VMU Screen Icon Format

On the surface, the VMU's LCD screen can only display a 1BPP 48 wide by 32 high texture. The texture is in an odd format that resembles little-endian a bit, imagine scanline order where there are 6 bytes per line except the order of those 6 bytes is reversed. Also note when the VMU is inserted into your controller it is upside down so if you want to render it "The right way up" you need to invert the horizontal axis or read from the back of the buffer to the front. For displaying on a VMU in hand-held mode this isn't a concern and can be loaded normally.

If you want to dig a bit deeper, the VMU screen is capable of displaying a range of greyscale colours thanks to the hardware quirk of the VMU screens. When a pixel turns off it doesn't go from full on to full off in an instant, instead it kind of fades out over a short-ish period of time. Using this quirk its possible to rapidly display a repeating series of 1bpp frames to give the illusion of a greyscale image. I don't know how many "BPP" of greyscale can realistically be achieved, but I do want to look at it some day. Falco Girgis' ElysianVMU emulates this hardware quirk.