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Trying to Untangle CAD / Sub-D Workflow...

Question asked by Sloan Anderson on Jan 29, 2016
Latest reply on Jan 29, 2016 by Chris Dordoni

Hello all,


I'm curious if anybody out there has found an "ideal" solution for somewhat seamlessly collaborating between folks in a CAD environment and those using 3D / sub-D packages like 3DS Max or Maya? We have countless scenarios where, either:


a). I'll create a CAD file for a new product, that then needs to then be manipulated/presented in something like Max + VRay for high-end rendering, marketing, animation, etc. I use KeyShot on my end, but often this type of work is handed off to the Art Department, and thus translation from CAD to clean sub-d data becomes essential (and also pretty much impossible, from what I've seen). Sure, 3DS Max (surprisingly) supports opening Sldprt/IGES files-- referred to as "Body Objects"-- but if you try to collapse them to usable geometry, they're just broken into very messy, tesselated/triangulated meshes identical to that of an STL/OBJ export from SW. So naturally, this ultimately leads to the Art Department having to remodel the part from scratch--using the tesselated geometry as a starting point-- to achieve the necessary clean, edge-looped, quad-based topology that better lends itself to UVW unwrapping, texturing, lighting, animation, etc. I hate this because what they remodel then becomes an "interpretation" of an otherwise true-to-spec part, leaving a massive margin of error.


b). On the opposite end of the spectrum, SolidWorks' surface tools are still somewhat hit-or-miss compared to other packages, and when dealing with highly organic surfaces or objects (i.e., humanoid figures, etc.) it's far easier to model them in an art/sub-d package vs. CAD. Thankfully, I have found a decent solution in this scenario: TSplines / TS Elements. It's surgically precise when shown shaded without edges, but of course when you go to show edges, it's a complete mess. Definitely not something that lends itself all that well to editing/modifying, but I'll take what I can get-- assuming there's not a better option for this out there? SW's native 'Scan to 3D' is a joke for anything with any degree of complexity, unfortunately...


I have spent countless hours browsing the web far and wide, as well as these forums, all to no avail. However, I do have a few "leads" and curious if anybody can help or chime in; maybe we can treat this as an ongoing thread for anybody else trying to establish a similar pipeline? Here's what I've found so far, for a):


*Rhino 3D-- Thankfully, we have a copy floating around the building and I was able to play with its export tools. I have run countless tests using its OBJ exporter/options/variables, but none of them really interpolate the geometry all that logically. It's still a mess and inconsistent, and despite options claiming to do so: true quad-output doesn't work. There are a number of online converters, etc., that pretty much mirror these export options, still no quads...


*Modo-- This package also natively supports Sldprt files, and does a fair job of interpolating the geometry, but still strictly outputs as tri's vs. quads, which inevitably creates strange seams and pinch points where thousands of triangles might converge around fillets, indents, etc.


*ZBrush-- From what I can gather, the real term we're looking for is "Retoplogize" -- most 3D packages have this capability, but it still must be done manually which can take days for complex geometry (might as well remodel in Max at that point). The only one I've heard of that seems to successfully do this automatically is ZBrush, and of course I don't have a copy. Has anybody tried it? If it works, the Art Department would gladly add it to their arsenal.


This is getting long, but I've also tried MeshLab, SimLab Composer, Okino PolyTrans, etc., but they all do about the same job Rhino does.


I'm dying here.................anyone?