Function AdjustVolumeTexture

DevIL/src-IL/src/il_dds.cpp:570–626

The few volume textures that I have don't have consistent LinearSize entries, even though the DDS_LINEARSIZE flag is set.

// The few volume textures that I have don't have consistent LinearSize
//	entries, even though the DDS_LINEARSIZE flag is set.
void AdjustVolumeTexture(DDSHEAD *Head, ILuint CompFormat)
{
	if (Head->Depth <= 1)
		return;

	// All volume textures I've seem so far didn't have the DDS_COMPLEX flag set,
	// even though this is normally required. But because noone does set it,
	// also read images without it (TODO: check file size for 3d texture?)
	if (/*!(Head->ddsCaps1 & DDS_COMPLEX) ||*/ !(Head->ddsCaps2 & DDS_VOLUME)) {
		Head->Depth = 1;
		Depth = 1;
	}

	switch (CompFormat)
	{
		case PF_ARGB:
		case PF_RGB:
		case PF_LUMINANCE:
		case PF_LUMINANCE_ALPHA:
			//don't use the iCompFormatToBpp() function because this way
			//argb images with only 8 bits (eg. a1r2g3b2) work as well
			Head->LinearSize = IL_MAX(1,Head->Width) * IL_MAX(1,Head->Height) *
				(Head->RGBBitCount / 8);
			break;
	
		case PF_DXT1:

		case PF_ATI1N:
			Head->LinearSize = ((Head->Width+3)/4) * ((Head->Height+3)/4) * 8;
			break;

		case PF_DXT2:
		case PF_DXT3:
		case PF_DXT4:
		case PF_DXT5:
		case PF_3DC:
		case PF_RXGB:
			Head->LinearSize = ((Head->Width+3)/4) * ((Head->Height+3)/4) * 16;
			break;

		case PF_A16B16G16R16:
		case PF_R16F:
		case PF_G16R16F:
		case PF_A16B16G16R16F:
		case PF_R32F:
		case PF_G32R32F:
		case PF_A32B32G32R32F:
			Head->LinearSize = IL_MAX(1,Head->Width) * IL_MAX(1,Head->Height) *
				iCompFormatToBpp(CompFormat);
			break;
	}

	Head->Flags1 |= DDS_LINEARSIZE;
	Head->LinearSize *= Head->Depth;

	return;
}