void Image_DXTC::Decompress()
{
VERIFY( m_pCompBytes );
AllocateDecompBytes();
VERIFY( m_pDecompBytes ); // must already have allocated memory
switch( m_CompFormat )
{
case PF_DXT1 :
//TRACE( "Decompressing image format: DXT1\n" );
DecompressDXT1();
break;
case PF_DXT2 :
//TRACE( "Decompressing image format: DXT2\n" );
DecompressDXT2();
break;
case PF_DXT3 :
//TRACE( "Decompressing image format: DXT3\n" );
DecompressDXT3();
break;
case PF_DXT4 :
//TRACE( "Decompressing image format: DXT4\n" );
DecompressDXT4();
break;
case PF_DXT5 :
//TRACE( "Decompressing image format: DXT5\n" );
DecompressDXT5();
break;
case PF_UNKNOWN :
break;
}
//. swap R<->B channels
for (int y=0; y<m_nHeight; y++)
{
for (int x=0; x<m_nWidth; x++)
{
BYTE* ptr = m_pDecompBytes + (y*m_nWidth+x)*4;
swap (ptr[0],ptr[2]);
}
}
}
// Internal function used to load the BLP.
ILboolean iLoadBlpInternal(void)
{
BLP2HEAD Header;
ILubyte *CompData;
ILimage *Image;
ILuint Mip, j, x, CompSize, AlphaSize, AlphaOff;
ILint y;
ILboolean BaseCreated = IL_FALSE;
ILubyte *DataAndAlpha = NULL, *Palette = NULL, AlphaMask; //, *JpegHeader, *JpegData;
if (iCurImage == NULL) {
ilSetError(IL_ILLEGAL_OPERATION);
return IL_FALSE;
}
if (!iGetBlp2Head(&Header)) {
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
if (!iCheckBlp2(&Header)) {
goto check_blp1;
}
//@TODO: Remove this!
if (Header.Type != BLP_TYPE_DXTC_RAW)
return IL_FALSE;
switch (Header.Compression)
{
case BLP_RAW:
for (Mip = 0; Mip < 16; Mip++) { // Possible maximum of 16 mipmaps
if (BaseCreated) {
if (Header.HasMips == 0) // Does not have mipmaps, so we are done.
break;
if (Image->Width == 1 && Image->Height == 1) // Already at the smallest mipmap (1x1), so we are done.
break;
if (Header.MipOffsets[Mip] == 0 || Header.MipLengths == 0) // No more mipmaps in the file.
break;
}
switch (Header.AlphaBits)
{
case 0:
if (!BaseCreated) { // Have not created the base image yet, so use ilTexImage.
if (!ilTexImage(Header.Width, Header.Height, 1, 1, IL_COLOUR_INDEX, IL_UNSIGNED_BYTE, NULL))
return IL_FALSE;
Image = iCurImage;
BaseCreated = IL_TRUE;
Image->Pal.Palette = (ILubyte*)ialloc(256 * 4); // 256 entries of ARGB8888 values (1024).
if (Image->Pal.Palette == NULL)
return IL_FALSE;
Image->Pal.PalSize = 1024;
Image->Pal.PalType = IL_PAL_BGRA32; //@TODO: Find out if this is really BGRA data.
if (iread(Image->Pal.Palette, 1, 1024) != 1024) // Read in the palette.
return IL_FALSE;
}
else {
Image->Mipmaps = ilNewImageFull(Image->Width >> 1, Image->Height >> 1, 1, 1, IL_COLOUR_INDEX, IL_UNSIGNED_BYTE, NULL);
if (Image->Mipmaps == NULL)
return IL_FALSE;
// Copy the palette from the first image before we change our Image pointer.
iCopyPalette(&Image->Mipmaps->Pal, &Image->Pal);
// Move to the next mipmap in the linked list.
Image = Image->Mipmaps;
}
// The origin should be in the upper left.
Image->Origin = IL_ORIGIN_UPPER_LEFT;
// These two should be the same (tells us how much data is in the file for this mipmap level).
if (Header.MipLengths[Mip] != Image->SizeOfData) {
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
// Finally read in the image data.
iseek(Header.MipOffsets[Mip], IL_SEEK_SET);
if (iread(Image->Data, 1, Image->SizeOfData) != Image->SizeOfData)
return IL_FALSE;
break;
case 1:
if (!BaseCreated) { // Have not created the base image yet, so use ilTexImage.
if (!ilTexImage(Header.Width, Header.Height, 1, 4, IL_BGRA, IL_UNSIGNED_BYTE, NULL))
return IL_FALSE;
Image = iCurImage;
BaseCreated = IL_TRUE;
Palette = (ILubyte*)ialloc(256 * 4);
if (Palette == NULL)
return IL_FALSE;
// Read in the palette.
if (iread(Palette, 1, 1024) != 1024) {
ifree(Palette);
return IL_FALSE;
}
// We only allocate this once and reuse this buffer with every mipmap (since successive ones are smaller).
DataAndAlpha = (ILubyte*)ialloc(Image->Width * Image->Height);
if (DataAndAlpha == NULL) {
ifree(DataAndAlpha);
ifree(Palette);
return IL_FALSE;
}
}
else {
Image->Mipmaps = ilNewImageFull(Image->Width >> 1, Image->Height >> 1, 1, 4, IL_BGRA, IL_UNSIGNED_BYTE, NULL);
if (Image->Mipmaps == NULL)
return IL_FALSE;
// Move to the next mipmap in the linked list.
Image = Image->Mipmaps;
}
// The origin should be in the upper left.
Image->Origin = IL_ORIGIN_UPPER_LEFT;
// Determine the size of the alpha data following the color indices.
AlphaSize = Image->Width * Image->Height / 8;
if (AlphaSize == 0)
AlphaSize = 1; // Should never be 0.
// These two should be the same (tells us how much data is in the file for this mipmap level).
if (Header.MipLengths[Mip] != Image->SizeOfData / 4 + AlphaSize) {
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
// Seek to the data and read it.
iseek(Header.MipOffsets[Mip], IL_SEEK_SET);
if (iread(DataAndAlpha, Image->Width * Image->Height, 1) != 1) {
ifree(DataAndAlpha);
ifree(Palette);
return IL_FALSE;
}
// Convert the color-indexed data to BGRX.
for (j = 0; j < Image->Width * Image->Height; j++) {
Image->Data[j*4] = Palette[DataAndAlpha[j]*4];
Image->Data[j*4+1] = Palette[DataAndAlpha[j]*4+1];
Image->Data[j*4+2] = Palette[DataAndAlpha[j]*4+2];
}
// Read in the alpha list.
if (iread(DataAndAlpha, AlphaSize, 1) != 1) {
ifree(DataAndAlpha);
ifree(Palette);
return IL_FALSE;
}
AlphaMask = 0x01; // Lowest bit
AlphaOff = 0;
// The really strange thing about this alpha data is that it is upside-down when compared to the
// regular color-indexed data, so we have to flip it.
for (y = Image->Height - 1; y >= 0; y--) {
for (x = 0; x < Image->Width; x++) {
if (AlphaMask == 0) { // Shifting it past the highest bit makes it 0, since we only have 1 byte.
AlphaOff++; // Move along the alpha buffer.
AlphaMask = 0x01; // Reset the alpha mask.
}
// This is just 1-bit alpha, so it is either on or off.
Image->Data[Image->Bps * y + x * 4 + 3] = DataAndAlpha[AlphaOff] & AlphaMask ? 0xFF : 0x00;
AlphaMask <<= 1;
}
}
break;
default:
//@TODO: Accept any other alpha values?
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
}
// Done, so we can finally free these two.
ifree(DataAndAlpha);
ifree(Palette);
break;
case BLP_DXTC:
for (Mip = 0; Mip < 16; Mip++) { // Possible maximum of 16 mipmaps
//@TODO: Other formats
//if (Header.AlphaBits == 0)
// if (!ilTexImage(Header.Width, Header.Height, 1, 3, IL_RGB, IL_UNSIGNED_BYTE, NULL))
// return IL_FALSE;
if (!BaseCreated) { // Have not created the base image yet, so use ilTexImage.
if (!ilTexImage(Header.Width, Header.Height, 1, 4, IL_RGBA, IL_UNSIGNED_BYTE, NULL))
return IL_FALSE;
Image = iCurImage;
BaseCreated = IL_TRUE;
}
else {
if (Header.HasMips == 0) // Does not have mipmaps, so we are done.
break;
if (Image->Width == 1 && Image->Height == 1) // Already at the smallest mipmap (1x1), so we are done.
break;
if (Header.MipOffsets[Mip] == 0 || Header.MipLengths[Mip] == 0) // No more mipmaps in the file.
break;
//@TODO: Other formats
// ilNewImageFull automatically changes widths and heights of 0 to 1, so we do not have to worry about it.
Image->Mipmaps = ilNewImageFull(Image->Width >> 1, Image->Height >> 1, 1, 4, IL_RGBA, IL_UNSIGNED_BYTE, NULL);
if (Image->Mipmaps == NULL)
return IL_FALSE;
Image = Image->Mipmaps;
}
// The origin should be in the upper left.
Image->Origin = IL_ORIGIN_UPPER_LEFT;
//@TODO: Only do the allocation once.
CompData = (ILubyte*)ialloc(Header.MipLengths[Mip]);
if (CompData == NULL)
return IL_FALSE;
// Read in the compressed mipmap data.
iseek(Header.MipOffsets[Mip], IL_SEEK_SET);
if (iread(CompData, 1, Header.MipLengths[Mip]) != Header.MipLengths[Mip]) {
ifree(CompData);
return IL_FALSE;
}
switch (Header.AlphaBits)
{
case 0: // DXT1 without alpha
case 1: // DXT1 with alpha
// Check to make sure that the MipLength reported is the size needed, so that
// DecompressDXT1 does not crash.
CompSize = ((Image->Width + 3) / 4) * ((Image->Height + 3) / 4) * 8;
if (CompSize != Header.MipLengths[Mip]) {
ilSetError(IL_INVALID_FILE_HEADER);
ifree(CompData);
return IL_FALSE;
}
if (!DecompressDXT1(Image, CompData)) {
ifree(CompData);
return IL_FALSE;
}
break;
case 8:
// Check to make sure that the MipLength reported is the size needed, so that
// DecompressDXT3/5 do not crash.
CompSize = ((Image->Width + 3) / 4) * ((Image->Height + 3) / 4) * 16;
if (CompSize != Header.MipLengths[Mip]) {
ifree(CompData);
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
switch (Header.AlphaType)
{
case 0: // All three of
case 1: // these refer to
case 8: // DXT3...
if (!DecompressDXT3(Image, CompData)) {
ifree(CompData);
return IL_FALSE;
}
break;
case 7: // DXT5 compression
if (!DecompressDXT5(Image, CompData)) {
ifree(CompData);
return IL_FALSE;
}
break;
//default: // Should already be checked by iCheckBlp2.
}
break;
//default: // Should already be checked by iCheckBlp2.
}
//@TODO: Save DXTC data.
ifree(CompData);
}
break;
//default:
}
return ilFixImage();
check_blp1:
iseek(-148, IL_SEEK_CUR); // Go back the size of the BLP2 header, since we tried reading it.
return iLoadBlp1();
}
// Internal function used to load the ROT.
ILboolean iLoadRotInternal(void)
{
ILubyte Form[4], FormName[4];
ILuint FormLen, Width, Height, Format, Channels, CompSize;
ILuint MipSize, MipLevel, MipWidth, MipHeight;
ILenum FormatIL;
ILimage *Image;
ILboolean BaseCreated = IL_FALSE;
ILubyte *CompData = NULL;
if (iCurImage == NULL) {
ilSetError(IL_ILLEGAL_OPERATION);
return IL_FALSE;
}
// The first entry in the file must be 'FORM', 0x20 in a big endian integer and then 'HEAD'.
iread(Form, 1, 4);
FormLen = GetBigUInt();
iread(FormName, 1, 4);
if (strncmp(Form, "FORM", 4) || FormLen != 0x14 || strncmp(FormName, "HEAD", 4)) {
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
// Next follows the width, height and format in the header.
Width = GetLittleUInt();
Height = GetLittleUInt();
Format = GetLittleUInt();
//@TODO: More formats.
switch (Format)
{
case ROT_RGBA32: // 32-bit RGBA format
Channels = 4;
FormatIL = IL_RGBA;
break;
case ROT_DXT1: // DXT1 (no alpha)
Channels = 4;
FormatIL = IL_RGBA;
break;
case ROT_DXT3: // DXT3
case ROT_DXT5: // DXT5
Channels = 4;
FormatIL = IL_RGBA;
// Allocates the maximum needed (the first width/height given in the file).
CompSize = ((Width + 3) / 4) * ((Height + 3) / 4) * 16;
CompData = ialloc(CompSize);
if (CompData == NULL)
return IL_FALSE;
break;
default:
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
if (Width == 0 || Height == 0) {
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
//@TODO: Find out what this is.
GetLittleUInt(); // Skip this for the moment. This appears to be the number of channels.
// Next comes 'FORM', a length and 'MIPS'.
iread(Form, 1, 4);
FormLen = GetBigUInt();
iread(FormName, 1, 4);
//@TODO: Not sure if the FormLen has to be anything specific here.
if (strncmp(Form, "FORM", 4) || strncmp(FormName, "MIPS", 4)) {
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
//@TODO: Can these mipmap levels be in any order? Some things may be easier if the answer is no.
Image = iCurImage;
do {
// Then we have 'FORM' again.
iread(Form, 1, 4);
// This is the size of the mipmap data.
MipSize = GetBigUInt();
iread(FormName, 1, 4);
if (strncmp(Form, "FORM", 4)) {
if (!BaseCreated) { // Our file is malformed.
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
// We have reached the end of the mipmap data.
break;
}
if (strncmp(FormName, "MLVL", 4)) {
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
// Next is the mipmap attributes (level number, width, height and length)
MipLevel = GetLittleUInt();
MipWidth = GetLittleUInt();
MipHeight = GetLittleUInt();
MipSize = GetLittleUInt(); // This is the same as the previous size listed -20 (for attributes).
// Lower level mipmaps cannot be larger than the main image.
if (MipWidth > Width || MipHeight > Height || MipSize > CompSize) {
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
// Just create our images here.
if (!BaseCreated) {
if (!ilTexImage(MipWidth, MipHeight, 1, Channels, FormatIL, IL_UNSIGNED_BYTE, NULL))
return IL_FALSE;
BaseCreated = IL_TRUE;
}
else {
Image->Mipmaps = ilNewImageFull(MipWidth, MipHeight, 1, Channels, FormatIL, IL_UNSIGNED_BYTE, NULL);
Image = Image->Mipmaps;
}
switch (Format)
{
case ROT_RGBA32: // 32-bit RGBA format
if (iread(Image->Data, Image->SizeOfData, 1) != 1)
return IL_FALSE;
break;
case ROT_DXT1:
// Allocates the size of the compressed data.
CompSize = ((MipWidth + 3) / 4) * ((MipHeight + 3) / 4) * 8;
if (CompSize != MipSize) {
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
CompData = ialloc(CompSize);
if (CompData == NULL)
return IL_FALSE;
// Read in the DXT1 data...
if (iread(CompData, CompSize, 1) != 1)
return IL_FALSE;
// ...and decompress it.
if (!DecompressDXT1(Image, CompData)) {
ifree(CompData);
return IL_FALSE;
}
if (ilGetInteger(IL_KEEP_DXTC_DATA) == IL_TRUE) {
Image->DxtcSize = CompSize;
Image->DxtcData = CompData;
Image->DxtcFormat = IL_DXT1;
CompData = NULL;
}
break;
case ROT_DXT3:
// Allocates the size of the compressed data.
CompSize = ((MipWidth + 3) / 4) * ((MipHeight + 3) / 4) * 16;
if (CompSize != MipSize) {
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
CompData = ialloc(CompSize);
if (CompData == NULL)
return IL_FALSE;
// Read in the DXT3 data...
if (iread(CompData, MipSize, 1) != 1)
return IL_FALSE;
// ...and decompress it.
if (!DecompressDXT3(Image, CompData)) {
ifree(CompData);
return IL_FALSE;
}
if (ilGetInteger(IL_KEEP_DXTC_DATA) == IL_TRUE) {
Image->DxtcSize = CompSize;
Image->DxtcData = CompData;
Image->DxtcFormat = IL_DXT3;
CompData = NULL;
}
break;
case ROT_DXT5:
// Allocates the size of the compressed data.
CompSize = ((MipWidth + 3) / 4) * ((MipHeight + 3) / 4) * 16;
if (CompSize != MipSize) {
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
CompData = ialloc(CompSize);
if (CompData == NULL)
return IL_FALSE;
// Read in the DXT5 data...
if (iread(CompData, MipSize, 1) != 1)
return IL_FALSE;
// ...and decompress it.
if (!DecompressDXT5(Image, CompData)) {
ifree(CompData);
return IL_FALSE;
}
// Keeps a copy
if (ilGetInteger(IL_KEEP_DXTC_DATA) == IL_TRUE) {
Image->DxtcSize = CompSize;
Image->DxtcData = CompData;
Image->DxtcFormat = IL_DXT5;
CompData = NULL;
}
break;
}
ifree(CompData); // Free it if it was not saved.
} while (!ieof()); //@TODO: Is there any other condition that should end this?
return ilFixImage();
}
