Page Comparison

...

Allows you to choose the interpolation of the UV coordinates for the new geometry, choosing from (taken from Pixar's specification): 

• None: doesn't perform UV interpolation  No boundary interpolation behavior occurs 
• Edges: interpolates the UV coordinates from the UV coordinates of the nearest edges  All the boundary edge-chains are sharp creases; boundary vertices are not affected 
• Edges and Corners:  interpolates the UV coordinates taking the UV coordinates of both the nearest edges and corners Sharp:All the boundary edge-chains are sharp creases and boundary vertices with exactly two incident edges are sharp corners 
• Sharp: Smooths only near vertices that are not at a discontinuous boundary. All vertices on a discontinuous boundary are subdivided with a sharp rule (interpolated through). 
  
  

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. 

...

Angle between two polygons below which the normals are not smoothed after the subdivision, maintaining their original orientation.