u89djt
commented
2 weeks ago (Intrigued fellow user) Have you got an example model and painting to start building motivation? Being ready for complicating factors will be a thing. You'll need as many regions available per layer per colour that are each long enough to drain the change. Paint the wipe regions with the same colour as the intended region so you can give an impression of the practicality. If you want an "any colour" painting function, the slicer would have to divide those extrusions up into drain lines for each colour. Having explicit feasible examples will help motivation.
When using the MMU with Prusa Slicer I would like to paint surfaces (perimeters) as being acceptable for wiping excess material, beyond just wiping to infill or supports.
My suggestion is to add an extra color to the existing paint palette, perhaps labelled "Any Color", which indicates to the slicer that any material may be wiped onto those perimeters.
The purpose of this is it is common for parts with internal surfaces. For example the part I'm making today slides over a rectangular support rod and those perimeters will never be seen. I'd like to print a logo on the part, but don't want to produce excess waste.