Mesh Local Subdivision Op Property Editor

 
 
 

Refines selected polygons on a polygon mesh object using a subdivision surface algorithm.

To apply: Select one or more polygons on a polygon mesh, then choose Modify Poly. Mesh Local Subdivision Refinement from the Model toolbar.

To redisplay: Select the polygon mesh, click the Selection button on the Select panel, then click the Mesh Local Subdivision Op icon.

Level

Number of times that the subdivision process is iterated. Higher levels provide for greater detail and smoothness but result in heavier geometries and longer processing.

Each iteration increases the number of polygons, which can result in very dense and heavy geometry.

Rule

The mathematical method for calculating the subdivisions:

  • Catmull-Clark produces rounded shapes. The generated polygons are all quadrilateral. The higher the Subdivision Depth, the more this method approximates a bicubic standard B-spline surface. At regular vertices (exactly four edges), the surface has C2 (curvature) continuity; in other areas, the surface has C1 (tangential or parametric) continuity.

  • Doo-Sabin produces shapes that follow the original mesh more closely than Catmull-Clark. At each iteration, every polygon generates one similar polygon, every edge generates a new quadrilateral polygon, and every vertex generates a polygon with the same number of edges as were connected to the vertex. The higher the Subdivision Level, the more this method approximates a biquadratic uniform B-spline surface. At regular vertices, the surface has C1 (tangential or parametric) continuity; in other areas, the surface has G1 continuity (i.e., the tangents have the same direction but not necessarily the same length). This method does not correctly propagate clusters and cluster properties, and it does not handle creases very well.