pxart's grid-plus-keyed-palette format is close to XPM2 without its header. It sits in the same family as the sprite formats of PuzzleScript, MakeCode Arcade and Bitsy. PixTXT (MIT) is the nearest standalone format. pxart's optional version line, built-in transparent ., located error codes, palette variants and lenient handling of unknown sections all come from it.

License

MIT