What is prusa-mmu-t-remap?

Prusa MMU T-Remap is a tool for people who use Prusa 3D printers with a Multi Material Unit (MMU2 or MMU3), the accessory that lets a printer swap between several spools of filament during a single print. Normally the order you set up filament colors in PrusaSlicer has to match the physical order the spools are loaded into the MMU cassettes, and if they do not match, the printer ends up loading the wrong color. This project rewrites the gcode file after slicing so that each color you picked in the slicer gets sent to the correct physical slot, without changing anything else in the file. The tool has a graphical interface built with Python's tkinter library. You load a gcode file, and for each color used in the print you tell the tool which physical slot it is actually loaded in. It then produces a corrected gcode file ready to send to the printer. It can also be set up as a post processing script inside PrusaSlicer, so the interface opens automatically each time you export a print. Beyond simple remapping, the tool fixes a few quirks in how the Prusa firmware handles the MMU. It can activate slots that are not actually used in a print so the firmware does not get confused, it can move the color used for the printed brim, and it will detect and warn if you try to reprocess a file that has already been remapped, since doing that twice would corrupt the color assignments. It works with plain gcode files exported from PrusaSlicer, but not yet with the newer compressed bgcode format, so users on recent PrusaSlicer versions may need to turn that option off first. The project was built by someone without a programming background, using Claude AI for the coding, in response to a feature that competing printer brands already offer. It has been tested on a Prusa MK4S with the standard 3 slot MMU3 and a modified 12 slot version, and the developer welcomes reports from people testing it on other Prusa printer models with an MMU.