Yeah, I'm having some trouble decoding the 4bpp graphics file format It's acting all weird... Here's what I would expect to happen:
4 bits per each pixel, or 1 nybble is used for one pixel, so 2 bytes should control 4 pixels. That seems to be correct (I'm checking in transelhextion), the weird part comes next. When I make the first color use color 2 (0 indexed) and the rest of them use color 0, the first two bytes in the file are 00 and 87. If I make it use color 0 all across, I get 00 and 07. When I change the first pixel to color F, the bytes become 80 and 87. I can't see any discernible pattern here, it seems that different nybbles are controlling the same pixel depending on what the color is, but that makes no sense, so I guess I'm missing something?
4 bits per each pixel, or 1 nybble is used for one pixel, so 2 bytes should control 4 pixels. That seems to be correct (I'm checking in transelhextion), the weird part comes next. When I make the first color use color 2 (0 indexed) and the rest of them use color 0, the first two bytes in the file are 00 and 87. If I make it use color 0 all across, I get 00 and 07. When I change the first pixel to color F, the bytes become 80 and 87. I can't see any discernible pattern here, it seems that different nybbles are controlling the same pixel depending on what the color is, but that makes no sense, so I guess I'm missing something?