Function ILAPIENTRY ilGetDXTCData

DevIL/src-IL/src/il_dds-save.cpp:312–363

ILuint ILAPIENTRY ilGetDXTCData(void *Buffer, ILuint BufferSize, ILenum DXTCFormat)
{
	ILubyte	*CurData = NULL;
	ILuint	retVal;
	ILint	BlockNum;

	if (Buffer == NULL) {  // Return the number that will be written with a subsequent call.
		BlockNum = ((iCurImage->Width + 3)/4) * ((iCurImage->Height + 3)/4)
					* iCurImage->Depth;

		switch (DXTCFormat)
		{
			case IL_DXT1:
			case IL_DXT1A:
			case IL_ATI1N:
				return BlockNum * 8;
			case IL_DXT3:
			case IL_DXT5:
			case IL_3DC:
			case IL_RXGB:
				return BlockNum * 16;
			default:
				ilSetError(IL_FORMAT_NOT_SUPPORTED);
				return 0;
		}
	}

	if (DXTCFormat == iCurImage->DxtcFormat && iCurImage->DxtcSize && iCurImage->DxtcData) {
		memcpy(Buffer, iCurImage->DxtcData, IL_MIN(BufferSize, iCurImage->DxtcSize));
		return IL_MIN(BufferSize, iCurImage->DxtcSize);
	}

	if (iCurImage->Origin != IL_ORIGIN_UPPER_LEFT) {
		CurData = iCurImage->Data;
		iCurImage->Data = iGetFlipped(iCurImage);
		if (iCurImage->Data == NULL) {
			iCurImage->Data = CurData;
			return 0;
		}
	}

	//@TODO: Is this the best way to do this?
	iSetOutputLump(Buffer, BufferSize);
	retVal = Compress(iCurImage, DXTCFormat);

	if (iCurImage->Origin != IL_ORIGIN_UPPER_LEFT) {
		ifree(iCurImage->Data);
		iCurImage->Data = CurData;
	}

	return retVal;
}


// Added the next two functions based on Charles Bloom's rant at