In other words, when you loop through every polygon in the mesh getting edge lengths, keep track of the longest one found.  Then inside polyregs() where you call increase_box(), use that value to grow those regions.

Cinema4D Plugins (Home of Riptide, Riptide Pro, Undertow, Morph Mill, KyamaSlide and I/Ogre plugins) Poser products Freelance Modelling, Poser Rigging, UV-mapping work for hire.