Function LoadUncompressedBMP

common/Image.cpp:822–1005

}

bool LoadUncompressedBMP(u32* pixels, const u8* src, const u8* data, u32 width, u32 height, const BMPInfoHeader& info_header, const std::vector<u32>& palette, bool flip_vertical, u32 red_mask = 0, u32 green_mask = 0, u32 blue_mask = 0, u32 alpha_mask = 0, bool use_alpha = false)
{
	const u32 row_size = ((width * info_header.bit_count + 31) / 32) * 4;

	for (u32 y = 0; y < height; y++)
	{
		u32 dst_y = flip_vertical ? (height - 1 - y) : y;
		const u8* row_src = src + (y * row_size);
		u32* row_dst = pixels + (dst_y * width);

		u32 bit_offset = 0;

		for (u32 x = 0; x < width; x++)
		{
			u32 pixel_value = 0;

			switch (info_header.bit_count)
			{
				case 1:
				{
					const u32 byte_index = bit_offset / 8;
					const u32 bit_index = 7 - (bit_offset % 8);
					pixel_value = (row_src[byte_index] >> bit_index) & 1;
					bit_offset += 1;
					break;
				}
				case 4:
				{
					const u32 byte_index = bit_offset / 8;
					const u32 nibble_index = (bit_offset % 8) / 4;
					pixel_value = (row_src[byte_index] >> (nibble_index * 4)) & 0xF;
					bit_offset += 4;
					break;
				}
				case 8:
				{
					pixel_value = row_src[bit_offset / 8];
					bit_offset += 8;
					break;
				}
				case 16:
				{
					const u32 byte_index = bit_offset / 8;
					pixel_value = row_src[byte_index] | (row_src[byte_index + 1] << 8);
					bit_offset += 16;

					if (info_header.compression == 3)
					{
						const u8* bitfields = data + sizeof(BMPFileHeader) + info_header.size;
						const u32 r_mask = *reinterpret_cast<const u32*>(bitfields);
						const u32 g_mask = *reinterpret_cast<const u32*>(bitfields + 4);
						const u32 b_mask = *reinterpret_cast<const u32*>(bitfields + 8);

						u32 r_shift = 0, g_shift = 0, b_shift = 0;
						u32 temp = r_mask;
						while (temp >>= 1)
							r_shift++;
						temp = g_mask;