Function unpack_block

engine/dlib/src/basis/encoder/basisu_gpu_texture.cpp:1095–1207

Unpacks to RGBA, R, RG, or A

	
	// Unpacks to RGBA, R, RG, or A
	bool unpack_block(texture_format fmt, const void* pBlock, color_rgba* pPixels)
	{
		switch (fmt)
		{
		case texture_format::cBC1:
		{
			unpack_bc1(pBlock, pPixels, true);
			break;
		}
		case texture_format::cBC1_NV:
		{
			unpack_bc1_nv(pBlock, pPixels, true);
			break;
		}
		case texture_format::cBC1_AMD:
		{
			unpack_bc1_amd(pBlock, pPixels, true);
			break;
		}
		case texture_format::cBC3:
		{
			return unpack_bc3(pBlock, pPixels);
		}
		case texture_format::cBC4:
		{
			// Unpack to R
			unpack_bc4(pBlock, &pPixels[0].r, sizeof(color_rgba));
			break;
		}
		case texture_format::cBC5:
		{
			unpack_bc5(pBlock, pPixels);
			break;
		}
		case texture_format::cBC7:
		{
			return unpack_bc7(pBlock, pPixels);
		}
		// Full ETC2 color blocks (planar/T/H modes) is currently unsupported in basisu, but we do support ETC2 with alpha (using ETC1 for color)
		case texture_format::cETC2_RGB:
		case texture_format::cETC1:
		case texture_format::cETC1S:
		{
			return unpack_etc1(*static_cast<const etc_block*>(pBlock), pPixels);
		}
		case texture_format::cETC2_RGBA:
		{
			if (!unpack_etc1(static_cast<const etc_block*>(pBlock)[1], pPixels))
				return false;
			unpack_etc2_eac(pBlock, pPixels);
			break;
		}
		case texture_format::cETC2_ALPHA:
		{
			// Unpack to A
			unpack_etc2_eac(pBlock, pPixels);
			break;
		}