// Internal function used to load the Gif.
ILboolean iLoadGifInternal()
{
GIFHEAD Header;
ILpal GlobalPal;
if (iCurImage == NULL) {
ilSetError(IL_ILLEGAL_OPERATION);
return IL_FALSE;
}
GlobalPal.Palette = NULL;
GlobalPal.PalSize = 0;
//read header
iread(&Header.Sig, 1, 6);
Header.Width = GetLittleUShort();
Header.Height = GetLittleUShort();
Header.ColourInfo = igetc();
Header.Background = igetc();
Header.Aspect = igetc();
if (!strnicmp(Header.Sig, "GIF87A", 6)) {
GifType = GIF87A;
}
else if (!strnicmp(Header.Sig, "GIF89A", 6)) {
GifType = GIF89A;
}
else {
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
if (!ilTexImage(Header.Width, Header.Height, 1, 1, IL_COLOUR_INDEX, IL_UNSIGNED_BYTE, NULL))
return IL_FALSE;
iCurImage->Origin = IL_ORIGIN_UPPER_LEFT;
// Check for a global colour map.
if (Header.ColourInfo & (1 << 7)) {
if (!iGetPalette(Header.ColourInfo, &GlobalPal)) {
return IL_FALSE;
}
}
if (!GetImages(&GlobalPal, &Header))
return IL_FALSE;
if (GlobalPal.Palette && GlobalPal.PalSize)
ifree(GlobalPal.Palette);
GlobalPal.Palette = NULL;
GlobalPal.PalSize = 0;
ilFixImage();
return IL_TRUE;
}
// Internal function used to load the Gif.
ILboolean iLoadGifInternal(ILimage* image)
{
GIFHEAD Header;
ILpal GlobalPal;
if (image == NULL) {
ilSetError(IL_ILLEGAL_OPERATION);
return IL_FALSE;
}
GlobalPal.Palette = NULL;
GlobalPal.PalSize = 0;
// Read header
iCurImage->io.read(iCurImage->io.handle, &Header, 1, sizeof(Header));
#ifdef __BIG_ENDIAN__
iSwapUShort(Header.Width);
iSwapUShort(Header.Height);
#endif
if (strnicmp(Header.Sig, "GIF87A", 6) != 0
&& strnicmp(Header.Sig, "GIF89A", 6) != 0)
{
ilSetError(IL_INVALID_FILE_HEADER);
return IL_FALSE;
}
if (!ilTexImage(Header.Width, Header.Height, 1, 1, IL_COLOUR_INDEX, IL_UNSIGNED_BYTE, NULL))
//if (!ilTexImage(Header.Width, Header.Height, 1, 1, IL_RGB, IL_UNSIGNED_BYTE, NULL))
return IL_FALSE;
image->Origin = IL_ORIGIN_UPPER_LEFT;
// Check for a global colour map.
if (Header.ColourInfo & (1 << 7)) {
if (!iGetPalette(Header.ColourInfo, &GlobalPal, NULL)) {
return IL_FALSE;
}
}
if (!GetImages(image, &GlobalPal, &Header))
return IL_FALSE;
if (GlobalPal.Palette && GlobalPal.PalSize)
ifree(GlobalPal.Palette);
GlobalPal.Palette = NULL;
GlobalPal.PalSize = 0;
return ilFixImage();
}
ILboolean GetImages(ILpal *GlobalPal, GIFHEAD *GifHead)
{
IMAGEDESC ImageDesc, OldImageDesc;
GFXCONTROL Gfx;
ILboolean BaseImage = IL_TRUE;
ILimage *Image = iCurImage, *TempImage = NULL;
ILuint NumImages = 0, i;
ILint input;
Gfx.Used = IL_TRUE;
while (!ieof()) {
ILubyte DisposalMethod = 1;
i = itell();
if (!SkipExtensions(&Gfx))
goto error_clean;
i = itell();
if (!Gfx.Used)
DisposalMethod = (Gfx.Packed & 0x1C) >> 2;
//read image descriptor
ImageDesc.Separator = igetc();
if (ImageDesc.Separator != 0x2C) //end of image
break;
ImageDesc.OffX = GetLittleUShort();
ImageDesc.OffY = GetLittleUShort();
ImageDesc.Width = GetLittleUShort();
ImageDesc.Height = GetLittleUShort();
ImageDesc.ImageInfo = igetc();
if (ieof()) {
ilGetError(); // Gets rid of the IL_FILE_READ_ERROR that inevitably results.
break;
}
if (!BaseImage) {
NumImages++;
Image->Next = ilNewImage(iCurImage->Width, iCurImage->Height, 1, 1, 1);
if (Image->Next == NULL)
goto error_clean;
//20040612: DisposalMethod controls how the new images data is to be combined
//with the old image. 0 means that it doesn't matter how they are combined,
//1 means keep the old image, 2 means set to background color, 3 is
//load the image that was in place before the current (this is not implemented
//here! (TODO?))
if (DisposalMethod == 2 || DisposalMethod == 3)
//Note that this is actually wrong, too: If the image has a local
//color table, we should really search for the best fit of the
//background color table and use that index (?). Furthermore,
//we should only memset the part of the image that is not read
//later (if we are sure that no parts of the read image are transparent).
if (!Gfx.Used && Gfx.Packed & 0x1)
memset(Image->Next->Data, Gfx.Transparent, Image->SizeOfData);
else
memset(Image->Next->Data, GifHead->Background, Image->SizeOfData);
else if (DisposalMethod == 1 || DisposalMethod == 0)
memcpy(Image->Next->Data, Image->Data, Image->SizeOfData);
//Interlacing has to be removed after the image was copied (line above)
if (OldImageDesc.ImageInfo & (1 << 6)) { // Image is interlaced.
if (!RemoveInterlace(Image))
goto error_clean;
}
Image = Image->Next;
Image->Format = IL_COLOUR_INDEX;
Image->Origin = IL_ORIGIN_UPPER_LEFT;
}
else {
BaseImage = IL_FALSE;
if (!Gfx.Used && Gfx.Packed & 0x1)
memset(Image->Data, Gfx.Transparent, Image->SizeOfData);
else
memset(Image->Data, GifHead->Background, Image->SizeOfData);
//memset(Image->Data, GifHead->Background, Image->SizeOfData);
}
Image->OffX = ImageDesc.OffX;
Image->OffY = ImageDesc.OffY;
// Check to see if the image has its own palette.
if (ImageDesc.ImageInfo & (1 << 7)) {
if (!iGetPalette(ImageDesc.ImageInfo, &Image->Pal)) {
goto error_clean;
}
}
else {
if (!iCopyPalette(&Image->Pal, GlobalPal)) {
goto error_clean;
}
}
if (!GifGetData(Image->Data + ImageDesc.OffX + ImageDesc.OffY*Image->Width, Image->SizeOfData,
ImageDesc.Width, ImageDesc.Height, Image->Width, &Gfx)) {
ilSetError(IL_ILLEGAL_FILE_VALUE);
goto error_clean;
}
// See if there was a valid graphics control extension.
if (!Gfx.Used) {
Gfx.Used = IL_TRUE;
Image->Duration = Gfx.Delay * 10; // We want it in milliseconds.
// See if a transparent colour is defined.
if (Gfx.Packed & 1) {
if (!ConvertTransparent(Image, Gfx.Transparent)) {
goto error_clean;
}
}
}
i = itell();
// Terminates each block.
if((input = igetc()) == IL_EOF)
goto error_clean;
if (input != 0x00)
iseek(-1, IL_SEEK_CUR);
// break;
OldImageDesc = ImageDesc;
}
//Deinterlace last image
if (OldImageDesc.ImageInfo & (1 << 6)) { // Image is interlaced.
if (!RemoveInterlace(Image))
goto error_clean;
}
iCurImage->NumNext = NumImages;
if (BaseImage) // Was not able to load any images in...
return IL_FALSE;
return IL_TRUE;
error_clean:
Image = iCurImage->Next;
while (Image) {
TempImage = Image;
Image = Image->Next;
ilCloseImage(TempImage);
}
return IL_FALSE;
}
