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- None: No boundary interpolation behavior occurs
- Edges: a All the boundary edge-chains are sharp creases; boundary vertices are not affected
- Edges and Corners: all All the boundary edge-chains are sharp creases and boundary vertices with exactly two incident edges are sharp corners
- Sharp: Smooths faces varying the values only near vertices that are not at a discontinuous boundary; all . All vertices on a discontinuous boundary are subdivided with a sharp rule (interpolated through). This mode is designed to be compatible with ZBrush and Maya's "smooth internal only" interpolation.
Edge Crease
When set to 0, the polygon is divided evenly at the middle of its length. A higher value approximates the new edge to the original edge, concentrating the subdivision near the edge. This setting is useful to bevel the edges of the model.
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