OpenSubdiv

This page provides information on the OpenSubdiv attribute set that can be added to meshes.

Overview

The OpenSubdiv group of attributes allows a mesh to be subdivided using the OpenSubdiv library. The main advantage of OpenSubdiv is support for creases. A disadvantage is that OpenSubdiv subdivision is currently uniform and not view-dependent, in contrast to the regular V-Ray subdivision.

UI Path: ||Select mesh|| > Attribute Editor > Attributes menu > VRay > OpenSubdiv

OpenSubdiv Attributes

Render as OpenSubdiv surface – When enabled, the object will be subdivided before rendering using the OpenSubdiv library.

Osd Depth – The number of subdivision levels.

Osd Type – The type of subdivision used. Two types are currently supported by the OpenSubdiv library:

Catmull-Clark – The default subdivision method which can handle meshes with arbitrary polygons (triangles, quads etc);
Loop – This subdivision method works with triangles only.

Osd Preserve Map Borders – Specifies how to handle subdivisions of UV coordinates at UV seams when Osd Subdivide UVs is enabled. The possible values are:

None – UVs are always subdivided regardless of whether they are on a UV seam or not;
Internal – Only preserve UVs if they are on an internal UV seam;
All – Does not subdivide UVs on UV seams.

Osd Subdivide UVs – Allows you to choose whether or not the UVs of the object will be subdivided at the borders.

Osd Preserve geometry borders – Specifies whether geometry borders are preserved or not.

Scripting

References

Official web site of Pixar's OpenSubdiv library: http://graphics.pixar.com/opensubdiv/

Notes

• Color Sets are supported on objects that have openSubdiv attributes from V-Ray 3.3