The ToNURBS command converts mesh objects and SubD objects/edges to NURBS surfaces or curves. It can also convert simple objects to NURBS for programs that only read NURBS. For example, Extrusion object is one of the simple object types. It is defined only by a profile curve and a length.
The ToNURBS command replaces:
Hold down Shift+Ctrl and click mesh or SubD edges. Double-click to select an edge loop.
The NURBS object will replace the non-NURBS object.
The NURBS object will simply be added on the current layer. Both the old and new objects will be in the same location.
Click to set the options only used for mesh to NURBS conversion.
Mesh triangles will be replaced by trimmed NURBS surfaces.
Mesh triangles will be replaced by untrimmed NURBS surfaces.
Click to set the options only used for SubD to NURBS conversion.
Specifies if quad face grids will be merged when converting a SubD into a polysurface.
Merges a quad face grid into a larger NURBS surface.
Creates a NURBS surface from each quad SubD face.
Continuity on a SubD at extraordinary vertices is G2. When the ToNURBS command converts a SubD into a polysurface, extraordinary vertices can only be approximated. This option controls the continuity of the polysurface near extraordinary vertices. Away from extraordinary vertices, the polysurface is always G2 on smooth SubD regions.
Makes position continuity near extraordinary vertices. The polysurface is as close as possible to the SubD.
Makes tangent continuity near extraordinary vertices. The polysurface deviates from the SubD a bit more than G0.
Makes curvature continuity near extraordinary vertices. The polysurface deviates from the SubD a bit more than G1.
Forcing G2 may add bulges or dents to the polysurface around extraordinary vertices.
For more information, see Rhino SubD Project.
Rhinoceros 7 © 2010-2021 Robert McNeel & Associates. 23-Jul-2021