Surface - NURB Surface

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NURB Surface

Page Contents

Description

Navigation

Controls

Application Notes

•Surface deformations

Related Topics

Description

This feature allows creation of a NURB surface.

Navigation

This feature can be accessed by selecting NURB Surface (Non-Uniform Rational B-Spline surface in U,V parameters) as the surface type on the Surface tab of a surface dialog box.

Controls

Control	Inputs / Description	Defaults
Logical Parent	Name of Parent entity.	Custom Element Name
Name	Name of surface supplied by user.	Surf n
Description	Description of the surface.
Traceable	Surface can be raytraced.	Checked
Use for trimming only	Never raytrace. Surface used for trimming only.	Unchecked
Type	Surface type.	NURB
Surface Parameters
UV Degree	Polynomial degree	blank
UV knots (Value/Range)	Knot values and Active Range.	0-360
Control Points/weights	Each control point has an x,y,z position and a weight. For the purposes of optimization, configurations and scripting, control points can be indexed in two different ways. Single Indexing If there are N control points, a control point can have index from 0 to N-1. The single index value is shown on the left side of the "Term (i,j)" column in the GUI for each control point row. 2D Indexing Each control point corresponds to a specific (i,j) index pair of the NURB function. The 2D index value is shown on the right side of the "Term (i,j)" column in the GUI for each control point row.

OK	Accept settings and close dialog box.
Cancel	Discard settings and close dialog box.
Apply	Accept settings and keep dialog box open.
Help	Access this Help page.

Application Notes

Surface deformation

The NURB surface type is a "non-sagable" surface and therefore cannot be used as a deforming surface. A "sagable" surface is defined as single-valued in z.