColors[ColorIndex]) * 0.5f;
}
}
}
// Update border texels after normal mip map generation to preserve the colors there (useful for particles and decals).
static void GenerateMipBorder(
const FImageView2D& SrcImageData,
FImageView2D& DestImageData
)
{
check( (SrcImageData.SizeX/2) == DestImageData.SizeX || DestImageData.SizeX == 1 );
check( (SrcImageData.SizeY/2) == DestImageData.SizeY || DestImageData.SizeY == 1 );
// this check is unnecessary if we always used MGTAM_Clamp here;
bool bIsPow2 = FMath::IsPowerOfTwo(SrcImageData.SizeX) && FMath::IsPowerOfTwo(SrcImageData.SizeY);
for ( int32 DestY = 0; DestY < DestImageData.SizeY; DestY++ )
{
for ( int32 DestX = 0; DestX < DestImageData.SizeX; )
{
FLinearColor FilteredColor(0, 0, 0, 0);
{
float WeightSum = 0.0f;
for ( int32 KernelY = 0; KernelY < 2; ++KernelY )
{
for ( int32 KernelX = 0; KernelX < 2; ++KernelX )
{
const int32 SourceX = DestX * 2 + KernelX;
const int32 SourceY = DestY * 2 + KernelY;
// only average the source border
if ( SourceX == 0 ||
SourceX == SrcImageData.SizeX - 1 ||
SourceY == 0 ||
SourceY == SrcImageData.SizeY - 1 )
{
// I think this should have just always been MGTAM_Clamp
// but that changes existing content, so preserve old behavior of using _Wrap :(
FLinearColor Sample;
if ( bIsPow2 )
{
Sample = LookupSourceMip<MGTAM_Wrap>( SrcImageData, SourceX, SourceY );
}
else
{
Sample = LookupSourceMip<MGTAM_Clamp>( SrcImageData, SourceX, SourceY );
}
FilteredColor += Sample;
WeightSum += 1.0f;
}
}
}
FilteredColor /= WeightSum;
}
// Set the destination pixel.
//FLinearColor& DestColor = *(DestImageData.AsRGBA32F() + DestX + DestY * DestImageData.SizeX);
FLinearColor& DestColor = DestImageData.Access(DestX, DestY);
DestColor = FilteredColor;
++DestX;
if ( DestY > 0 &&
DestY < DestImageData.SizeY - 1 &&
DestX > 0 &&
DestX < DestImageData.SizeX - 1 )
{
// jump over the non border area
DestX += FMath::Max( 1, DestImageData.SizeX - 2 );
}
}
}
}
// how should be treat lookups outside of the image
static EMipGenAddressMode ComputeAddressMode(const FImage & Image,const FTextureBuildSettings& Settings)
{
// note: all textures Wrap by default even if their address mode is set to Clamp !?
EMipGenAddressMode AddressMode = MGTAM_Wrap;
// Wrap uses AND so requires pow2 sizes ; change to Clamp if nonpow2
bool bIsPow2 = FMath::IsPowerOfTwo(Image.SizeX) && FMath::IsPowerOfTwo(Image.SizeY);
// 2d address mode, no need to look at volume z :
/*
if ( Settings.bVolume && ! FMath::IsPowerOfTwo(Image.NumSlices) )
{
bIsPow2 = false;
}
*/
if ( ! bIsPow2 )
{
AddressMode = MGTAM_Clamp;
}
if(Settings.bPreserveBorder)
{
AddressMode = Settings.bBorderColorBlack ? MGTAM_BorderBlack : MGTAM_Clamp;
}
return AddressMode;
}
static void GenerateTopMip(const FImage& SrcImage, FImage& DestImage, const FTextureBuildSettings& Settings)
{
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.GenerateTopMip);
// GenerateTopMip is only used for ApplyCompositeTexture
// bApplyKernelToTopMip is not exposed to Texture GUI
EMipGenAddressMode AddressMode = ComputeAddressMode(SrcImage,Settings);
FImageKernel2D KernelDownsample;
if ( Settings.MipSharpening < 0.f )
{
// negative Sharpening is a Gaussian
// this can make centered ("odd") filters, so the image doesn't shift
int32 OddMipKernelSize = Settings.SharpenMipKernelSize | 1;
KernelDownsample.BuildSeparatableGaussWithSharpen( OddMipKernelSize, Settings.MipSharpening );
}
else
{
// non-Gaussians only support "even" filters
// this causes a half-pixel shift of the top mip
// warn but then go ahead and do as requested
UE_LOG(LogTextureCompressor, Warning, TEXT("GenerateTopMip used with non-Gaussian blur filter will cause half pixel shift"));
KernelDownsample.BuildSeparatableGaussWithSharpen( Settings.SharpenMipKernelSize, Settings.MipSharpening );
}
DestImage.Init(SrcImage.SizeX, SrcImage.SizeY, SrcImage.NumSlices, SrcImage.Format, SrcImage.GammaSpace);
const bool bSharpenWithoutColorShift = Settings.bSharpenWithoutColorShift;
const bool bUnfiltered = Settings.MipGenSettings == TMGS_Unfiltered;
const bool bUseNewMipFilter = Settings.bUseNewMipFilter;
TArray<FLinearColor> TempData;
AllocateTempForMips(TempData, SrcImage.SizeX, SrcImage.SizeY, DestImage.SizeX, DestImage.SizeY, false, KernelDownsample, 1, bSharpenWithoutColorShift, bUnfiltered, bUseNewMipFilter);
for (int32 SliceIndex = 0; SliceIndex < SrcImage.NumSlices; ++SliceIndex)
{
FImageView2D SrcView((FImage&)SrcImage, SliceIndex);
FImageView2D DestView(DestImage, SliceIndex);
// generate DestImage: down sample with sharpening
GenerateSharpenedMipB8G8R8A8(
SrcView,
FImageView2D(),
TempData,
DestView,
AddressMode,
false,
FVector4f(0, 0, 0, 0),
FVector4f(0, 0, 0, 0),
KernelDownsample,
1,
Settings.bSharpenWithoutColorShift,
bUnfiltered,
bUseNewMipFilter);
}
}
static FLinearColor LookupSourceMipBilinear(const FImageView2D& SourceImageData, float X, float Y)
{
X = FMath::Clamp(X, 0.f, SourceImageData.SizeX - 1.f);
Y = FMath::Clamp(Y, 0.f, SourceImageData.SizeY - 1.f);
int32 IntX0 = FMath::FloorToInt(X);
int32 IntY0 = FMath::FloorToInt(Y);
float FractX = X - IntX0;
float FractY = Y - IntY0;
int32 IntX1 = FMath::Min(IntX0+1, SourceImageData.SizeX-1);
int32 IntY1 = FMath::Min(IntY0+1, SourceImageData.SizeY-1);
FLinearColor Sample00 = SourceImageData.Access(IntX0,IntY0);
FLinearColor Sample10 = SourceImageData.Access(IntX1,IntY0);
FLinearColor Sample01 = SourceImageData.Access(IntX0,IntY1);
FLinearColor Sample11 = SourceImageData.Access(IntX1,IntY1);
FLinearColor Sample0 = FMath::Lerp(Sample00, Sample10, FractX);
FLinearColor Sample1 = FMath::Lerp(Sample01, Sample11, FractX);
return FMath::Lerp(Sample0, Sample1, FractY);
}
struct FTextureDownscaleSettings
{
int32 BlockSize;
float Downscale;
uint8 DownscaleOptions;
bool UseNewMipFilter;
};
static void DownscaleImage(const FImage& SrcImage, FImage& DstImage, const FTextureDownscaleSettings& Settings)
{
if (Settings.Downscale <= 1.f)
{
return;
}
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.DownscaleImage);
float Downscale = FMath::Clamp(Settings.Downscale, 1.f, 8.f);
int32 FinalSizeX = FMath::CeilToInt(SrcImage.SizeX / Downscale);
int32 FinalSizeY = FMath::CeilToInt(SrcImage.SizeY / Downscale);
// compute final size respecting image block size
if (Settings.BlockSize > 1
&& SrcImage.SizeX % Settings.BlockSize == 0
&& SrcImage.SizeY % Settings.BlockSize == 0)
{
int32 NumBlocksX = SrcImage.SizeX / Settings.BlockSize;
int32 NumBlocksY = SrcImage.SizeY / Settings.BlockSize;
int32 GCD = FMath::GreatestCommonDivisor(NumBlocksX, NumBlocksY);
int32 RatioX = NumBlocksX/GCD;
int32 RatioY = NumBlocksY/GCD;
int32 FinalNumBlocksX = (int32)FMath::GridSnap((float)FinalSizeX/Settings.BlockSize, (float)RatioX);
int32 FinalNumBlocksY = FinalNumBlocksX/RatioX*RatioY;
FinalSizeX = FinalNumBlocksX*Settings.BlockSize;
FinalSizeY = FinalNumBlocksY*Settings.BlockSize;
}
Downscale = (float)SrcImage.SizeX / FinalSizeX;
FImage Image0;
FImage Image1;
FImage* ImageChain[2] = {&const_cast<FImage&>(SrcImage), &Image1};
const bool bUnfiltered = Settings.DownscaleOptions == (uint8)ETextureDownscaleOptions::Unfiltered;
const bool bUseNewMipFilter = Settings.UseNewMipFilter;
// Scaledown using 2x2 average, use user specified filtering only for last iteration
FImageKernel2D AvgKernel;
AvgKernel.BuildSeparatableGaussWithSharpen(2);
TArray<FLinearColor> TempData;
AllocateTempForMips(TempData, SrcImage.SizeX, SrcImage.SizeY, SrcImage.SizeX / 2, SrcImage.SizeY / 2, false, AvgKernel, 2, false, bUnfiltered, bUseNewMipFilter);
int32 NumIterations = 0;
while(Downscale > 2.0f)
{
int32 DstSizeX = ImageChain[0]->SizeX / 2;
int32 DstSizeY = ImageChain[0]->SizeY / 2;
ImageChain[1]->Init(DstSizeX, DstSizeY, ImageChain[0]->NumSlices, ImageChain[0]->Format, ImageChain[0]->GammaSpace);
FImageView2D SrcImageData(*ImageChain[0], 0);
FImageView2D DstImageData(*ImageChain[1], 0);
GenerateSharpenedMipB8G8R8A8Templ<MGTAM_Clamp>(
SrcImageData,
TempData,
DstImageData,
false,
FVector4f(0, 0, 0, 0),
FVector4f(0, 0, 0, 0),
AvgKernel,
2,
false,
bUnfiltered,
bUseNewMipFilter);
if (NumIterations == 0)
{
ImageChain[0] = &Image0;
}
Swap(ImageChain[0], ImageChain[1]);
NumIterations++;
Downscale/= 2.f;
}
if (ImageChain[0]->SizeX == FinalSizeX &&
ImageChain[0]->SizeY == FinalSizeY)
{
ImageChain[0]->CopyTo(DstImage, ImageChain[0]->Format, ImageChain[0]->GammaSpace);
return;
}
int32 KernelSize = 2;
float Sharpening = 0.0f;
if (Settings.DownscaleOptions >= (uint8)ETextureDownscaleOptions::Sharpen0 && Settings.DownscaleOptions <= (uint8)ETextureDownscaleOptions::Sharpen10)
{
// 0 .. 2.0f
Sharpening = ((int32)Settings.DownscaleOptions - (int32)ETextureDownscaleOptions::Sharpen0) * 0.2f;
KernelSize = 8;
}
bool bBilinear = Settings.DownscaleOptions == (uint8)ETextureDownscaleOptions::SimpleAverage;
FImageKernel2D KernelSharpen;
KernelSharpen.BuildSeparatableGaussWithSharpen(KernelSize, Sharpening);
const int32 KernelCenter = (int32)KernelSharpen.GetFilterTableSize() / 2 - 1;
ImageChain[1] = &DstImage;
if (ImageChain[0] == ImageChain[1])
{
ImageChain[0]->CopyTo(Image0, ImageChain[0]->Format, ImageChain[0]->GammaSpace);
ImageChain[0] = &Image0;
}
ImageChain[1]->Init(FinalSizeX, FinalSizeY, ImageChain[0]->NumSlices, ImageChain[0]->Format, ImageChain[0]->GammaSpace);
Downscale = (float)ImageChain[0]->SizeX / FinalSizeX;
FImageView2D SrcImageData(*ImageChain[0], 0);
FImageView2D DstImageData(*ImageChain[1], 0);
for (int32 Y = 0; Y < FinalSizeY; ++Y)
{
float SourceY = Y * Downscale;
int32 IntSourceY = FMath::RoundToInt(SourceY);
for (int32 X = 0; X < FinalSizeX; ++X)
{
float SourceX = X * Downscale;
int32 IntSourceX = FMath::RoundToInt(SourceX);
FLinearColor FilteredColor(0,0,0,0);
if (bUnfiltered)
{
FilteredColor = LookupSourceMip<MGTAM_Clamp>(SrcImageData, IntSourceX, IntSourceY);
}
else if(bBilinear)
{
FilteredColor = LookupSourceMipBilinear(SrcImageData, SourceX, SourceY);
}
else
{
for (uint32 KernelY = 0; KernelY < KernelSharpen.GetFilterTableSize(); ++KernelY)
{
for (uint32 KernelX = 0; KernelX < KernelSharpen.GetFilterTableSize(); ++KernelX)
{
float Weight = KernelSharpen.GetAt(KernelX, KernelY);
FLinearColor Sample = LookupSourceMipBilinear(SrcImageData, SourceX + KernelX - KernelCenter, SourceY + KernelY - KernelCenter);
FilteredColor += Weight * Sample;
}
}
}
// Set the destination pixel.
FLinearColor& DestColor = DstImageData.Access(X, Y);
DestColor = FilteredColor;
}
}
}
void ITextureCompressorModule::GenerateMipChain(
const FTextureBuildSettings& Settings,
const FImage& BaseImage,
TArray<FImage> &OutMipChain,
uint32 MipChainDepth
)
{
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.GenerateMipChain);
// MipChainDepth is the number more to make, OutMipChain has some already
// typically BaseImage == OutMipChain.Last()
if ( MipChainDepth == 0 )
{
return;
}
check(BaseImage.Format == ERawImageFormat::RGBA32F);
const FImage& BaseMip = BaseImage;
const int32 SrcWidth = BaseMip.SizeX;
const int32 SrcHeight= BaseMip.SizeY;
const int32 SrcNumSlices = BaseMip.NumSlices;
const ERawImageFormat::Type ImageFormat = ERawImageFormat::RGBA32F;
const FImage* IntermediateSrcPtr;
FImage* IntermediateDstPtr;
// This will be used as a buffer for the mip processing
FImage FirstTempImage;
if (BaseMip.GammaSpace != EGammaSpace::Linear)
{
// copy base mip
BaseMip.CopyTo(FirstTempImage, ERawImageFormat::RGBA32F, EGammaSpace::Linear);
IntermediateSrcPtr = &FirstTempImage;
}
else
{
// It looks like the BaseMip can be reused for the intermediate source of the second Mip (assuming that the format was check earlier to be RGBA32F)
IntermediateSrcPtr = &BaseMip;
// This temp image will be first used as an intermediate destination for the third mip in the chain
FirstTempImage.Init( FMath::Max<uint32>( 1, SrcWidth >> 2 ), FMath::Max<uint32>( 1, SrcHeight >> 2 ), Settings.bVolume ? FMath::Max<uint32>( 1, SrcNumSlices >> 2 ) : SrcNumSlices, ImageFormat );
}
// The image for the first destination
FImage SecondTempImage(FMath::Max<uint32>( 1, SrcWidth >> 1 ), FMath::Max<uint32>( 1, SrcHeight >> 1 ), Settings.bVolume ? FMath::Max<uint32>( 1, SrcNumSlices >> 1 ) : SrcNumSlices, ImageFormat);
IntermediateDstPtr = &SecondTempImage;
// Filtering kernels.
FImageKernel2D KernelSimpleAverage;
FImageKernel2D KernelDownsample;
KernelSimpleAverage.BuildSeparatableGaussWithSharpen( 2 );
KernelDownsample.BuildSeparatableGaussWithSharpen( Settings.SharpenMipKernelSize, Settings.MipSharpening );
//@TODO : add a true 3D kernel.
EMipGenAddressMode AddressMode = ComputeAddressMode(*IntermediateSrcPtr,Settings);
bool bReDrawBorder = false;
if( Settings.bPreserveBorder )
{
bReDrawBorder = !Settings.bBorderColorBlack;
}
// Calculate alpha coverage value to preserve along mip chain
FVector4f AlphaCoverages(0, 0, 0, 0);
if ( Settings.bDoScaleMipsForAlphaCoverage )
{
check(Settings.AlphaCoverageThresholds != FVector4f(0,0,0,0));
check(IntermediateSrcPtr);
const FImageView2D IntermediateSrcView = FImageView2D::ConstructConst(*IntermediateSrcPtr, 0);
const FVector4f AlphaScales(1, 1, 1, 1);
AlphaCoverages = ComputeAlphaCoverage(Settings.AlphaCoverageThresholds, AlphaScales, IntermediateSrcView);
}
TArray<FLinearColor> DownsampleTempData;
TArray<FLinearColor> AverageTempData;
const bool bDoScaleMipsForAlphaCoverage = Settings.bDoScaleMipsForAlphaCoverage;
const bool bSharpenWithoutColorShift = Settings.bSharpenWithoutColorShift;
const bool bUnfiltered = Settings.MipGenSettings == TMGS_Unfiltered;
const bool bUseNewMipFilter = Settings.bUseNewMipFilter;
AllocateTempForMips(DownsampleTempData, BaseMip.SizeX, BaseMip.SizeY, SecondTempImage.SizeX, SecondTempImage.SizeY, bDoScaleMipsForAlphaCoverage, KernelDownsample, 2, bSharpenWithoutColorShift, bUnfiltered, bUseNewMipFilter);
AllocateTempForMips(AverageTempData, BaseMip.SizeX, BaseMip.SizeY, SecondTempImage.SizeX, SecondTempImage.SizeY, bDoScaleMipsForAlphaCoverage, KernelSimpleAverage, 2, bSharpenWithoutColorShift, bUnfiltered, bUseNewMipFilter);
// Generate mips
// default value of MipChainDepth is MAX_uint32, means generate all mips down to 1x1
// (break inside the loop)
for (; MipChainDepth != 0 ; --MipChainDepth)
{
check(IntermediateSrcPtr && IntermediateDstPtr);
const FImage& IntermediateSrc = *IntermediateSrcPtr;
FImage& IntermediateDst = *IntermediateDstPtr;
if ( IntermediateSrc.SizeX == 1 && IntermediateSrc.SizeY == 1 && (!Settings.bVolume || IntermediateSrc.NumSlices == 1))
{
// should not have been called, starting mip is already small enough
check(0);
break;
}
// add new mip to TArray<FImage> &OutMipChain :
// placement new on TArray does AddUninitialized then constructs in the last element
FImage& DestImage = *new(OutMipChain) FImage(IntermediateDst.SizeX, IntermediateDst.SizeY, IntermediateDst.NumSlices, ImageFormat);
for (int32 SliceIndex = 0; SliceIndex < IntermediateDst.NumSlices; ++SliceIndex)
{
const int32 SrcSliceIndex = Settings.bVolume ? (SliceIndex * 2) : SliceIndex;
const FImageView2D IntermediateSrcView = FImageView2D::ConstructConst(IntermediateSrc, SrcSliceIndex);
FImageView2D IntermediateSrcView2;
if ( Settings.bVolume )
{
if ( SrcSliceIndex + 1 < IntermediateSrc.NumSlices )
{
IntermediateSrcView2 = FImageView2D::ConstructConst(IntermediateSrc, SrcSliceIndex + 1);
}
else
{
// nonpow2 volume sizeZ , clamp slice index
IntermediateSrcView2 = FImageView2D::ConstructConst(IntermediateSrc, SrcSliceIndex);
}
}
FImageView2D DestView(DestImage, SliceIndex);
FImageView2D IntermediateDstView(IntermediateDst, SliceIndex);
// DestView is the output mip
GenerateSharpenedMipB8G8R8A8(
IntermediateSrcView,
IntermediateSrcView2,
DownsampleTempData,
DestView,
AddressMode,
bDoScaleMipsForAlphaCoverage,
AlphaCoverages,
Settings.AlphaCoverageThresholds,
KernelDownsample,
2,
bSharpenWithoutColorShift,
bUnfiltered,
bUseNewMipFilter);
// generate IntermediateDstImage:
// IntermediateDstImage will be the source for the next mip
if ( Settings.bDownsampleWithAverage )
{
// down sample without sharpening for the next iteration
// bDownsampleWithAverage comes from GetMipGenSettings
// it is on by default for all cases except Blur
// it means every mip is generated *twice*
// the output mip is made above using Sharpen from the IntermediateSrc
// then the next source is made here using 2x2 ("SimpleAverage")
// the next IntermediateSrc is not my outputmip, it's what is made here
GenerateSharpenedMipB8G8R8A8(
IntermediateSrcView,
IntermediateSrcView2,
AverageTempData,
IntermediateDstView,
AddressMode,
bDoScaleMipsForAlphaCoverage,
AlphaCoverages,
Settings.AlphaCoverageThresholds,
KernelSimpleAverage,
2,
bSharpenWithoutColorShift,
bUnfiltered,
bUseNewMipFilter);
}
}
if ( Settings.bDownsampleWithAverage == false )
{
FMemory::Memcpy( (&IntermediateDst.AsRGBA32F()[0]), (&DestImage.AsRGBA32F()[0]),
IntermediateDst.SizeX * IntermediateDst.SizeY * IntermediateDst.NumSlices * sizeof(FLinearColor) );
}
if ( bReDrawBorder )
{
for (int32 SliceIndex = 0; SliceIndex < IntermediateDst.NumSlices; ++SliceIndex)
{
const FImageView2D IntermediateSrcView = FImageView2D::ConstructConst(IntermediateSrc, SliceIndex);
FImageView2D DestView(DestImage, SliceIndex);
FImageView2D IntermediateDstView(IntermediateDst, SliceIndex);
GenerateMipBorder( IntermediateSrcView, DestView );
GenerateMipBorder( IntermediateSrcView, IntermediateDstView );
}
}
// Once we've created mip-maps down to 1x1, we're done.
if ( IntermediateDst.SizeX == 1 && IntermediateDst.SizeY == 1 && (!Settings.bVolume || IntermediateDst.NumSlices == 1))
{
break;
}
// last destination becomes next source
if (IntermediateDstPtr == &SecondTempImage)
{
IntermediateDstPtr = &FirstTempImage;
IntermediateSrcPtr = &SecondTempImage;
}
else
{
IntermediateDstPtr = &SecondTempImage;
IntermediateSrcPtr = &FirstTempImage;
}
// Update the destination size for the next iteration.
IntermediateDstPtr->SizeX = FMath::Max<uint32>( 1, IntermediateSrcPtr->SizeX >> 1 );
IntermediateDstPtr->SizeY = FMath::Max<uint32>( 1, IntermediateSrcPtr->SizeY >> 1 );
IntermediateDstPtr->NumSlices = Settings.bVolume ? FMath::Max<uint32>( 1, IntermediateSrcPtr->NumSlices >> 1 ) : SrcNumSlices;
}
}
/*------------------------------------------------------------------------------
Angular Filtering for HDR Cubemaps.
------------------------------------------------------------------------------*/
/**
* View in to an image that allows access by converting a direction to longitude and latitude.
*/
struct FImageViewLongLat
{
/** Image colors. */
FLinearColor* ImageColors;
/** Width of the image. */
int32 SizeX;
/** Height of the image. */
int32 SizeY;
/** Initialization constructor. */
explicit FImageViewLongLat(FImage& Image, int32 SliceIndex)
{
SizeX = Image.SizeX;
SizeY = Image.SizeY;
ImageColors = (&Image.AsRGBA32F()[0]) + SliceIndex * SizeY * SizeX;
}
/** Wraps X around W. */
static void WrapTo(int32& X, int32 W)
{
X = X % W;
if(X < 0)
{
X += W;
}
}
/** Const access to a texel. */
FLinearColor Access(int32 X, int32 Y) const
{
return ImageColors[X + Y * SizeX];
}
/** Makes a filtered lookup. */
FLinearColor LookupFiltered(float X, float Y) const
{
int32 X0 = (int32)floorf(X);
int32 Y0 = (int32)floorf(Y);
float FracX = X - X0;
float FracY = Y - Y0;
int32 X1 = X0 + 1;
int32 Y1 = Y0 + 1;
WrapTo(X0, SizeX);
WrapTo(X1, SizeX);
Y0 = FMath::Clamp(Y0, 0, (int32)(SizeY - 1));
Y1 = FMath::Clamp(Y1, 0, (int32)(SizeY - 1));
FLinearColor CornerRGB00 = Access(X0, Y0);
FLinearColor CornerRGB10 = Access(X1, Y0);
FLinearColor CornerRGB01 = Access(X0, Y1);
FLinearColor CornerRGB11 = Access(X1, Y1);
FLinearColor CornerRGB0 = FMath::Lerp(CornerRGB00, CornerRGB10, FracX);
FLinearColor CornerRGB1 = FMath::Lerp(CornerRGB01, CornerRGB11, FracX);
return FMath::Lerp(CornerRGB0, CornerRGB1, FracY);
}
/** Makes a filtered lookup using a direction. */
FLinearColor LookupLongLat(FVector NormalizedDirection) const
{
// see http://gl.ict.usc.edu/Data/HighResProbes
// latitude-longitude panoramic format = equirectangular mapping
float X = (1 + atan2(NormalizedDirection.X, - NormalizedDirection.Z) / PI) / 2 * SizeX;
float Y = acos(NormalizedDirection.Y) / PI * SizeY;
return LookupFiltered(X, Y);
}
};
// transform world space vector to a space relative to the face
static FVector TransformSideToWorldSpace(uint32 CubemapFace, FVector InDirection)
{
float x = InDirection.X, y = InDirection.Y, z = InDirection.Z;
FVector Ret = FVector(0, 0, 0);
// see http://msdn.microsoft.com/en-us/library/bb204881(v=vs.85).aspx
switch(CubemapFace)
{
case 0: Ret = FVector(+z, -y, -x); break;
case 1: Ret = FVector(-z, -y, +x); break;
case 2: Ret = FVector(+x, +z, +y); break;
case 3: Ret = FVector(+x, -z, -y); break;
case 4: Ret = FVector(+x, -y, +z); break;
case 5: Ret = FVector(-x, -y, -z); break;
default:
checkSlow(0);
}
// this makes it with the Unreal way (z and y are flipped)
return FVector(Ret.X, Ret.Z, Ret.Y);
}
// transform vector relative to the face to world space
static FVector TransformWorldToSideSpace(uint32 CubemapFace, FVector InDirection)
{
// undo Unreal way (z and y are flipped)
float x = InDirection.X, y = InDirection.Z, z = InDirection.Y;
FVector Ret = FVector(0, 0, 0);
// see http://msdn.microsoft.com/en-us/library/bb204881(v=vs.85).aspx
switch(CubemapFace)
{
case 0: Ret = FVector(-z, -y, +x); break;
case 1: Ret = FVector(+z, -y, -x); break;
case 2: Ret = FVector(+x, +z, +y); break;
case 3: Ret = FVector(+x, -z, -y); break;
case 4: Ret = FVector(+x, -y, +z); break;
case 5: Ret = FVector(-x, -y, -z); break;
default:
checkSlow(0);
}
return Ret;
}
static FVector ComputeSSCubeDirectionAtTexelCenter(uint32 x, uint32 y, float InvSideExtent)
{
// center of the texels
FVector DirectionSS((x + 0.5f) * InvSideExtent * 2 - 1, (y + 0.5f) * InvSideExtent * 2 - 1, 1);
DirectionSS.Normalize();
return DirectionSS;
}
static FVector ComputeWSCubeDirectionAtTexelCenter(uint32 CubemapFace, uint32 x, uint32 y, float InvSideExtent)
{
FVector DirectionSS = ComputeSSCubeDirectionAtTexelCenter(x, y, InvSideExtent);
FVector DirectionWS = TransformSideToWorldSpace(CubemapFace, DirectionSS);
return DirectionWS;
}
static uint32 ComputeLongLatCubemapExtents(const FImage& SrcImage, const uint32 MaxCubemapTextureResolution)
{
return FMath::Clamp(1U << FMath::FloorLog2(SrcImage.SizeX / 2), 32U, MaxCubemapTextureResolution);
}
void ITextureCompressorModule::GenerateBaseCubeMipFromLongitudeLatitude2D(FImage* OutMip, const FImage& SrcImage, const uint32 MaxCubemapTextureResolution, uint8 SourceEncodingOverride)
{
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.GenerateBaseCubeMipFromLongitudeLatitude2D);
FImage LongLatImage;
SrcImage.Linearize(SourceEncodingOverride, LongLatImage);
// TODO_TEXTURE: Expose target size to user.
uint32 Extent = ComputeLongLatCubemapExtents(LongLatImage, MaxCubemapTextureResolution);
float InvExtent = 1.0f / Extent;
OutMip->Init(Extent, Extent, SrcImage.NumSlices * 6, ERawImageFormat::RGBA32F, EGammaSpace::Linear);
for (int32 Slice = 0; Slice < SrcImage.NumSlices; ++Slice)
{
FImageViewLongLat LongLatView(LongLatImage, Slice);
for (uint32 Face = 0; Face < 6; ++Face)
{
FImageView2D MipView(*OutMip, Slice * 6 + Face);
for (uint32 y = 0; y < Extent; ++y)
{
for (uint32 x = 0; x < Extent; ++x)
{
FVector DirectionWS = ComputeWSCubeDirectionAtTexelCenter(Face, x, y, InvExtent);
MipView.Access(x, y) = LongLatView.LookupLongLat(DirectionWS);
}
}
}
}
}
class FTexelProcessor
{
public:
// @param InConeAxisSS - normalized, in side space
// @param TexelAreaArray - precomputed area of each texel for correct weighting
FTexelProcessor(const FVector& InConeAxisSS, float ConeAngle, const FLinearColor* InSideData, const float* InTexelAreaArray, uint32 InFullExtent)
: ConeAxisSS(InConeAxisSS)
, AccumulatedColor(0, 0, 0, 0)
, SideData(InSideData)
, TexelAreaArray(InTexelAreaArray)
, FullExtent(InFullExtent)
{
ConeAngleSin = sinf(ConeAngle);
ConeAngleCos = cosf(ConeAngle);
// *2 as the position is from -1 to 1
// / InFullExtent as x and y is in the range 0..InFullExtent-1
PositionToWorldScale = 2.0f / InFullExtent;
InvFullExtent = 1.0f / FullExtent;
// examples: 0 to diffuse convolution, 0.95f for glossy
DirDot = FMath::Min(FMath::Cos(ConeAngle), 0.9999f);
InvDirOneMinusDot = 1.0f / (1.0f - DirDot);
// precomputed sqrt(2.0f * 2.0f + 2.0f * 2.0f)
float Sqrt8 = 2.8284271f;
RadiusToWorldScale = Sqrt8 / (float)InFullExtent;
}
// @return true: yes, traverse deeper, false: not relevant
bool TestIfRelevant(uint32 x, uint32 y, uint32 LocalExtent) const
{
float HalfExtent = LocalExtent * 0.5f;
float U = (x + HalfExtent) * PositionToWorldScale - 1.0f;
float V = (y + HalfExtent) * PositionToWorldScale - 1.0f;
float SphereRadius = RadiusToWorldScale * LocalExtent;
FVector SpherePos(U, V, 1);
return FMath::SphereConeIntersection(SpherePos, SphereRadius, ConeAxisSS, ConeAngleSin, ConeAngleCos);
}
void Process(uint32 x, uint32 y)
{
const FLinearColor* In = &SideData[x + y * FullExtent];
FVector DirectionSS = ComputeSSCubeDirectionAtTexelCenter(x, y, InvFullExtent);
float DotValue = ConeAxisSS | DirectionSS;
if(DotValue > DirDot)
{
// 0..1, 0=at kernel border..1=at kernel center
float KernelWeight = 1.0f - (1.0f - DotValue) * InvDirOneMinusDot;
// apply smoothstep function (softer, less linear result)
KernelWeight = KernelWeight * KernelWeight * (3 - 2 * KernelWeight);
float AreaCompensation = TexelAreaArray[x + y * FullExtent];
// AreaCompensation would be need for correctness but seems it has a but
// as it looks much better (no seam) without, the effect is minor so it's deactivated for now.
// float Weight = KernelWeight * AreaCompensation;
float Weight = KernelWeight;
AccumulatedColor.R += Weight * In->R;
AccumulatedColor.G += Weight * In->G;
AccumulatedColor.B += Weight * In->B;
AccumulatedColor.A += Weight;
}
}
// normalized, in side space
FVector ConeAxisSS;
FLinearColor AccumulatedColor;
// cached for better performance
float ConeAngleSin;
float ConeAngleCos;
float PositionToWorldScale;
float RadiusToWorldScale;
float InvFullExtent;
// 0 to diffuse convolution, 0.95f for glossy
float DirDot;
float InvDirOneMinusDot;
/** [x + y * FullExtent] */
const FLinearColor* SideData;
const float* TexelAreaArray;
uint32 FullExtent;
};
template <class TVisitor>
void TCubemapSideRasterizer(TVisitor &TexelProcessor, int32 x, uint32 y, uint32 Extent)
{
if(Extent > 1)
{
if(!TexelProcessor.TestIfRelevant(x, y, Extent))
{
return;
}
Extent /= 2;
TCubemapSideRasterizer(TexelProcessor, x, y, Extent);
TCubemapSideRasterizer(TexelProcessor, x + Extent, y, Extent);
TCubemapSideRasterizer(TexelProcessor, x, y + Extent, Extent);
TCubemapSideRasterizer(TexelProcessor, x + Extent, y + Extent, Extent);
}
else
{
TexelProcessor.Process(x, y);
}
}
static FLinearColor IntegrateAngularArea(FImage& Image, FVector FilterDirectionWS, float ConeAngle, const float* TexelAreaArray)
{
// Alpha channel is used to renormalize later
FLinearColor ret(0, 0, 0, 0);
int32 Extent = Image.SizeX;
for(uint32 Face = 0; Face < 6; ++Face)
{
FImageView2D ImageView(Image, Face);
FVector FilterDirectionSS = TransformWorldToSideSpace(Face, FilterDirectionWS);
FTexelProcessor Processor(FilterDirectionSS, ConeAngle, &ImageView.Access(0,0), TexelAreaArray, Extent);
// recursively split the (0,0)-(Extent-1,Extent-1), tests for intersection and processes only colors inside
TCubemapSideRasterizer(Processor, 0, 0, Extent);
ret += Processor.AccumulatedColor;
}
if(ret.A != 0)
{
float Inv = 1.0f / ret.A;
ret.R *= Inv;
ret.G *= Inv;
ret.B *= Inv;
}
else
{
// should not happen
// checkSlow(0);
}
ret.A = 0;
return ret;
}
// @return 2 * computed triangle area
static inline float TriangleArea2_3D(FVector A, FVector B, FVector C)
{
return ((A-B) ^ (C-B)).Size();
}
static inline float ComputeTexelArea(uint32 x, uint32 y, float InvSideExtentMul2)
{
float fU = x * InvSideExtentMul2 - 1;
float fV = y * InvSideExtentMul2 - 1;
FVector CornerA = FVector(fU, fV, 1);
FVector CornerB = FVector(fU + InvSideExtentMul2, fV, 1);
FVector CornerC = FVector(fU, fV + InvSideExtentMul2, 1);
FVector CornerD = FVector(fU + InvSideExtentMul2, fV + InvSideExtentMul2, 1);
CornerA.Normalize();
CornerB.Normalize();
CornerC.Normalize();
CornerD.Normalize();
return TriangleArea2_3D(CornerA, CornerB, CornerC) + TriangleArea2_3D(CornerC, CornerB, CornerD) * 0.5f;
}
/**
* Generate a mip using angular filtering.
* @param DestMip - The filtered mip.
* @param SrcMip - The source mip which will be filtered.
* @param ConeAngle - The cone angle with which to filter.
*/
static void GenerateAngularFilteredMip(FImage* DestMip, FImage& SrcMip, float ConeAngle)
{
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.GenerateAngularFilteredMip);
int32 MipExtent = DestMip->SizeX;
float MipInvSideExtent = 1.0f / MipExtent;
TArray<float> TexelAreaArray;
TexelAreaArray.AddUninitialized(SrcMip.SizeX * SrcMip.SizeY);
// precompute the area size for one face (is the same for each face)
for(int32 y = 0; y < SrcMip.SizeY; ++y)
{
for(int32 x = 0; x < SrcMip.SizeX; ++x)
{
TexelAreaArray[x + y * SrcMip.SizeX] = ComputeTexelArea(x, y, MipInvSideExtent * 2);
}
}
// We start getting gains running threaded upwards of sizes >= 128
if (SrcMip.SizeX >= 128)
{
// Quick workaround: Do a thread per mip
struct FAsyncGenerateMipsPerFaceWorker : public FNonAbandonableTask
{
int32 Face;
FImage* DestMip;
int32 Extent;
float ConeAngle;
const float* TexelAreaArray;
FImage* SrcMip;
FAsyncGenerateMipsPerFaceWorker(int32 InFace, FImage* InDestMip, int32 InExtent, float InConeAngle, const float* InTexelAreaArray, FImage* InSrcMip) :
Face(InFace),
DestMip(InDestMip),
Extent(InExtent),
ConeAngle(InConeAngle),
TexelAreaArray(InTexelAreaArray),
SrcMip(InSrcMip)
{
}
void DoWork()
{
const float InvSideExtent = 1.0f / Extent;
FImageView2D DestMipView(*DestMip, Face);
for (int32 y = 0; y < Extent; ++y)
{
for (int32 x = 0; x < Extent; ++x)
{
FVector DirectionWS = ComputeWSCubeDirectionAtTexelCenter(Face, x, y, InvSideExtent);
DestMipView.Access(x, y) = IntegrateAngularArea(*SrcMip, DirectionWS, ConeAngle, TexelAreaArray);
}
}
}
FORCEINLINE TStatId GetStatId() const
{
RETURN_QUICK_DECLARE_CYCLE_STAT(FAsyncGenerateMipsPerFaceWorker, STATGROUP_ThreadPoolAsyncTasks);
}
};
typedef FAsyncTask<FAsyncGenerateMipsPerFaceWorker> FAsyncGenerateMipsPerFaceTask;
TIndirectArray<FAsyncGenerateMipsPerFaceTask> AsyncTasks;
for (int32 Face = 0; Face < 6; ++Face)
{
auto* AsyncTask = new FAsyncGenerateMipsPerFaceTask(Face, DestMip, MipExtent, ConeAngle, TexelAreaArray.GetData(), &SrcMip);
AsyncTasks.Add(AsyncTask);
AsyncTask->StartBackgroundTask();
}
for (int32 TaskIndex = 0; TaskIndex < AsyncTasks.Num(); ++TaskIndex)
{
auto& AsyncTask = AsyncTasks[TaskIndex];
AsyncTask.EnsureCompletion();
}
}
else
{
for (int32 Face = 0; Face < 6; ++Face)
{
FImageView2D DestMipView(*DestMip, Face);
for (int32 y = 0; y < MipExtent; ++y)
{
for (int32 x = 0; x < MipExtent; ++x)
{
FVector DirectionWS = ComputeWSCubeDirectionAtTexelCenter(Face, x, y, MipInvSideExtent);
DestMipView.Access(x, y) = IntegrateAngularArea(SrcMip, DirectionWS, ConeAngle, TexelAreaArray.GetData());
}
}
}
}
}
void ITextureCompressorModule::GenerateAngularFilteredMips(TArray<FImage>& InOutMipChain, int32 NumMips, uint32 DiffuseConvolveMipLevel)
{
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.GenerateAngularFilteredMips);
TArray<FImage> SrcMipChain;
Exchange(SrcMipChain, InOutMipChain);
InOutMipChain.Empty(NumMips);
// note: should work on cube arrays but currently does not
// GetMipGenSettings forces Angular off for anything but pure Cube classes (no arrays)
check( SrcMipChain[0].NumSlices == 6 );
// Generate simple averaged mips to accelerate angular filtering.
for (int32 MipIndex = SrcMipChain.Num(); MipIndex < NumMips; ++MipIndex)
{
FImage& BaseMip = SrcMipChain[MipIndex - 1];
int32 BaseExtent = BaseMip.SizeX;
int32 MipExtent = FMath::Max(BaseExtent >> 1, 1);
FImage* Mip = new(SrcMipChain) FImage(MipExtent, MipExtent, BaseMip.NumSlices, BaseMip.Format);
for(int32 Face = 0; Face < 6; ++Face)
{
FImageView2D BaseMipView(BaseMip, Face);
FImageView2D MipView(*Mip, Face);
for(int32 y = 0; y < MipExtent; ++y)
{
for(int32 x = 0; x < MipExtent; ++x)
{
FLinearColor Sum = (
BaseMipView.Access(x*2, y*2) +
BaseMipView.Access(x*2+1, y*2) +
BaseMipView.Access(x*2, y*2+1) +
BaseMipView.Access(x*2+1, y*2+1)
) * 0.25f;
MipView.Access(x,y) = Sum;
}
}
}
}
int32 Extent = 1 << (NumMips - 1);
int32 BaseExtent = Extent;
for (int32 i = 0; i < NumMips; ++i)
{
// 0:top mip 1:lowest mip = diffuse convolve
float NormalizedMipLevel = i / (float)(NumMips - DiffuseConvolveMipLevel);
float AdjustedMipLevel = NormalizedMipLevel * NumMips;
float NormalizedWidth = BaseExtent * FMath::Pow(2.0f, -AdjustedMipLevel);
float TexelSize = 1.0f / NormalizedWidth;
// 0.001f:sharp .. PI/2: diffuse convolve
// all lower mips are used for diffuse convolve
// above that the angle blends from sharp to diffuse convolved version
float ConeAngle = PI / 2.0f * TexelSize;
// restrict to reasonable range
ConeAngle = FMath::Clamp(ConeAngle, 0.002f, (float)PI / 2.0f);
UE_LOG(LogTextureCompressor, Verbose, TEXT("GenerateAngularFilteredMips %f %f %f %f %f"), NormalizedMipLevel, AdjustedMipLevel, NormalizedWidth, TexelSize, ConeAngle * 180 / PI);
// 0:normal, -1:4x faster, +1:4 times slower but more precise, -2, 2 ...
float QualityBias = 3.0f;
// defined to result in a area of 1.0f (NormalizedArea)
// optimized = 0.5f * FMath::Sqrt(1.0f / PI);
float SphereRadius = 0.28209478f;
float SegmentHeight = SphereRadius * (1.0f - FMath::Cos(ConeAngle));
// compute SphereSegmentArea
float AreaCoveredInNormalizedArea = 2 * PI * SphereRadius * SegmentHeight;
checkSlow(AreaCoveredInNormalizedArea <= 0.5f);
// unoptimized
// float FloatInputMip = FMath::Log2(FMath::Sqrt(AreaCoveredInNormalizedArea)) + InputMipCount - QualityBias;
// optimized
float FloatInputMip = 0.5f * FMath::Log2(AreaCoveredInNormalizedArea) + NumMips - QualityBias;
uint32 InputMip = FMath::Clamp(FMath::TruncToInt(FloatInputMip), 0, NumMips - 1);
FImage* Mip = new(InOutMipChain) FImage(Extent, Extent, 6, ERawImageFormat::RGBA32F);
GenerateAngularFilteredMip(Mip, SrcMipChain[InputMip], ConeAngle);
Extent = FMath::Max(Extent >> 1, 1);
}
}
static bool NeedAdjustImageColors(const FTextureBuildSettings& InBuildSettings)
{
const FColorAdjustmentParameters& InParams = InBuildSettings.ColorAdjustment;
return
!FMath::IsNearlyEqual(InParams.AdjustBrightness, 1.0f, (float)KINDA_SMALL_NUMBER) ||
!FMath::IsNearlyEqual(InParams.AdjustBrightnessCurve, 1.0f, (float)KINDA_SMALL_NUMBER) ||
!FMath::IsNearlyEqual(InParams.AdjustSaturation, 1.0f, (float)KINDA_SMALL_NUMBER) ||
!FMath::IsNearlyEqual(InParams.AdjustVibrance, 0.0f, (float)KINDA_SMALL_NUMBER) ||
!FMath::IsNearlyEqual(InParams.AdjustRGBCurve, 1.0f, (float)KINDA_SMALL_NUMBER) ||
!FMath::IsNearlyEqual(InParams.AdjustHue, 0.0f, (float)KINDA_SMALL_NUMBER) ||
!FMath::IsNearlyEqual(InParams.AdjustMinAlpha, 0.0f, (float)KINDA_SMALL_NUMBER) ||
!FMath::IsNearlyEqual(InParams.AdjustMaxAlpha, 1.0f, (float)KINDA_SMALL_NUMBER) ||
InBuildSettings.bChromaKeyTexture;
}
static inline void AdjustColors(FLinearColor * Colors,int64 Count,
const FTextureBuildSettings& InBuildSettings)
{
const FColorAdjustmentParameters& Params = InBuildSettings.ColorAdjustment;
// @todo Oodle : not the same checks as bAdjustNeeded outside
// but preserves legacy behavior
bool bAdjustBrightnessCurve = (!FMath::IsNearlyEqual(Params.AdjustBrightnessCurve, 1.0f, (float)KINDA_SMALL_NUMBER) && Params.AdjustBrightnessCurve != 0.0f);
bool bAdjustVibrance = (!FMath::IsNearlyZero(Params.AdjustVibrance, (float)KINDA_SMALL_NUMBER));
bool bAdjustRGBCurve = (!FMath::IsNearlyEqual(Params.AdjustRGBCurve, 1.0f, (float)KINDA_SMALL_NUMBER) && Params.AdjustRGBCurve != 0.0f);
bool bAdjustSaturation = ( Params.AdjustSaturation != 1.f || bAdjustVibrance );
bool bAdjustValue = ( Params.AdjustBrightness != 1.f ) || bAdjustBrightnessCurve;
float AdjustHue = Params.AdjustHue;
if ( AdjustHue != 0.f )
{
// Params.AdjustHue should be in [0,360] , make sure
if ( AdjustHue < 0.f || AdjustHue > 360.f )
{
AdjustHue = fmodf(AdjustHue, 360.0f);
if ( AdjustHue < 0.f )
{
AdjustHue += 360.f;
}
}
}
// BuildSettings.ChromaKeyColor is an FColor
FLinearColor ChromaKeyColor(InBuildSettings.ChromaKeyColor);
bool bHDRSource = InBuildSettings.bHDRSource;
bool bChromaKeyTexture = InBuildSettings.bChromaKeyTexture;
float ChromaKeyThreshold = InBuildSettings.ChromaKeyThreshold + SMALL_NUMBER;
for(int64 i=0;i<Count;i++)
{
FLinearColor OriginalColor = Colors[i];
#if 0
if ( ! bHDRSource )
{
// @todo Oodle: for non-HDR source ensure we are clamped as expected
// (can drift out of clamp due to previous processing)
// if you wind up even very slightly out of [0,1] range this function does bad things
// I think this probably should be done, but left disabled to preserve legacy behavior
OriginalColor.R = FMath::Clamp(OriginalColor.R, 0.0f, 1.f);
OriginalColor.G = FMath::Clamp(OriginalColor.G, 0.0f, 1.f);
OriginalColor.B = FMath::Clamp(OriginalColor.B, 0.0f, 1.f);
}
#endif
if (bChromaKeyTexture && (OriginalColor.Equals(ChromaKeyColor, ChromaKeyThreshold)))
{
OriginalColor = FLinearColor::Transparent;
//@todo Oodle: strange: no return? processing continues on the transparent color...
// this was likely unintentional
//Colors[i] = FLinearColor::Transparent;
//continue;
}
// NOTE: if OriginalColor has HDR/floats in it, this does not handle it well
// it implicitly discards negatives (and negatives cause color shifts)
// for values > 1 the clamp behavior is very strange
// Convert to HSV
FLinearColor HSVColor = OriginalColor.LinearRGBToHSV();
float& PixelHue = HSVColor.R;
float& PixelSaturation = HSVColor.G;
float& PixelValue = HSVColor.B;
float OriginalLuminance = PixelValue;
if ( bAdjustValue )
{
// Apply brightness adjustment
PixelValue *= Params.AdjustBrightness;
// Apply brightness power adjustment
if ( bAdjustBrightnessCurve )
{
// Raise HSV.V to the specified power
PixelValue = FMath::Pow(PixelValue, Params.AdjustBrightnessCurve);
}
// Clamp brightness if non-HDR
if (!bHDRSource)
{
PixelValue = FMath::Clamp(PixelValue, 0.0f, 1.0f);
}
}
if ( bAdjustSaturation )
{
// PixelSaturation is >= 0 but not <= 1
// because negative RGB can come into this function which gives Saturation > 1
// Apply "vibrance" adjustment
if ( bAdjustVibrance )
{
// note: AdjustVibrance is disabled for HDR source in the Texture UPROPERTIES
// (unclear why, this is no worse than anything else here on HDR)
// @todo Oodle : we'd like to just do the multiplies to make pow 5 but can't because it could change floats
const float SatRaisePow = 5.0f;
const float InvSatRaised = FMath::Pow(1.0f - PixelSaturation, SatRaisePow);
const float ClampedVibrance = FMath::Clamp(Params.AdjustVibrance, 0.0f, 1.0f);
const float HalfVibrance = ClampedVibrance * 0.5f;
const float SatProduct = HalfVibrance * InvSatRaised;
PixelSaturation += SatProduct;
}
// Apply saturation adjustment
PixelSaturation *= Params.AdjustSaturation;
PixelSaturation = FMath::Clamp(PixelSaturation, 0.0f, 1.0f);
}
// Apply hue adjustment
if ( AdjustHue != 0.f )
{
// PixelHue is [0,360) but AdjustHue is [0,360]
PixelHue += AdjustHue;
// Clamp HSV values
if ( PixelHue >= 360.f )
{
PixelHue -= 360.f;
}
}
// Convert back to a linear color
FLinearColor LinearColor = HSVColor.HSVToLinearRGB();
// Apply RGB curve adjustment (linear space)
if ( bAdjustRGBCurve )
{
LinearColor.R = FMath::Pow(LinearColor.R, Params.AdjustRGBCurve);
LinearColor.G = FMath::Pow(LinearColor.G, Params.AdjustRGBCurve);
LinearColor.B = FMath::Pow(LinearColor.B, Params.AdjustRGBCurve);
}
// Clamp HDR RGB channels to 1 or the original luminance (max original RGB channel value), whichever is greater
// @todo Oodle: this is a very odd thing to do
// clamping at OriginalLuminance if you do AdjustBrightness or AdjustBrightnessCurve ?
// that would keep values brighter than 1.f unchanged, but bring up lower ones to 1.f
// I question whether this should just be completely removed
if (bHDRSource)
{
LinearColor.R = FMath::Clamp(LinearColor.R, 0.0f, (OriginalLuminance > 1.0f ? OriginalLuminance : 1.0f));
LinearColor.G = FMath::Clamp(LinearColor.G, 0.0f, (OriginalLuminance > 1.0f ? OriginalLuminance : 1.0f));
LinearColor.B = FMath::Clamp(LinearColor.B, 0.0f, (OriginalLuminance > 1.0f ? OriginalLuminance : 1.0f));
}
// Remap the alpha channel
// @todo Oodle: clamp Original A in [0,1] ?
LinearColor.A = FMath::Lerp(Params.AdjustMinAlpha, Params.AdjustMaxAlpha, OriginalColor.A);
Colors[i] = LinearColor;
}
}
void ITextureCompressorModule::AdjustImageColors(FImage& Image, const FTextureBuildSettings& InBuildSettings)
{
const FColorAdjustmentParameters& InParams = InBuildSettings.ColorAdjustment;
check( Image.SizeX > 0 && Image.SizeY > 0 );
// @todo Oodle : this bAdjustNeeded is not checking the same conditions to enable these adjustments
// as is used inside the AdjustColors() routine
// this is how it was done in the past, so keep it the same to preserve legacy operation
// if possible in the future factor this Needed check out so it is shared code
bool bAdjustNeeded = NeedAdjustImageColors(InBuildSettings);
if ( bAdjustNeeded )
{
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.AdjustImageColors);
const int64 NumPixels = (int64)Image.SizeX * Image.SizeY * Image.NumSlices;
TArrayView64<FLinearColor> ImageColors = Image.AsRGBA32F();
int64 NumPixelsEachJob;
int32 NumJobs = ImageParallelForComputeNumJobsForPixels(NumPixelsEachJob,NumPixels);
// bForceSingleThread is set to true when:
// editor or cooker is loading as this is when the derived data cache is rebuilt as it will already be limited to a single thread
// and thus overhead of multithreading will simply make it slower
// @todo Oodle - this is done here and not in other similar ParallelFor places here. It should either be done everywhere or nowhere.
bool bForceSingleThread = GIsEditorLoadingPackage || GIsCookerLoadingPackage || IsInAsyncLoadingThread();
ParallelFor( TEXT("Texture.AdjustImageColorsFunc.PF"),NumJobs,1, [&](int32 Index)
{
int64 StartIndex = Index * NumPixelsEachJob;
int64 EndIndex = FMath::Min(StartIndex + NumPixelsEachJob, NumPixels);
FLinearColor * First = &ImageColors[StartIndex];
int64 Count = EndIndex-StartIndex;
AdjustColors(First,Count,InBuildSettings);
}
, (bForceSingleThread ? EParallelForFlags::ForceSingleThread : EParallelForFlags::None) );
}
}
/**
* Compute the alpha channel how BokehDOF needs it setup
*
* @param Image Image to adjust
*/
static void ComputeBokehAlpha(FImage& Image)
{
check( Image.SizeX > 0 && Image.SizeY > 0 );
const int32 NumPixels = Image.SizeX * Image.SizeY * Image.NumSlices;
TArrayView64<FLinearColor> ImageColors = Image.AsRGBA32F();
// compute LinearAverage
FLinearColor LinearAverage;
{
FLinearColor LinearSum(0, 0, 0, 0);
for( int32 CurPixelIndex = 0; CurPixelIndex < NumPixels; ++CurPixelIndex )
{
LinearSum += ImageColors[ CurPixelIndex ];
}
LinearAverage = LinearSum / (float)NumPixels;
}
FLinearColor Scale(1, 1, 1, 1);
// we want to normalize the image to have 0.5 as average luminance, this is assuming clamping doesn't happen (can happen when using a very small Bokeh shape)
{
float RGBLum = (LinearAverage.R + LinearAverage.G + LinearAverage.B) / 3.0f;
// ideally this would be 1 but then some pixels would need to be >1 which is not supported for the textureformat we want to use.
// The value affects the occlusion computation of the BokehDOF
const float LumGoal = 0.25f;
// clamp to avoid division by 0
Scale *= LumGoal / FMath::Max(RGBLum, 0.001f);
}
{
for( int32 CurPixelIndex = 0; CurPixelIndex < NumPixels; ++CurPixelIndex )
{
const FLinearColor OriginalColor = ImageColors[ CurPixelIndex ];
// Convert to a linear color
FLinearColor LinearColor = OriginalColor * Scale;
float RGBLum = (LinearColor.R + LinearColor.G + LinearColor.B) / 3.0f;
LinearColor.A = FMath::Clamp(RGBLum, 0.0f, 1.0f);
ImageColors[ CurPixelIndex ] = LinearColor;
}
}
}
/**
* Replicates the contents of the red channel to the green, blue, and alpha channels.
*/
static void ReplicateRedChannel( TArray<FImage>& InOutMipChain )
{
const uint32 MipCount = InOutMipChain.Num();
for ( uint32 MipIndex = 0; MipIndex < MipCount; ++MipIndex )
{
FImage& SrcMip = InOutMipChain[MipIndex];
FLinearColor* FirstColor = (&SrcMip.AsRGBA32F()[0]);
FLinearColor* LastColor = FirstColor + (SrcMip.SizeX * SrcMip.SizeY * SrcMip.NumSlices);
for ( FLinearColor* Color = FirstColor; Color < LastColor; ++Color )
{
*Color = FLinearColor( Color->R, Color->R, Color->R, Color->R );
}
}
}
/**
* Replicates the contents of the alpha channel to the red, green, and blue channels.
*/
static void ReplicateAlphaChannel( TArray<FImage>& InOutMipChain )
{
const uint32 MipCount = InOutMipChain.Num();
for ( uint32 MipIndex = 0; MipIndex < MipCount; ++MipIndex )
{
FImage& SrcMip = InOutMipChain[MipIndex];
FLinearColor* FirstColor = (&SrcMip.AsRGBA32F()[0]);
FLinearColor* LastColor = FirstColor + (SrcMip.SizeX * SrcMip.SizeY * SrcMip.NumSlices);
for ( FLinearColor* Color = FirstColor; Color < LastColor; ++Color )
{
*Color = FLinearColor( Color->A, Color->A, Color->A, Color->A );
}
}
}
/**
* Flips the contents of the green channel.
* @param InOutMipChain - The mip chain on which the green channel shall be flipped.
*/
static void FlipGreenChannel( FImage& Image )
{
FLinearColor* FirstColor = (&Image.AsRGBA32F()[0]);
FLinearColor* LastColor = FirstColor + (Image.SizeX * Image.SizeY * Image.NumSlices);
for ( FLinearColor* Color = FirstColor; Color < LastColor; ++Color )
{
Color->G = 1.0f - FMath::Clamp(Color->G, 0.0f, 1.0f);
}
}
/**
* Detects whether or not the image contains an alpha channel where at least one texel is != 255.
*/
static bool DetectAlphaChannel(const FImage& InImage)
{
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.DetectAlphaChannel);
// previous :
// "SMALL_NUMBER" is quite small, this provides almost no tolerance
// #define SMALL_NUMBER (1.e-8f)
//const float FloatNonOpaqueAlpha = 1.0f - SMALL_NUMBER;
//
// opaque alpha threshold where we'd quantize to < 255 in U8
// images with only alpha larger than this are treated as opaque
const float FloatNonOpaqueAlpha = 254.5f / 255.f; // the U8 alpha threshold
int64 NumPixels = (int64)InImage.SizeX * InImage.SizeY * InImage.NumSlices;
if ( InImage.Format == ERawImageFormat::BGRA8 )
{
TArrayView64<const FColor> SrcColorArray = InImage.AsBGRA8();
check( SrcColorArray.Num() == NumPixels );
const FColor * ColorPtr = &SrcColorArray[0];
const FColor * EndPtr = ColorPtr + SrcColorArray.Num();
for(;ColorPtr<EndPtr;++ColorPtr)
{
if ( ColorPtr->A != 255 )
{
return true;
}
}
}
else if ( InImage.Format == ERawImageFormat::RGBA32F )
{
TArrayView64<const FLinearColor> SrcColorArray = InImage.AsRGBA32F();
check( SrcColorArray.Num() == NumPixels );
const FLinearColor * ColorPtr = &SrcColorArray[0];
const FLinearColor * EndPtr = ColorPtr + SrcColorArray.Num();
for(;ColorPtr<EndPtr;++ColorPtr)
{
if (ColorPtr->A <= FloatNonOpaqueAlpha )
{
return true;
}
}
}
else if ( InImage.Format == ERawImageFormat::RGBA16 )
{
TArrayView64<const uint16> SrcChannelArray = InImage.AsRGBA16();
check( SrcChannelArray.Num() == NumPixels*4 );
const uint16 * ChannelPtr = &SrcChannelArray[0];
const uint16 * EndPtr = ChannelPtr + SrcChannelArray.Num();
for(;ChannelPtr<EndPtr;ChannelPtr += 4)
{
if ( ChannelPtr[3] != 0xFFFF )
{
return true;
}
}
}
else if ( InImage.Format == ERawImageFormat::RGBA16F )
{
TArrayView64<const FFloat16Color> SrcColorArray = InImage.AsRGBA16F();
check( SrcColorArray.Num() == NumPixels );
const FFloat16Color * ColorPtr = &SrcColorArray[0];
const FFloat16Color * EndPtr = ColorPtr + SrcColorArray.Num();
for(;ColorPtr<EndPtr;++ColorPtr)
{
// 16F closest to 1.0 is 0.99951172
// use the float tolerance here? or check exactly ?
//if ( ColorPtr->A.GetFloat() < 1.f )
// use the same FloatNonOpaqueAlpha tolerance for consistency ?
if ( ColorPtr->A.GetFloat() < FloatNonOpaqueAlpha )
{
return true;
}
}
}
else if ( InImage.Format == ERawImageFormat::G8 ||
InImage.Format == ERawImageFormat::BGRE8 ||
InImage.Format == ERawImageFormat::G16 ||
InImage.Format == ERawImageFormat::R16F )
{
// source image formats don't have alpha
}
else
{
// new format ?
check(0);
}
return false;
}
/** Calculate a scale per 4x4 block of each image, and apply it to the red/green channels. Store scale in the blue channel. */
static void ApplyYCoCgBlockScale(TArray<FImage>& InOutMipChain)
{
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.ApplyYCoCgBlockScale);
const uint32 MipCount = InOutMipChain.Num();
for (uint32 MipIndex = 0; MipIndex < MipCount; ++MipIndex)
{
FImage& SrcMip = InOutMipChain[MipIndex];
FLinearColor* FirstColor = (&SrcMip.AsRGBA32F()[0]);
int32 BlockWidthX = SrcMip.SizeX / 4;
int32 BlockWidthY = SrcMip.SizeY / 4;
for (int32 Slice = 0; Slice < SrcMip.NumSlices; ++Slice)
{
FLinearColor* SliceFirstColor = FirstColor + (SrcMip.SizeX * SrcMip.SizeY * Slice);
for (int32 Y = 0; Y < BlockWidthY; ++Y)
{
FLinearColor* RowFirstColor = SliceFirstColor + (Y * 4 * SrcMip.SizeY);
for (int32 X = 0; X < BlockWidthX; ++X)
{
FLinearColor* BlockFirstColor = RowFirstColor + (X * 4);
// Iterate block to find MaxComponent
float MaxComponent = 0.f;
for (int32 BlockY = 0; BlockY < 4; ++BlockY)
{
FLinearColor* Color = BlockFirstColor + (BlockY * SrcMip.SizeY);
for (int32 BlockX = 0; BlockX < 4; ++BlockX, ++Color)
{
MaxComponent = FMath::Max(FMath::Abs(Color->R - 128.f / 255.f), MaxComponent);
MaxComponent = FMath::Max(FMath::Abs(Color->G - 128.f / 255.f), MaxComponent);
}
}
const float Scale = (MaxComponent < 32.f / 255.f) ? 4.f : (MaxComponent < 64.f / 255.f) ? 2.f : 1.f;
const float OutB = (Scale - 1.f) * 8.f / 255.f;
// Iterate block to modify for scale
for (int32 BlockY = 0; BlockY < 4; ++BlockY)
{
FLinearColor* Color = BlockFirstColor + (BlockY * SrcMip.SizeY);
for (int32 BlockX = 0; BlockX < 4; ++BlockX, ++Color)
{
const float OutR = (Color->R - 128.f / 255.f) * Scale + 128.f / 255.f;
const float OutG = (Color->G - 128.f / 255.f) * Scale + 128.f / 255.f;
*Color = FLinearColor(OutR, OutG, OutB, Color->A);
}
}
}
}
}
}
}
static float RoughnessToSpecularPower(float Roughness)
{
float Div = FMath::Pow(Roughness, 4);
// Roughness of 0 should result in a high specular power
float MaxSpecPower = 10000000000.0f;
Div = FMath::Max(Div, 2.0f / (MaxSpecPower + 2.0f));
return 2.0f / Div - 2.0f;
}
static float SpecularPowerToRoughness(float SpecularPower)
{
float Out = FMath::Pow( SpecularPower * 0.5f + 1.0f, -0.25f );
return Out;
}
// @param CompositeTextureMode original type ECompositeTextureMode
static void ApplyCompositeTexture(FImage& RoughnessSourceMips, const FImage& NormalSourceMips, uint8 CompositeTextureMode, float CompositePower)
{
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.ApplyCompositeTexture);
check(RoughnessSourceMips.SizeX == NormalSourceMips.SizeX);
check(RoughnessSourceMips.SizeY == NormalSourceMips.SizeY);
FLinearColor* FirstColor = (&RoughnessSourceMips.AsRGBA32F()[0]);
const FLinearColor* NormalColors = (&NormalSourceMips.AsRGBA32F()[0]);
int64 Count = (int64) RoughnessSourceMips.SizeX * RoughnessSourceMips.SizeY * RoughnessSourceMips.NumSlices;
float* TargetValuePtr;
switch((ECompositeTextureMode)CompositeTextureMode)
{
case CTM_NormalRoughnessToRed:
TargetValuePtr = &FirstColor->R;
break;
case CTM_NormalRoughnessToGreen:
TargetValuePtr = &FirstColor->G;
break;
case CTM_NormalRoughnessToBlue:
TargetValuePtr = &FirstColor->B;
break;
case CTM_NormalRoughnessToAlpha:
TargetValuePtr = &FirstColor->A;
break;
default:
UE_LOG(LogTextureCompressor, Error, TEXT("Invalid CompositeTextureMode"));
return;
}
for ( int64 i=0; i<Count; i++ )
{
const FLinearColor & NormalColor = NormalColors[i];
FVector3f Normal = FVector3f(NormalColor.R * 2.0f - 1.0f, NormalColor.G * 2.0f - 1.0f, NormalColor.B * 2.0f - 1.0f);
// Toksvig estimation of variance
float LengthN = FMath::Min( Normal.Size(), 1.0f );
float Variance = ( 1.0f - LengthN ) / LengthN;
Variance = FMath::Max( 0.0f, Variance - 0.00004f );
Variance *= CompositePower;
float Roughness = TargetValuePtr[i*4];
#if 0
float Power = RoughnessToSpecularPower( Roughness );
Power = Power / ( 1.0f + Variance * Power );
Roughness = SpecularPowerToRoughness( Power );
#else
// Refactored above to avoid divide by zero
float a = Roughness * Roughness;
float a2 = a * a;
float B = 2.0f * Variance * (a2 - 1.0f);
a2 = ( B - a2 ) / ( B - 1.0f );
Roughness = FMath::Pow( a2, 0.25f );
#endif
TargetValuePtr[i*4] = Roughness;
}
}
/*------------------------------------------------------------------------------
Image Compression.
------------------------------------------------------------------------------*/
// compress mip-maps in InMipChain and add mips to Texture, might alter the source content
static bool CompressMipChain(
const ITextureFormat* TextureFormat,
const TArray<FImage>& MipChain,
const FTextureBuildSettings& Settings,
const bool bImageHasAlphaChannel,
FStringView DebugTexturePathName,
TArray<FCompressedImage2D>& OutMips,
uint32& OutNumMipsInTail,
uint32& OutExtData)
{
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.CompressMipChain)
// now call the Ex version now that we have the proper MipChain
const FTextureFormatCompressorCaps CompressorCaps = TextureFormat->GetFormatCapabilitiesEx(Settings, MipChain.Num(), MipChain[0], bImageHasAlphaChannel);
OutNumMipsInTail = CompressorCaps.NumMipsInTail;
OutExtData = CompressorCaps.ExtData;
int32 MipCount = MipChain.Num();
check(MipCount >= (int32)CompressorCaps.NumMipsInTail);
// This number was too small (128) for current hardware and caused too many
// context switch for work taking < 1ms. Bump the value for 2020 CPUs.
const int32 MinAsyncCompressionSize = 512;
const bool bAllowParallelBuild = TextureFormat->AllowParallelBuild();
bool bCompressionSucceeded = true;
// Mip tail is when the last few mips get grouped together in the hardware layout.
// Treat not having a mip tail as having a mip tail with 1 mip in it, which is
// equivalent and lets us simplify the logic.
int32 FirstMipTailIndex = MipCount - 1;
int32 MipTailCount = 1;
if (CompressorCaps.NumMipsInTail > 1)
{
MipTailCount = CompressorCaps.NumMipsInTail;
FirstMipTailIndex = MipCount - MipTailCount;
}
uint32 StartCycles = FPlatformTime::Cycles();
// Set up one task for the base mip, one task for everything after. Since each mip level
// has 4x the pixels as the one below it (8x for volumes), work for mip levels is highly
// unbalanced and there's not much use spawning extra tasks past that: for a 2D texture,
// the entire tail after the base mip (all remaining mips combined) has 1/3 the number of
// pixels the base mip does.
OutMips.Empty(MipCount);
OutMips.AddDefaulted(MipCount);
auto ProcessMips =
[&TextureFormat, &MipChain, &OutMips, FirstMipTailIndex, MipTailCount, &CompressorCaps, &Settings, &DebugTexturePathName, bImageHasAlphaChannel](int32 MipBegin, int32 MipEnd)
{
bool bSuccess = true;
for (int32 MipIndex = MipBegin; MipIndex < MipEnd; ++MipIndex)
{
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.CompressImage);
bSuccess = bSuccess && TextureFormat->CompressImageEx(
&MipChain[MipIndex],
MipIndex == FirstMipTailIndex ? MipTailCount : 1, // number of mips pointed to by SrcMip
Settings,
DebugTexturePathName,
bImageHasAlphaChannel,
CompressorCaps.ExtData,
OutMips[MipIndex]
);
}
return bSuccess;
};
if (bAllowParallelBuild &&
FirstMipTailIndex > 0 &&
FMath::Min(MipChain[0].SizeX, MipChain[0].SizeY) >= MinAsyncCompressionSize)
{
// Spawn async job to compress all mips below base
auto AsyncTask = UE::Tasks::Launch(TEXT("Texture.CompressLowerMips"),
[&ProcessMips, FirstMipTailIndex]()
{
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.CompressLowerMips);
return ProcessMips(1, FirstMipTailIndex + 1);
},
LowLevelTasks::ETaskPriority::BackgroundNormal
);
// Compress base mip on this thread, join with async compress of other mips
bCompressionSucceeded = ProcessMips(0, 1);
bCompressionSucceeded &= AsyncTask.GetResult();
}
else
{
// Compress all mips at once on this thread
bCompressionSucceeded = ProcessMips(0, FirstMipTailIndex + 1);
}
for (int32 MipIndex = FirstMipTailIndex + 1; MipIndex < MipCount; ++MipIndex)
{
FCompressedImage2D& PrevMip = OutMips[MipIndex - 1];
FCompressedImage2D& DestMip = OutMips[MipIndex];
DestMip.SizeX = FMath::Max(1, PrevMip.SizeX >> 1);
DestMip.SizeY = FMath::Max(1, PrevMip.SizeY >> 1);
DestMip.SizeZ = Settings.bVolume ? FMath::Max(1, PrevMip.SizeZ >> 1) : PrevMip.SizeZ;
DestMip.PixelFormat = PrevMip.PixelFormat;
}
if (!bCompressionSucceeded)
{
OutMips.Empty();
}
uint32 EndCycles = FPlatformTime::Cycles();
UE_LOG(LogTextureCompressor,Verbose,TEXT("Compressed %dx%dx%d %s in %fms"),
MipChain[0].SizeX,
MipChain[0].SizeY,
MipChain[0].NumSlices,
*Settings.TextureFormatName.ToString(),
FPlatformTime::ToMilliseconds( EndCycles-StartCycles )
);
return bCompressionSucceeded;
}
// only useful for normal maps, fixed bad input (denormalized normals) and improved quality (quantization artifacts)
static void NormalizeMip(FImage& InOutMip)
{
const uint32 NumPixels = InOutMip.SizeX * InOutMip.SizeY * InOutMip.NumSlices;
TArrayView64<FLinearColor> ImageColors = InOutMip.AsRGBA32F();
for(uint32 CurPixelIndex = 0; CurPixelIndex < NumPixels; ++CurPixelIndex)
{
FLinearColor& Color = ImageColors[CurPixelIndex];
FVector Normal = FVector(Color.R * 2.0f - 1.0f, Color.G * 2.0f - 1.0f, Color.B * 2.0f - 1.0f);
Normal = Normal.GetSafeNormal();
Color = FLinearColor(Normal.X * 0.5f + 0.5f, Normal.Y * 0.5f + 0.5f, Normal.Z * 0.5f + 0.5f, Color.A);
}
}
/**
* Texture compression module
*/
class FTextureCompressorModule : public ITextureCompressorModule
{
public:
FTextureCompressorModule()
{
}
virtual bool BuildTexture(
const TArray<FImage>& SourceMips,
const TArray<FImage>& AssociatedNormalSourceMips,
const FTextureBuildSettings& BuildSettings,
FStringView DebugTexturePathName,
TArray<FCompressedImage2D>& OutTextureMips,
uint32& OutNumMipsInTail,
uint32& OutExtData
)
{
//TRACE_CPUPROFILER_EVENT_SCOPE(Texture.BuildTexture);
const ITextureFormat* TextureFormat = nullptr;
ITextureFormatManagerModule* TFM = GetTextureFormatManager();
if (TFM)
{
TextureFormat = TFM->FindTextureFormat(BuildSettings.TextureFormatName);
}
if (TextureFormat == nullptr)
{
UE_LOG(LogTextureCompressor, Warning,
TEXT("Failed to find compressor for texture format '%s'."),
*BuildSettings.TextureFormatName.ToString()
);
return false;
}
// @todo Oodle: option to dump the Source image here
// we have dump in TextureFormatOodle for the after-processing (before encoding) image
// get a dump spot for before-processing as well
#if 0
// @todo Oodle : use or remove me
// experimental : detect if alpha is wanted in the mip filter process
bool bAlpha_Before = false;
bool bAlpha_Programmatic = false;
if ( ! BuildSettings.bForceNoAlphaChannel && ! BuildSettings.bForceAlphaChannel )
{
// at this point SourceMips is still in original format (eg. BGRA8 not yet promoted to linear float)
// bAlpha_Before can be accelerated from the source image in many cases (if it was 3-channel RGB source)
bAlpha_Before = DetectAlphaChannel(SourceMips[0]);
// can mip processing add alpha ?
// does not gaurantee it definitely does add alpha, it just might
bAlpha_Programmatic =
BuildSettings.bComputeBokehAlpha ||
BuildSettings.bReplicateRed ||
BuildSettings.bChromaKeyTexture ||
( BuildSettings.CompositeTextureMode == CTM_NormalRoughnessToAlpha && AssociatedNormalSourceMips.Num() > 0 );
// (note bLongLatCubemap skips these processings, may be wrong)
}
// if bFilterAlpha is off, we can make mips in RGB 3-channel and skip A processing
bool bFilterAlpha = (! BuildSettings.bForceNoAlphaChannel) && ( BuildSettings.bForceAlphaChannel || bAlpha_Before || bAlpha_Programmatic );
#endif
TArray<FImage> IntermediateMipChain;
// we can't use the Ex version here because it needs an FImage, which needs BuildTextureMips to be called
const FTextureFormatCompressorCaps CompressorCaps = TextureFormat->GetFormatCapabilities();
// allow to leave texture in sRGB in case compressor accepts other than non-F32 input source
// otherwise linearizing will force format to be RGBA32F
const bool bNeedLinearize = !TextureFormat->CanAcceptNonF32Source() || AssociatedNormalSourceMips.Num() != 0;
if (!BuildTextureMips(SourceMips, BuildSettings, CompressorCaps, bNeedLinearize, IntermediateMipChain))
{
return false;
}
// apply roughness adjustment depending on normal map variation
if (AssociatedNormalSourceMips.Num())
{
// check AssociatedNormalSourceMips.Format;
// ECompositeTextureMode is only NormalRoughness
// composite texture should be a normal map
TArray<FImage> IntermediateAssociatedNormalSourceMipChain;
FTextureBuildSettings DefaultSettings;
// apply a smooth Gaussian filter to the top level of the normal map
// the original comment says :
// "helps to reduce aliasing further"
DefaultSettings.MipSharpening = -3.5f;
DefaultSettings.SharpenMipKernelSize = 6;
DefaultSettings.bApplyKernelToTopMip = true;
// important to make accurate computation with normal length
DefaultSettings.bRenormalizeTopMip = true;
// use new mip filter setting from build settings
DefaultSettings.bUseNewMipFilter = BuildSettings.bUseNewMipFilter;
// @todo Oodle : filtering the normal map then computing roughness is fundamentally wrong
// we should instead compute the roughness scalar first on the original normap map
// then filter on the roughness scalar
if (!BuildTextureMips(AssociatedNormalSourceMips, DefaultSettings, CompressorCaps, true, IntermediateAssociatedNormalSourceMipChain))
{
UE_LOG(LogTextureCompressor, Warning, TEXT("Failed to generate texture mips for composite texture"));
}
if (!ApplyCompositeTexture(IntermediateMipChain, IntermediateAssociatedNormalSourceMipChain, BuildSettings.CompositeTextureMode, BuildSettings.CompositePower))
{
UE_LOG(LogTextureCompressor, Warning, TEXT("Failed to apply composite texture"));
}
}
// DetectAlphaChannel on the top mip of the generated mip chain
// it is now always Linear F32
// BuildSettings could have programatically introduced alpha that was not in the source
// note the order of operations in bForceAlphaChannel and bForceNoAlphaChannel (ambiguity if both are on)
const bool bImageHasAlphaChannel = !BuildSettings.bForceNoAlphaChannel && (BuildSettings.bForceAlphaChannel || DetectAlphaChannel(IntermediateMipChain[0]));
#if 0
// @todo Oodle : experimental : verify bFilterAlpha was right
// if bAlpha_Programmatic, we have to recheck if alpha got made or not
check( bImageHasAlphaChannel == bAlpha_Before || bAlpha_Programmatic );
// if bFilterAlpha is off, we should not have alpha out
check( bFilterAlpha || !bImageHasAlphaChannel );
#endif
// Set the correct biased texture size so that the compressor understands the original source image size
// This is requires for platforms that may need to tile based on the original source texture size
BuildSettings.TopMipSize.X = IntermediateMipChain[0].SizeX;
BuildSettings.TopMipSize.Y = IntermediateMipChain[0].SizeY;
BuildSettings.VolumeSizeZ = BuildSettings.bVolume ? IntermediateMipChain[0].NumSlices : 1;
if (BuildSettings.bTextureArray)
{
if (BuildSettings.bCubemap)
{
BuildSettings.ArraySlices = IntermediateMipChain[0].NumSlices / 6;
}
else
{
BuildSettings.ArraySlices = IntermediateMipChain[0].NumSlices;
}
}
else
{
BuildSettings.ArraySlices = 1;
}
return CompressMipChain(TextureFormat, IntermediateMipChain, BuildSettings, bImageHasAlphaChannel, DebugTexturePathName,
OutTextureMips, OutNumMipsInTail, OutExtData);
}
// IModuleInterface implementation.
void StartupModule()
{
}
void ShutdownModule()
{
}
private:
bool BuildTextureMips(
const TArray<FImage>& InSourceMipChain,
const FTextureBuildSettings& BuildSettings,
const FTextureFormatCompressorCaps& CompressorCaps,
const bool bNeedLinearize,
TArray<FImage>& OutMipChain)
{
TRACE_CPUPROFILER_EVENT_SCOPE(Texture.BuildTextureMips);
check(InSourceMipChain.Num() > 0);
check(InSourceMipChain[0].SizeX > 0 && InSourceMipChain[0].SizeY > 0 && InSourceMipChain[0].NumSlices > 0);
// Identify long-lat cubemaps.
const bool bLongLatCubemap = BuildSettings.bLongLatSource;
if (BuildSettings.bCubemap && !bLongLatCubemap)
{
if (BuildSettings.bTextureArray && (InSourceMipChain[0].NumSlices % 6) != 0)
{
// Cube array must have multiple of 6 slices
return false;
}
if (!BuildSettings.bTextureArray && InSourceMipChain[0].NumSlices != 6)
{
// Non-array cube must have exactly 6 slices
return false;
}
}
// handling of bLongLatCubemap seems overly complicated
// what it should do is convert it right at the start here
// then treat it as a standard cubemap below, no special cases
// but that will change output :(
// pSourceMips will track the current FImages we consider to be "source"
const TArray<FImage> * pSourceMips = &InSourceMipChain;
// first pad up to pow2 if requested
ETexturePowerOfTwoSetting::Type PowerOfTwoMode = (ETexturePowerOfTwoSetting::Type) BuildSettings.PowerOfTwoMode;
// if bPadOrStretchTextureis done, PaddedSourceMips is filled with a new image
TArray<FImage> PaddedSourceMips;
if ( PowerOfTwoMode != ETexturePowerOfTwoSetting::None )
{
const FImage& FirstSourceMipImage = (*pSourceMips)[0];
int32 TargetTextureSizeX = FirstSourceMipImage.SizeX;
int32 TargetTextureSizeY = FirstSourceMipImage.SizeY;
int32 TargetTextureSizeZ = BuildSettings.bVolume ? FirstSourceMipImage.NumSlices : 1; // Only used for volume texture.
const int32 PowerOfTwoTextureSizeX = FMath::RoundUpToPowerOfTwo(TargetTextureSizeX);
const int32 PowerOfTwoTextureSizeY = FMath::RoundUpToPowerOfTwo(TargetTextureSizeY);
const int32 PowerOfTwoTextureSizeZ = FMath::RoundUpToPowerOfTwo(TargetTextureSizeZ);
switch (PowerOfTwoMode)
{
// None should not get here
case ETexturePowerOfTwoSetting::PadToPowerOfTwo:
TargetTextureSizeX = PowerOfTwoTextureSizeX;
TargetTextureSizeY = PowerOfTwoTextureSizeY;
TargetTextureSizeZ = PowerOfTwoTextureSizeZ;
break;
case ETexturePowerOfTwoSetting::PadToSquarePowerOfTwo:
TargetTextureSizeX = TargetTextureSizeY = TargetTextureSizeZ =
FMath::Max3<int32>(PowerOfTwoTextureSizeX, PowerOfTwoTextureSizeY, PowerOfTwoTextureSizeZ);
break;
default:
checkf(false, TEXT("Unknown entry in ETexturePowerOfTwoSetting::Type"));
break;
}
bool bPadOrStretchTexture =
(TargetTextureSizeX != FirstSourceMipImage.SizeX) ||
(TargetTextureSizeY != FirstSourceMipImage.SizeY) ||
( BuildSettings.bVolume && TargetTextureSizeZ != FirstSourceMipImage.NumSlices );
if (bPadOrStretchTexture)
{
if (BuildSettings.MipGenSettings == TMGS_LeaveExistingMips)
{
// pad+leave existing is broken
UE_LOG(LogTextureCompressor, Error, TEXT("Texture padded to pow2 + LeaveExistingMips forbidden"));
return false;
}
if ( bLongLatCubemap )
{
UE_LOG(LogTextureCompressor, Warning, TEXT("PadPow2 + LongLat cubemap doesn't work, continuing.."));
}
// Want to stretch or pad the texture
bool bSuitableFormat = FirstSourceMipImage.Format == ERawImageFormat::RGBA32F;
FImage Temp;
if (!bSuitableFormat)
{
// convert to RGBA32F
FirstSourceMipImage.CopyTo(Temp, ERawImageFormat::RGBA32F, EGammaSpace::Linear);
}
// space for one source mip and one destination mip
const FImage& SourceImage = bSuitableFormat ? FirstSourceMipImage : Temp;
FImage& TargetImage = *new (PaddedSourceMips) FImage(TargetTextureSizeX, TargetTextureSizeY, BuildSettings.bVolume ? TargetTextureSizeZ : SourceImage.NumSlices, SourceImage.Format);
FLinearColor FillColor = BuildSettings.PaddingColor;
FLinearColor* TargetPtr = (FLinearColor*)TargetImage.RawData.GetData();
FLinearColor* SourcePtr = (FLinearColor*)SourceImage.RawData.GetData();
check(SourceImage.GetBytesPerPixel() == sizeof(FLinearColor));
check(TargetImage.GetBytesPerPixel() == sizeof(FLinearColor));
const int32 SourceBytesPerLine = SourceImage.SizeX * SourceImage.GetBytesPerPixel();
const int32 DestBytesPerLine = TargetImage.SizeX * TargetImage.GetBytesPerPixel();
for (int32 SliceIndex = 0; SliceIndex < SourceImage.NumSlices; ++SliceIndex)
{
for (int32 Y = 0; Y < TargetTextureSizeY; ++Y)
{
int32 XStart = 0;
if (Y < SourceImage.SizeY)
{
XStart = SourceImage.SizeX;
FMemory::Memcpy(TargetPtr, SourcePtr, SourceImage.SizeX * sizeof(FLinearColor));
SourcePtr += SourceImage.SizeX;
TargetPtr += SourceImage.SizeX;
}
for (int32 XPad = XStart; XPad < TargetImage.SizeX; ++XPad)
{
*TargetPtr++ = FillColor;
}
}
}
// Pad new slices for volume texture
for (int32 SliceIndex = SourceImage.NumSlices; SliceIndex < TargetImage.NumSlices; ++SliceIndex)
{
for (int32 Y = 0; Y < TargetImage.SizeY; ++Y)
{
for (int32 X = 0; X< TargetImage.SizeX; ++X)
{
*TargetPtr++ = FillColor;
}
}
}
// change pSourceMips to point at the one padded image we made
pSourceMips = &PaddedSourceMips;
}
}
// now pow2 pad is done
// find a starting source that meets MaxTextureResolution limit
int32 StartMip = 0;
TArray<FImage> BuildSourceImageMips;
if ( ! bLongLatCubemap )
{
int32 NumSourceMips = (BuildSettings.MipGenSettings == TMGS_LeaveExistingMips) ? pSourceMips->Num() : 1;
int64 MaxTextureResolution = BuildSettings.MaxTextureResolution;
// note that "LODBias" is very similar to MaxTextureResolution
// but for LODBias we go ahead and make all the mips here
// and then just don't serialize the top ones in TextureDerivedData
// (LODBias is not actually LOD Bias, it means discard top N mips)
// step through source mips to find one that meets MaxTextureResolution
while( StartMip < NumSourceMips && (
(*pSourceMips)[StartMip].SizeX > MaxTextureResolution ||
(*pSourceMips)[StartMip].SizeY > MaxTextureResolution ) )
{
StartMip++;
}
if ( StartMip == NumSourceMips )
{
if (BuildSettings.MipGenSettings == TMGS_LeaveExistingMips)
{
UE_LOG(LogTextureCompressor, Error, TEXT("LeaveExistingMips no mip that fits max dimension (%d)."),(int)MaxTextureResolution);
return false;
}
// currently only makes mips if you only had 1 source mip :
check(NumSourceMips == 1);
// bLongLatCubemap should not get here because cube size is made from MaxTextureSize
check( ! bLongLatCubemap );
// the source is larger than the compressor allows and no mip image exists to act as a smaller source.
// We must generate a suitable source image:
const FImage& BaseImage = pSourceMips->Last();
bool bSuitableFormat = BaseImage.Format == ERawImageFormat::RGBA32F;
check( MaxTextureResolution > 0 );
check( BaseImage.SizeX > MaxTextureResolution ||
BaseImage.SizeY > MaxTextureResolution );
FImage Temp;
if (!bSuitableFormat)
{
// convert to RGBA32F
BaseImage.CopyTo(Temp, ERawImageFormat::RGBA32F, EGammaSpace::Linear);
}
UE_LOG(LogTextureCompressor, Verbose,
TEXT("Source image %dx%d too large for compressors max dimension (%d). Resizing."),
BaseImage.SizeX,
BaseImage.SizeY,
BuildSettings.MaxTextureResolution
);
// make sure BuildSourceImageMips doesn't reallocate :
constexpr int BuildSourceImageMipsMaxCount = 16;
BuildSourceImageMips.Empty(BuildSourceImageMipsMaxCount);
// Max Texture Size resizing happens here :
// note we do not check for TMGS_Angular here
GenerateMipChain(BuildSettings, bSuitableFormat ? BaseImage : Temp, BuildSourceImageMips, 1);
while( BuildSourceImageMips.Last().SizeX > MaxTextureResolution ||
BuildSourceImageMips.Last().SizeY > MaxTextureResolution )
{
// note: now making mips one by one, rather than N in one call
// this is not exactly the same if AlphaCoverage processing is on
check( BuildSourceImageMips.Num() < BuildSourceImageMipsMaxCount );
GenerateMipChain(BuildSettings, BuildSourceImageMips.Last(), BuildSourceImageMips, 1);
}
check( BuildSourceImageMips.Last().SizeX <= MaxTextureResolution &&
BuildSourceImageMips.Last().SizeY <= MaxTextureResolution );
check( BuildSourceImageMips.Last().SizeX*2 > MaxTextureResolution ||
BuildSourceImageMips.Last().SizeY*2 > MaxTextureResolution );
// change pSourceMips to point at the mip chain we made
pSourceMips = &BuildSourceImageMips;
StartMip = BuildSourceImageMips.Num() - 1;
// [StartMip] will now references BuildSourceImageMips.Last()
}
}
// now shrinking to MaxTextureResolution is done, figure out which mips to use or make
// Copy over base mip and any LeaveExisting, from SourceMips , starting at StartMip
int32 CopyCount = pSourceMips->Num() - StartMip;
check( CopyCount > 0 );
int32 NumOutputMips;
if ( BuildSettings.MipGenSettings == TMGS_NoMipmaps )
{
NumOutputMips = 1;
CopyCount = 1;
}
else if ( BuildSettings.MipGenSettings == TMGS_LeaveExistingMips )
{
// only output what we can copy, generate none
NumOutputMips = CopyCount;
}
else
{
const FImage & TopMip = (*pSourceMips)[StartMip];
int32 TopMipSizeZ = BuildSettings.bVolume ? TopMip.NumSlices : 1;
// NumOutputMips is the number of mips that would be made if you made a full mip chain
// eg. 256 makes 9 mips , 300 also makes 9 mips
NumOutputMips = 1 + FMath::FloorLog2(
bLongLatCubemap ?
ComputeLongLatCubemapExtents(TopMip, BuildSettings.MaxTextureResolution) :
FMath::Max3(TopMip.SizeX, TopMip.SizeY, TopMipSizeZ) );
// unless LeaveExistingMips, we only copy 1
// (in theory we could copy some existing and generate the rest, but that's not done currently)
// (intentionally so, artists use this to limit mipping down)
CopyCount = 1;
}
// we will output NumOutputMips
OutMipChain.Empty(NumOutputMips);
int32 GenerateCount = NumOutputMips - CopyCount;
check( GenerateCount >= 0 );
// avoid converting to RGBA32F linear format if there's no need for any extra processing of pixels
// image will be left in BGRA8 format if possible
const bool bNeedAdjustImageColors = NeedAdjustImageColors(BuildSettings);
const bool bLinearize = bNeedLinearize || (GenerateCount > 0) || BuildSettings.bRenormalizeTopMip || (BuildSettings.Downscale > 1.f)
|| BuildSettings.bHasColorSpaceDefinition || BuildSettings.bComputeBokehAlpha || BuildSettings.bFlipGreenChannel
|| BuildSettings.bReplicateRed || BuildSettings.bReplicateAlpha || BuildSettings.bApplyYCoCgBlockScale
|| BuildSettings.SourceEncodingOverride != 0 || bNeedAdjustImageColors;
for (int32 MipIndex = StartMip; MipIndex < StartMip + CopyCount; ++MipIndex)
{
const FImage& Image = (*pSourceMips)[MipIndex];
// copy mips over + processing
// this is a code dupe of the processing done in GenerateMipChain
// create base for the mip chain
FImage* Mip = new(OutMipChain) FImage();
if (bLongLatCubemap)
{
// Generate the base mip from the long-lat source image.
GenerateBaseCubeMipFromLongitudeLatitude2D(Mip, Image, BuildSettings.MaxTextureResolution, BuildSettings.SourceEncodingOverride);
check( CopyCount == 1 );
// note the break here skips other adjustments:
break;
}
else
{
// copy base source content to the base of the mip chain
if(BuildSettings.bApplyKernelToTopMip)
{
FImage Temp;
Image.Linearize(BuildSettings.SourceEncodingOverride, Temp);
if(BuildSettings.bRenormalizeTopMip)
{
NormalizeMip(Temp);
}
GenerateTopMip(Temp, *Mip, BuildSettings);
}
else
{
if (bLinearize)
{
Image.Linearize(BuildSettings.SourceEncodingOverride, *Mip);
if (BuildSettings.bRenormalizeTopMip)
{
NormalizeMip(*Mip);
}
}
else
{
// if image is in BGRA8 format leave it, otherwise use original RGBA32F
ERawImageFormat::Type DestFormat = Image.Format == ERawImageFormat::BGRA8 ? ERawImageFormat::BGRA8 : ERawImageFormat::RGBA32F;
Image.CopyTo(*Mip, DestFormat, Image.GammaSpace);
}
}
}
if (BuildSettings.Downscale > 1.f)
{
FTextureDownscaleSettings DownscaleSettings;
DownscaleSettings.Downscale = BuildSettings.Downscale;
DownscaleSettings.DownscaleOptions = BuildSettings.DownscaleOptions;
DownscaleSettings.BlockSize = 4;
DownscaleSettings.UseNewMipFilter = BuildSettings.bUseNewMipFilter;
DownscaleImage(*Mip, *Mip, DownscaleSettings);
}
if (BuildSettings.bHasColorSpaceDefinition)
{
Mip->TransformToWorkingColorSpace(
FVector2d(BuildSettings.RedChromaticityCoordinate),
FVector2d(BuildSettings.GreenChromaticityCoordinate),
FVector2d(BuildSettings.BlueChromaticityCoordinate),
FVector2d(BuildSettings.WhiteChromaticityCoordinate),
static_cast<UE::Color::EChromaticAdaptationMethod>(BuildSettings.ChromaticAdaptationMethod));
}
// Apply color adjustments
AdjustImageColors(*Mip, BuildSettings);
if (BuildSettings.bComputeBokehAlpha)
{
// To get the occlusion in the BokehDOF shader working for all Bokeh textures.
ComputeBokehAlpha(*Mip);
}
if (BuildSettings.bFlipGreenChannel)
{
FlipGreenChannel(*Mip);
}
}
check( OutMipChain.Num() == CopyCount );
check( GenerateCount == NumOutputMips - OutMipChain.Num() );
// Generate any missing mips in the chain.
if ( GenerateCount > 0 )
{
// Do angular filtering of cubemaps if requested.
if (BuildSettings.MipGenSettings == TMGS_Angular)
{
check( BuildSettings.bCubemap );
// note TMGS_Angular forces dim to next lower power of 2
// note GenerateAngularFilteredMips reprocesses ALL the mips, not just GenerateCount
// this should probably be outside the GenerateCount check (eg. always done, even if GenerateCount == 0 )
// but putting it inside matches existing behavior
// I guess it's moot because you can't set NoMipMips or LeaveExisting if you chose Angular
GenerateAngularFilteredMips(OutMipChain, NumOutputMips, BuildSettings.DiffuseConvolveMipLevel);
}
else
{
// GenerateMipChain should bring us up to NumOutputMips
// but it doesn't take NumOutputMips as a param, makes its own decision
// we will check that it chose the same mip count after
// you could pass GenerateCount as the large arg here
// and it should make the same result
GenerateMipChain(BuildSettings, OutMipChain.Last(), OutMipChain, MAX_uint32);
}
}
check(OutMipChain.Num() == NumOutputMips);
// Apply post-mip generation adjustments.
if (BuildSettings.bReplicateRed)
{
ReplicateRedChannel(OutMipChain);
}
else if (BuildSettings.bReplicateAlpha)
{
ReplicateAlphaChannel(OutMipChain);
}
if (BuildSettings.bApplyYCoCgBlockScale)
{
ApplyYCoCgBlockScale(OutMipChain);
}
return true;
}
// @param CompositeTextureMode original type ECompositeTextureMode
// @return true on success, false on failure. Can fail due to bad mismatched dimensions of incomplete mip chains.
bool ApplyCompositeTexture(TArray<FImage>& RoughnessSourceMips, const TArray<FImage>& NormalSourceMips, uint8 CompositeTextureMode, float CompositePower)
{
uint32 MinLevel = FMath::Min(RoughnessSourceMips.Num(), NormalSourceMips.Num());
if( RoughnessSourceMips[RoughnessSourceMips.Num() - MinLevel].SizeX != NormalSourceMips[NormalSourceMips.Num() - MinLevel].SizeX ||
RoughnessSourceMips[RoughnessSourceMips.Num() - MinLevel].SizeY != NormalSourceMips[NormalSourceMips.Num() - MinLevel].SizeY )
{
UE_LOG(LogTextureCompressor, Warning, TEXT("Couldn't apply composite texture as RoughnessSourceMips (mip %d, %d x %d) doesn't match NormalSourceMips (mip %d, %d x %d); mipchain might be mismatched/incomplete"),
RoughnessSourceMips.Num() - MinLevel,
RoughnessSourceMips[RoughnessSourceMips.Num() - MinLevel].SizeX,
RoughnessSourceMips[RoughnessSourceMips.Num() - MinLevel].SizeY,
NormalSourceMips.Num() - MinLevel,
NormalSourceMips[NormalSourceMips.Num() - MinLevel].SizeX,
NormalSourceMips[NormalSourceMips.Num() - MinLevel].SizeY
);
return false;
}
for(uint32 Level = 0; Level < MinLevel; ++Level)
{
::ApplyCompositeTexture(RoughnessSourceMips[RoughnessSourceMips.Num() - 1 - Level], NormalSourceMips[NormalSourceMips.Num() - 1 - Level], CompositeTextureMode, CompositePower);
}
return true;
}
};
IMPLEMENT_MODULE(FTextureCompressorModule, TextureCompressor)
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