Yeah; merged a paper texture to the polygons as I recall, Tran. Been a few years since I did this one, but do remember it used that multi-drop shadow script which is very time consuming. Before then, you had to strategically separate the colors into the layers that you then use for the shading step. Have little time to remember exactly how I did this (had to head off to my part time job and did a 5.4 mile mall walk earlier so am quite tired, too; lol). Still, G'MIC's Polygonize (Delauney) is key to creating these.
