Function decodeBlockBc7

3rdparty/bimg/src/image.cpp:2359–2549

	};

	static void decodeBlockBc7(uint8_t _dst[16*4], const uint8_t _src[16])
	{
		if (!BX_ENABLED(BIMG_DECODE_BC7) )
		{
			return;
		}

		BitReader bit(_src);

		uint8_t mode = 0;
		for (; mode < 8 && 0 == bit.read(1); ++mode)
		{
		}

		if (mode == 8)
		{
			bx::memSet(_dst, 0, 16*4);
			return;
		}

		const Bc7ModeInfo& mi  = s_bp7ModeInfo[mode];
		const uint8_t modePBits = 0 != mi.endpointPBits
			? mi.endpointPBits
			: mi.sharedPBits
			;

		const uint8_t partitionSetIdx    = uint8_t(bit.read(mi.partitionBits) );
		const uint8_t rotationMode       = uint8_t(bit.read(mi.rotationBits) );
		const uint8_t indexSelectionMode = uint8_t(bit.read(mi.indexSelectionBits) );

		uint8_t epR[6];
		uint8_t epG[6];
		uint8_t epB[6];
		uint8_t epA[6];

		for (uint8_t ii = 0; ii < mi.numSubsets; ++ii)
		{
			epR[ii*2+0] = uint8_t(bit.read(mi.colorBits) << modePBits);
			epR[ii*2+1] = uint8_t(bit.read(mi.colorBits) << modePBits);
		}

		for (uint8_t ii = 0; ii < mi.numSubsets; ++ii)
		{
			epG[ii*2+0] = uint8_t(bit.read(mi.colorBits) << modePBits);
			epG[ii*2+1] = uint8_t(bit.read(mi.colorBits) << modePBits);
		}

		for (uint8_t ii = 0; ii < mi.numSubsets; ++ii)
		{
			epB[ii*2+0] = uint8_t(bit.read(mi.colorBits) << modePBits);
			epB[ii*2+1] = uint8_t(bit.read(mi.colorBits) << modePBits);
		}

		if (mi.alphaBits)
		{
			for (uint8_t ii = 0; ii < mi.numSubsets; ++ii)
			{
				epA[ii*2+0] = uint8_t(bit.read(mi.alphaBits) << modePBits);