Sorry for my bad English and the confusing question. I used max to make some models and export as obj by the max to obj plugin, then import into poser. I dont care the edges sharp or not, I just dont want to have the black color as shown in no.1. The no.1 cylinder is a primitive cylinder I made from max, and I got the black color. So if poser cant smooth a 90degree edge, I need to use uvmapper to 'split vertices' to every model that I want to use in poser?