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UnrealEngineUWP/Engine/Source/Runtime/ImageWrapper/Private/Formats/BmpImageWrapper.cpp
Andrew Davidson 10bca5261b Double math ambiguity Engine fixes
#rb jeanfrancois.dube, trivial

[CL 14974758 by Andrew Davidson in ue5-main branch]
2021-01-04 07:59:22 -04:00

317 lines
10 KiB
C++

// Copyright Epic Games, Inc. All Rights Reserved.
#include "BmpImageWrapper.h"
#include "ImageWrapperPrivate.h"
#include "BmpImageSupport.h"
/**
* BMP image wrapper class.
* This code was adapted from UTextureFactory::ImportTexture, but has not been throughly tested.
*/
FBmpImageWrapper::FBmpImageWrapper(bool bInHasHeader, bool bInHalfHeight)
: FImageWrapperBase()
, bHasHeader(bInHasHeader)
, bHalfHeight(bInHalfHeight)
{
}
void FBmpImageWrapper::Compress(int32 Quality)
{
checkf(false, TEXT("BMP compression not supported"));
}
void FBmpImageWrapper::Uncompress(const ERGBFormat InFormat, const int32 InBitDepth)
{
const uint8* Buffer = CompressedData.GetData();
if (!bHasHeader || ((CompressedData.Num()>=sizeof(FBitmapFileHeader)+sizeof(FBitmapInfoHeader)) && Buffer[0]=='B' && Buffer[1]=='M'))
{
UncompressBMPData(InFormat, InBitDepth);
}
}
void FBmpImageWrapper::UncompressBMPData(const ERGBFormat InFormat, const int32 InBitDepth)
{
const uint8* Buffer = CompressedData.GetData();
const FBitmapInfoHeader* bmhdr = nullptr;
const uint8* Bits = nullptr;
EBitmapHeaderVersion HeaderVersion = EBitmapHeaderVersion::BHV_BITMAPINFOHEADER;
if (bHasHeader)
{
bmhdr = (FBitmapInfoHeader *)(Buffer + sizeof(FBitmapFileHeader));
Bits = Buffer + ((FBitmapFileHeader *)Buffer)->bfOffBits;
HeaderVersion = ((FBitmapFileHeader *)Buffer)->GetHeaderVersion();
}
else
{
bmhdr = (FBitmapInfoHeader *)Buffer;
Bits = Buffer + sizeof(FBitmapInfoHeader);
}
if (bmhdr->biCompression != BCBI_RGB && bmhdr->biCompression != BCBI_BITFIELDS)
{
UE_LOG(LogImageWrapper, Error, TEXT("RLE compression of BMP images not supported"));
return;
}
if (bmhdr->biPlanes==1 && bmhdr->biBitCount==8)
{
// Do palette.
const uint8* bmpal = (uint8*)CompressedData.GetData() + sizeof(FBitmapFileHeader) + sizeof(FBitmapInfoHeader);
// Set texture properties.
Width = bmhdr->biWidth;
const bool bNegativeHeight = (bmhdr->biHeight < 0);
Height = FMath::Abs(bHalfHeight ? bmhdr->biHeight / 2 : bmhdr->biHeight);
Format = ERGBFormat::BGRA;
RawData.Empty(Height * Width * 4);
RawData.AddUninitialized(Height * Width * 4);
FColor* ImageData = (FColor*)RawData.GetData();
// If the number for color palette entries is 0, we need to default to 2^biBitCount entries. In this case 2^8 = 256
int32 clrPaletteCount = bmhdr->biClrUsed ? bmhdr->biClrUsed : 256;
TArray<FColor> Palette;
for (int32 i = 0; i < clrPaletteCount; i++)
{
Palette.Add(FColor(bmpal[i * 4 + 2], bmpal[i * 4 + 1], bmpal[i * 4 + 0], 255));
}
while (Palette.Num() < 256)
{
Palette.Add(FColor(0, 0, 0, 255));
}
// Copy scanlines, accounting for scanline direction according to the Height field.
const int32 SrcStride = Align(Width, 4);
const int32 SrcPtrDiff = bNegativeHeight ? SrcStride : -SrcStride;
const uint8* SrcPtr = Bits + (bNegativeHeight ? 0 : Height - 1) * SrcStride;
for (int32 Y = 0; Y < Height; Y++)
{
for (int32 X = 0; X < Width; X++)
{
*ImageData++ = Palette[SrcPtr[X]];
}
SrcPtr += SrcPtrDiff;
}
}
else if (bmhdr->biPlanes==1 && bmhdr->biBitCount==24)
{
// Set texture properties.
Width = bmhdr->biWidth;
const bool bNegativeHeight = (bmhdr->biHeight < 0);
Height = FMath::Abs(bHalfHeight ? bmhdr->biHeight / 2 : bmhdr->biHeight);
Format = ERGBFormat::BGRA;
RawData.Empty(Height * Width * 4);
RawData.AddUninitialized(Height * Width * 4);
uint8* ImageData = RawData.GetData();
// Copy scanlines, accounting for scanline direction according to the Height field.
const int32 SrcStride = Align(Width * 3, 4);
const int32 SrcPtrDiff = bNegativeHeight ? SrcStride : -SrcStride;
const uint8* SrcPtr = Bits + (bNegativeHeight ? 0 : Height - 1) * SrcStride;
for (int32 Y = 0; Y < Height; Y++)
{
const uint8* SrcRowPtr = SrcPtr;
for (int32 X = 0; X < Width; X++)
{
*ImageData++ = *SrcRowPtr++;
*ImageData++ = *SrcRowPtr++;
*ImageData++ = *SrcRowPtr++;
*ImageData++ = 0xFF;
}
SrcPtr += SrcPtrDiff;
}
}
else if (bmhdr->biPlanes==1 && bmhdr->biBitCount==32)
{
// Set texture properties.
Width = bmhdr->biWidth;
const bool bNegativeHeight = (bmhdr->biHeight < 0);
Height = FMath::Abs(bHalfHeight ? bmhdr->biHeight / 2 : bmhdr->biHeight);
Format = ERGBFormat::BGRA;
RawData.Empty(Height * Width * 4);
RawData.AddUninitialized(Height * Width * 4);
uint8* ImageData = RawData.GetData();
// Copy scanlines, accounting for scanline direction according to the Height field.
const int32 SrcStride = Width * 4;
const int32 SrcPtrDiff = bNegativeHeight ? SrcStride : -SrcStride;
const uint8* SrcPtr = Bits + (bNegativeHeight ? 0 : Height - 1) * SrcStride;
// Getting the bmiColors member from the BITMAPINFO, which is used as a mask on BitFields compression.
const FBmiColorsMask* ColorMask = (FBmiColorsMask*)(CompressedData.GetData() + sizeof(FBitmapFileHeader) + sizeof(FBitmapInfoHeader));
// Header version 4 introduced the option to declare custom color space, so we can't just assume sRGB past that version.
const bool bAssumeRGBCompression = bmhdr->biCompression == BCBI_RGB
|| (bmhdr->biCompression == BCBI_BITFIELDS && ColorMask->IsMaskRGB8() && HeaderVersion < EBitmapHeaderVersion::BHV_BITMAPV4HEADER);
if (bAssumeRGBCompression)
{
for (int32 Y = 0; Y < Height; Y++)
{
const uint8* SrcRowPtr = SrcPtr;
for (int32 X = 0; X < Width; X++)
{
*ImageData++ = *SrcRowPtr++;
*ImageData++ = *SrcRowPtr++;
*ImageData++ = *SrcRowPtr++;
*ImageData++ = 0xFF; //In BCBI_RGB compression the last 8 bits of the pixel are not used.
SrcRowPtr++;
}
SrcPtr += SrcPtrDiff;
}
}
else if (bmhdr->biCompression == BCBI_BITFIELDS)
{
//If the header version is V4 or higher we need to make sure we are still using sRGB format
if (HeaderVersion >= EBitmapHeaderVersion::BHV_BITMAPV4HEADER)
{
const FBitmapInfoHeaderV4* bmhdrV4 = (FBitmapInfoHeaderV4*)(Buffer + sizeof(FBitmapFileHeader));
if (bmhdrV4->biCSType != (uint32)EBitmapCSType::BCST_LCS_sRGB && bmhdrV4->biCSType != (uint32)EBitmapCSType::BCST_LCS_WINDOWS_COLOR_SPACE)
{
UE_LOG(LogImageWrapper, Error, TEXT("BMP uses an unsupported custom color space definition, sRGB color space will be used instead."));
}
}
//Calculating the bit mask info needed to remap the pixels' color values.
uint32 TrailingBits[4];
float MappingRatio[4];
for (uint32 MaskIndex = 0; MaskIndex < 4; MaskIndex++)
{
TrailingBits[MaskIndex] = FMath::CountTrailingZeros(ColorMask->RGBAMask[MaskIndex]);
const uint32 NumberOfBits = 32 - (TrailingBits[MaskIndex] + FMath::CountLeadingZeros(ColorMask->RGBAMask[MaskIndex]));
MappingRatio[MaskIndex] = NumberOfBits == 0 ? 0 : (FMath::Exp2(8.f) - 1) / (FMath::Exp2(static_cast<float>(NumberOfBits)) - 1);
}
//In header pre-version 4, we should ignore the last 32bit (alpha) content.
const bool bHasAlphaChannel = ColorMask->RGBAMask[3] != 0 && HeaderVersion >= EBitmapHeaderVersion::BHV_BITMAPV4HEADER;
for (int32 Y = 0; Y < Height; Y++)
{
const uint32* SrcPixel = (uint32*)SrcPtr;
for (int32 X = 0; X < Width; X++)
{
// Set the color values in BGRA order.
for (int32 ColorIndex = 2; ColorIndex >= 0; ColorIndex--)
{
*ImageData++ = FMath::RoundToInt(((*SrcPixel & ColorMask->RGBAMask[ColorIndex]) >> TrailingBits[ColorIndex]) * MappingRatio[ColorIndex]);
}
*ImageData++ = bHasAlphaChannel ? FMath::RoundToInt(((*SrcPixel & ColorMask->RGBAMask[3]) >> TrailingBits[3]) * MappingRatio[3]) : 0xFF;
SrcPixel++;
}
SrcPtr += SrcPtrDiff;
}
}
else
{
UE_LOG(LogImageWrapper, Error, TEXT("BMP uses an unsupported compression format (%i)"), bmhdr->biCompression)
}
}
else if (bmhdr->biPlanes==1 && bmhdr->biBitCount==16)
{
UE_LOG(LogImageWrapper, Error, TEXT("BMP 16 bit format no longer supported. Use terrain tools for importing/exporting heightmaps."));
}
else
{
UE_LOG(LogImageWrapper, Error, TEXT("BMP uses an unsupported format (%i/%i)"), bmhdr->biPlanes, bmhdr->biBitCount);
}
}
bool FBmpImageWrapper::SetCompressed(const void* InCompressedData, int64 InCompressedSize)
{
bool bResult = FImageWrapperBase::SetCompressed(InCompressedData, InCompressedSize);
return bResult && (bHasHeader ? LoadBMPHeader() : LoadBMPInfoHeader()); // Fetch the variables from the header info
}
bool FBmpImageWrapper::LoadBMPHeader()
{
const FBitmapInfoHeader* bmhdr = (FBitmapInfoHeader *)(CompressedData.GetData() + sizeof(FBitmapFileHeader));
const FBitmapFileHeader* bmf = (FBitmapFileHeader *)(CompressedData.GetData() + 0);
if ((CompressedData.Num() >= sizeof(FBitmapFileHeader) + sizeof(FBitmapInfoHeader)) && CompressedData.GetData()[0] == 'B' && CompressedData.GetData()[1] == 'M')
{
if (bmhdr->biCompression != BCBI_RGB && bmhdr->biCompression != BCBI_BITFIELDS)
{
UE_LOG(LogImageWrapper, Error, TEXT("RLE compression of BMP images not supported"));
return false;
}
if (bmhdr->biPlanes==1 && (bmhdr->biBitCount==8 || bmhdr->biBitCount==24 || bmhdr->biBitCount==32))
{
// Set texture properties.
Width = bmhdr->biWidth;
Height = FMath::Abs(bmhdr->biHeight);
Format = ERGBFormat::BGRA;
BitDepth = bmhdr->biBitCount;
return true;
}
if (bmhdr->biPlanes == 1 && bmhdr->biBitCount == 16)
{
UE_LOG(LogImageWrapper, Error, TEXT("BMP 16 bit format no longer supported. Use terrain tools for importing/exporting heightmaps."));
}
else
{
UE_LOG(LogImageWrapper, Error, TEXT("BMP uses an unsupported format (%i/%i)"), bmhdr->biPlanes, bmhdr->biBitCount);
}
}
return false;
}
bool FBmpImageWrapper::LoadBMPInfoHeader()
{
const FBitmapInfoHeader* bmhdr = (FBitmapInfoHeader *)CompressedData.GetData();
if (bmhdr->biCompression != BCBI_RGB && bmhdr->biCompression != BCBI_BITFIELDS)
{
UE_LOG(LogImageWrapper, Error, TEXT("RLE compression of BMP images not supported"));
return false;
}
if (bmhdr->biPlanes==1 && (bmhdr->biBitCount==8 || bmhdr->biBitCount==24 || bmhdr->biBitCount==32))
{
// Set texture properties.
Width = bmhdr->biWidth;
Height = FMath::Abs(bmhdr->biHeight);
Format = ERGBFormat::BGRA;
BitDepth = bmhdr->biBitCount;
return true;
}
if (bmhdr->biPlanes == 1 && bmhdr->biBitCount == 16)
{
UE_LOG(LogImageWrapper, Error, TEXT("BMP 16 bit format no longer supported. Use terrain tools for importing/exporting heightmaps."));
}
else
{
UE_LOG(LogImageWrapper, Error, TEXT("BMP uses an unsupported format (%i/%i)"), bmhdr->biPlanes, bmhdr->biBitCount);
}
return false;
}