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.
Since V-Ray Next, Update 2 V-Ray subdivision preserves edge and vertex creases. Compared to using OpenSubdiv, V-Ray subdivision renders faster and requires less memory.
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.
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