CompuServe Thread

Hi John, Thanks for the kind words. << I am trying to model a reasonably detailed, seamless skinned hand with fully articulated fingers. I've tried your common cross-section approach (or what I gather is your approach from playing with the branch examples) but I can't get a clean 5 fingered model. >> Hmmm. Hands are very difficult in general, specifically with this approach, & consequently because you're implying close-up shots of the hands – thus it's more difficult to achieve the "misdirection". In fact, the hands for the woman model are not "seamless". << I've tried using more complex control objects but I seem to lose control of the contours and the model looks too angular. Do have any tips that could help? >> When you say "more complex control objects", I assume you mean either more vertices per CS, more CS's, or both. With Skinned objects, the key is in using LESS resolution & less CS's if at all possible. If you skin a simple cylinder with CS's composed of say 16 vertices, it's going to appear more angular than from CS's using just 4 vertices – especially when you raise the resolution/smoothing bias. If you must use higher-res CS's, then you really need to crank the smoothness resolution up, and raise the bias in the direction where you need the smoothness. In general, the seamless branching technique is very similar to lofting with back-tracking paths. Except with individual CS's & Skin, you're doing it in the Editor. To create a hand & fingers, you'd have to start from the wrist with CS's for the hand, then step your CS's down to finger size, create the length of a finger, step the CS's down to close off the fingertip, run yourself a path of CS's INSIDE the skinned finger's surface, come back to finger size inside the hand's skinned surface to start another finger, etc.. You also may need to double or triple CS's at various points along the way to shape the skinned objects. As you can see, with a hand, 4 fingers & a thumb – this just may not be practical or even possible, and still obtain good rendering – especially with a close-up shots. The only other possible approach is to use a spherical template with enough resolution in this case, to literally "pull" your jointed fingers out like taffy. But of course with this method, articulating the hand becomes much more difficult as the hand is not constructed from CS's which can be linked to dummy skeletonal objects for animation purposes….not to mention the very abstract nature of modeling this way. You would have to make numerous morph targets utilizing extensive vertex-level manipulations – but the hand would be seamless <g>. Wish I could offer more, but that's the long & short of it. Regards, BILL

John, The topic of "Seamless Skin" is covered in our new book 3D Studio Special Effects. Martin Foster wrote this chapter. There book shows step-by-step how to create seamless skin. The book comes with a CD-ROM with all of the necessary 3DS files, maps, etc. You will still need to get the Yost Group's IPAS routines, though. ____kevin