Hierarchical Subdivision Surfaces

Hierarchical subdivision surfaces are supported by mental ray versions prior to 3.2 when the mental matter library libmisubdiv.so is linked in. This library implements the Loop subdivision scheme for triangle meshes, and the Catmull-Clark subdivision scheme for quadrilateral meshes. The following features are available with this library:

C/C++ API for subdivision surface construction and manipulation. This API can be used by geometry shaders to create renderable subdivision surface objects.
Smooth, dart, conic, cusp and corner vertex features.
Crease edges with fractional sharpness.
Adaptive local refinement and tessellation, visibility culling.
Texturing with unlimited number of texture spaces, motion blur.
Trim regions by trim edge specification.
Multiresolution editing with wavelet decomposition and variable data-dependent smoothing.
Export of subdivision surfaces to NURBS.

mental ray 3.2 and later have subdivision surface rendering (but not modeling) support built in, and require no external library. Also, mental ray 3.2 performs displacement mapping during computation of the limit surface, using a single approximation setting for the entire tessellation.

home

<< prev

next >>

contents