In-depth description of Smooth Grouping
polycounter lvl 18
I am writting docs to make some guidlines for how artists smooth their models. I have a bunch of rules I have learned through expierence but I would like to back up my opinion with facts.
A document on the way smoothing works would be really helpful. Has anyone come across something I can point to as a reference for my findings?
-R
A document on the way smoothing works would be really helpful. Has anyone come across something I can point to as a reference for my findings?
-R
Replies
http://www.poopinmymouth.com/process/tips/smoothing_groups.jpg
This is for max, right? From the help file:
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Smoothing groups define whether a surface is rendered with sharp edges or smooth surfaces.
Smoothing groups are numbers assigned to the faces or patches of an object. Each face or patch can carry any number of smoothing groups up to the maximum of 32. If two faces or patches share an edge and share the same smoothing group, they will render as a smooth surface. If they don't share the same smoothing group, the edge between them will render as a corner.
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also...
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Smoothing groups define whether a surface is rendered with sharp edges or smooth surfaces. Smoothing groups are numbers assigned to the faces of an object. Each face can carry any number of smoothing groups up to the maximum of 32. If two faces share an edge and share the same smoothing group, they render as a smooth surface. If they dont share the same smoothing group, the edge between them renders as a corner. You can manually change or animate smoothing group assignment. Changing smoothing groups does not alter geometry in any way; it only changes the way faces and edges are shaded.
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That last part is not really true when working with games. Every vertex along the hard edge will be duplicated for your in-game model.
When I don't have time, I use smoothing groups. But when I do have time, I create a tight bevel instead... same vertex cost but I get more control over the hardness of the edge. The width of the bevel controls the hardness-softness of the edge. Not so with smoothing groups... you only get on or off really.
One more tip that's helped me... the extra edges (or smoothing groups, you choose) can help your normal map too, in that they help fix some dark shading problems where you have extreme degree-changes in your low-res model.
Autodesk: hard/soft edge assignment, NOW!
Go away smoothing groups!
Autodesk: hard/soft edge assignment, NOW!
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I second that, and I've always been a Max user. Every Maya convert I've ever trained has been like, "WTF is a Smoothing Group?! The EDGE is either hard or soft!". And I just have to nod my head, and say "Yeah, it's stupid, I know."