Support eraser tool

Currently we need to either draw a box or individually pick points for removal. It would be nice to have a “brush” type eraser tool with adjustable diameter to clear areas that we need to have clear “like mold surfaces”

This same scheme could also be used to add supports at a set density.

Bonus points if the support removal brush is in the form of a pac-man and can be controlled by the mouse and/or keyboard.