To refine and smooth a selection of faces in a PolyMesh surface using Catmull-Clark subdivision surfaces.
Although it is similar to Subdivision Surface, this modeling tool only acts on a part of a Polymesh object instead of the entire one.
This modeling tool is a modifier, not an action; therefore it does not feature a construction tree.
How to use
1. Select a single polymesh object.
2. Click the Subdivision surface on faces icon or choose the Tools > PolyMesh > Subdivision surface on faces command.
3. If the original object is a part of a Construction Tree an alert panel warns you: The selected PolyMesh is part of a Construction Tree. In order to edit with this Modeling Tool, the PolyMesh needs not to be a part of the Construction Tree. Do you want the PolyMesh to be set as hidden and a copy to be created for editing?
4. If you click Yes, a new polygonal model with the same shape of the selected one is created.
5. Select the faces you want to smooth.
6. Adjust the parameters in the Modeling Tool panel and click the button Go to apply the action.
Options
Go
To apply the command with the specified parameters.
Modeling Tool panel. Just click on the button Go.
View
To view and select either the faces to be smoothed or their edges. Edges selection can be used to assign a weight to edges (see Edge weight parameter). Faces and edges can be viewed only in Edit Mode.
Modeling Tool panel. Just switch on the View faces or the View edges radio buttons.
Iterations
To adjust the subdivision of a polygonal model. The higher the iterations number, the smoother will be the resulting surface.
Modeling Tool panel. Set the value either by moving the slider or by typing it in the data field and pressing Enter.
Note: The subdivision computation is memory expensive, so be careful not to increase the iterations number too much.
Edge weight
To adjust the weight of one or more edges of a polymesh.
Modeling Tool panel. Choose the Edit Mode and the option View edges of the View parameter. Select the edge or edges whose weight factor you want to modify. Move the slider or type the weight in the Weight data field. Press Enter to confirm. Default factor is 0. While the maximum weight factor is 10. The more you increase this value, the greater the pulling effect that the edge exerts on the polymesh model.
LetÃs see an application example: faces to be smoothed are selected. The edges that have to be sharp are selected and weighted (edge weight = 10).
Then, two iteration are applied to selected faces and a part of the result is selected again to obtain a further refinement.
Other two iterations are applied to the top part of the object. The result is an object built with various degrees of detail.