Use Mask define to Material ID

A tool that allows users to convert the active sculpt mask into any other vertex data, including material tags.

Exoside's quadremesher is one of a couple of systems that requires vertex ID control to handle large polycounts more easily. Material groups can be used to control the flow of edge loops, having a quick mask operator to handle this will result in faster workflows in many other cases. This addon is made to replace Zbrush's auto-retopology which also uses different polygroups to define support loops. in zbrush the process of defining groups is as simple as using a mask, it would be nice to have that in Blender.