Function DecompressBc2

trinityal/BcDecompress.cpp:112–158

}

void DecompressBc2( uint32_t width, uint32_t height, uint32_t depth, const Tr2SubresourceData& src, uint8_t* decompressed )
{
	uint32_t pitch = width * 4;
	uint32_t slice = pitch * height;
	for( uint32_t k = 0; k < depth; ++k )
	{
		const uint8_t* source = static_cast<const uint8_t*>( src.m_sysMem ) + src.m_sysMemSlicePitch * k;
		for( uint32_t j = 0; j < height; j += 4 )
		{
			for( uint32_t i = 0; i < width; i += 4 )
			{
				uint32_t color0 = ConvertBGR565A8ToBGRA8( *reinterpret_cast<const uint16_t*>( source + 8 ), 0 );
				uint32_t color1 = ConvertBGR565A8ToBGRA8( *reinterpret_cast<const uint16_t*>( source + 8 + 2 ), 0 );
				uint32_t color2 = InterpolatedColor( color0, 2, color1, 1, 1, 3 );
				uint32_t color3 = InterpolatedColor( color0, 1, color1, 2, 1, 3 );
				uint32_t bits = *reinterpret_cast<const uint32_t*>( source + 8 + 4 );
				for( uint32_t y = 0; y < 4; ++y )
				{
					for( uint32_t x = 0; x < 4; ++x )
					{
						uint32_t destY = j + y;
						uint32_t* destPixel = reinterpret_cast<uint32_t*>( decompressed + k * slice + destY * pitch + ( x + i ) * sizeof( uint32_t ) );
						unsigned alphaValue = ( *( reinterpret_cast<const uint16_t*>( source ) + y ) >> x * 4 ) & 15;
						alphaValue = alphaValue * 255 / 15;
						alphaValue <<= 24;
						switch( ( bits >> 2 * ( 4 * y + x ) ) & 3 )
						{
						case 0:
							*destPixel = color0 | alphaValue;
							break;
						case 1:
							*destPixel = color1 | alphaValue;
							break;
						case 2:
							*destPixel = color2 | alphaValue;
							break;
						case 3:
							*destPixel = color3 | alphaValue;
							break;
						}
					}
				}
				source += 16;
			}
		}
	}
}

void DecompressBc3( uint32_t width, uint32_t height, uint32_t depth, const Tr2SubresourceData& src, uint8_t* decompressed )
{