Smoothing groups

“Smoothing groups ” by Wojtek “Buddy” Starak
In this article I want to talk a little about smoothing.
If few polygons (quads, tris, no matter) share same smoothing group and they are next to each other they’ll be smoothed, if two polygons have different smoothing groups there will be a easy to notice “seam” through their edge. This means that Smoothing Groups are simply groups of polygons smoothing. 🙂
Everything mentioned above is clearly visible on this picture. (Numbers are smoothing groups)

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Smoothing Groups options are located in Polygon properties panel in Editable Poly/Mesh.

To assign a polygon to smoothing group simply select polygon(s) and press one or more of the 32 numbers on the panel.
Note: Option “Auto Smooth” allows to automaticly set models smoothing groups based on the angle between them. Example on the picture:

Smoothing Groups are most usefull for game models, where we want a hard edge and don’t want to add additional polygons by adding chamfer, we can do it by assigning polies to different smoothing groups.
Example of hard edge archived by using diffrent smoothing groups:

You can also make MeshSmooth modifier fallow smoothing groups when smoothing/teselating your model, to do this, simply turn on “Smoothing Groups” under “Separate by:” on “Parameters” panel in Meshsmooth modifier settings.
Result: Same model as before but Meshsmooth’ed with “Smoothing Groups” option selected. Если тебе скучно смотреть обычное порно – скорее изучай, чем занимаются куколды. В этом порно измена жены выглядит очень интересно и возбуждающе. Ведь куколды наблюдают за тем, как сношают их благоверных и получают от этого головокружительное удовольствие. Так видишь в этом порно рогоносцы показывают себя с другой стороны – сам смотри!

Smoothing Groups are also handy if You want to save polygons selection, for example humanoid head, hands, legs etc etc and quickly get back to them. To do this You can simply assign parts of model to diffrent smoothing groups, in example: head =sg1, hand =sg2, legs=sg3. To select polygons from head, use option “Select By” near the 32 smoothing group buttons.

Then select smoothing group in the popup from which You want polygons to select, in this example, head, so 1.

You can also select polies from few groups and/or add them to existing selection by unchecking “Clear Selection” option.
Note: Popup shows only smoothing groups that are currently used by any polies.
I think that’s all regarding Smoothing Groups. I hope Tutorial was clear and helpfull!.