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Zbrush to Mantra displacement June 22, 2017, 9:30 a.m.

McNistor
Yea, thanks. I'm hoping the info in this thread will pile up, because I don't, by any means, live under the impression that what I did here is a comprehensive analysis on what goes into Mantra's dealing with geometry generation at render time, either from an optimization pov or a looks one. In order to get there, this thread will have to wait for me to become a Mantra expert or to have other users chip in with their knowledge and practical results.
I know the user base in general is not focused on this type of work, but I'm sure there a few out there and I'm hoping they'll take notice and respond.

Imho, generally you'll want to use render time subdivision, and better dicing quality if first option is not enough (both are under parameters of your geometry). That's, well, generally. Mantra seems to be using a sort of Renderman style, render time tessellation, so if mesh is not tessellated enough, it can't place the texture. That's how for example 3delight is working, but, while with 3delight plugin for Softimage, two or three parameters are enough for pleasant life (together with built-in automatic texture conversion), and error is just a blurred image - in Mantra, there are much more parameters able to do something wrong, object local and global render options. For example I'm not sure is there a way to get MIP mapping from external tifs, or there's always necessary to manually convert to RAT.

Not an answer, anyway somehow I got a habit to avoid any bitmap input in H, except environment texture. Good luck.

Surface Loft like SI? May 29, 2017, 6:45 p.m.

Aizatulin
Hi,
something like this maybe?
Nah, this is closer, but H has some strange behavior to add the ‘refinement’ over existing surace, not to rebuild it from scratch. You see it when converting to mesh. Theoretically it's nurbs chord length reparametrization that should work (that's Basis SOP in H), but somehow in 3d apps this makes uniform distribution only for textures, UV and so on, not for possible conversion/tessellation into mesh. Btw, even distribution in Maya belongs to conversion/tessellation into mesh, it's not ‘pure’ nurbs functionality. While H Convert SOP doesn't seem to have such, ‘even’ option. Anyway shouldn't be a big deal to build HDA from Carve-Resample method.

Surface Loft like SI? May 29, 2017, 3:05 p.m.

McNistor
the issue presented here is rather esoteric/theoretical so I'm curios in what scenario you requite this setup. Has this anything to do with custom muscles/skin deformers? Again, pure curiosity…
If we are talking about ‘uniform distribution’, I'm using this option regularly for hard surface, and btw Maya has a few additional options, to convert u or v of nurbs separately, making it possible to keep the original cross section, and even distribution along loft or anything else nurbs. First pic is Maya screenshot, I'd believe the advantage is obvious (easier to combine shapes, also it's good for applying vertex colors, in Maya or H).
However, don't see the short, SOP only way to that in H, except to use Carve SOP, resample curves and re-loft. Maybe I'm out of inspiration anyway.