# SoNurbsSurface.3iv man page

SoNurbsSurface ā NURBS surface shape node

## Inherits from

SoBase > SoFieldContainer > SoNode > SoShape > SoNurbsSurface

## Synopsis

**#include <Inventor/nodes/SoNurbsSurface.h>**

Fields from class SoNurbsSurface:

**SoSFInt32 numUControlPoints**

**SoSFInt32 numVControlPoints**

**SoSFInt32 numSControlPoints**

**SoSFInt32 numTControlPoints**

**SoMFFloat uKnotVector**

**SoMFFloat vKnotVector**

**SoMFFloat sKnotVector**

**SoMFFloat tKnotVector**

Methods from class SoNurbsSurface:

**SoNurbsSurface()**

**static SoType getClassTypeId()**

Methods from class SoNode:

**void setOverride(SbBool state)**

**SbBool isOverride() const**

**SoNode * copy(SbBool copyConnections = FALSE) const**

**virtual SbBool affectsState() const**

**static SoNode * getByName(const SbName &name)**

**static int getByName(const SbName &name, SoNodeList &list)**

Methods from class SoFieldContainer:

**void setToDefaults()**

**SbBool hasDefaultValues() const**

**SbBool fieldsAreEqual(const SoFieldContainer *fc) const**

**void copyFieldValues(const SoFieldContainer *fc, SbBool copyConnections = FALSE)**

**SbBool set(const char *fieldDataString)**

**void get(SbString &fieldDataString)**

**virtual int getFields(SoFieldList &resultList) const**

**virtual SoField * getField(const SbName &fieldName) const**

**SbBool getFieldName(const SoField *field, SbName &fieldName) const**

**SbBool isNotifyEnabled() const**

**SbBool enableNotify(SbBool flag)**

Methods from class SoBase:

**void ref()**

**void unref() const**

**void unrefNoDelete() const**

**void touch()**

**virtual SoType getTypeId() const**

**SbBool isOfType(SoType type) const**

**virtual void setName(const SbName &name)**

**virtual SbName getName() const**

## Description

This shape node represents a NURBS surface based on the node's knot vectors and on control points constructed from the current coordinates. The current coordinates are used in row-major order (the V direction corresponds to the rows). The number of coordinates used is determined by the **numUControlPoints** and **numVControlPoints** fields. The **uKnotVector** and **vKnotVector** fields contain floating point arrays of non-decreasing values.

The order of the surface in the U and V directions is defined as the number of knots minus the number of control points in the particular direction. The largest order allowed for a NURBS surface is 8.

The control points of the NURBS surface are transformed by the current cumulative transformation. The surface is drawn with the current light model and drawing style. The coordinates, normals, and texture coordinates of a surface are generated, so you cannot bind explicit normals or texture coordinates to a NURBS surface. The first material in the state is applied to the entire surface.

The surface is trimmed according to the currently defined profile's curves.

When default texture coordinates are applied to a NURBS surface, the edges of the texture square are stretched to fit the surface. The axes of the texture are called S and T; S is horizontal and T is vertical. The axes of the NURBS surface are called U and V; U is horizontal and V is vertical. You can also define texture coordinates explicitly with the S,T location point, the knot vectors, and the current texture coordinates.

The approximation of the surface by polygons is affected by the current complexity value.

## Fields

**SoSFInt32 numUControlPoints**

**SoSFInt32 numVControlPoints**

Number of control points in the U and V directions.

**SoSFInt32 numSControlPoints**

**SoSFInt32 numTControlPoints**

Number of control points in the S and T directions.

**SoMFFloat uKnotVector**

**SoMFFloat vKnotVector**

The knot vectors in the U and V directions.

**SoMFFloat sKnotVector**

**SoMFFloat tKnotVector**

The knot vectors in the S and T directions.

## Methods

**SoNurbsSurface()**

Creates a NURBS surface node with default settings.

**static SoType getClassTypeId()**

Returns type identifier for this class.

## Action Behavior

**SoGLRenderAction**

Draws the surface based on the current coordinates, material, and so on.

**SoRayPickAction**

Picks the surface based on the current coordinates and transformation.

**SoGetBoundingBoxAction**

Computes the bounding box that encloses all control points of the surface with the current transformation applied to them. Sets the center to the average of the control points.

**SoCallbackAction**

If any triangle callbacks are registered with the action, they will be invoked for each successive triangle approximating the surface.

## File Format/Defaults

NurbsSurface { numUControlPoints 0 numVControlPoints 0 numSControlPoints 0 numTControlPoints 0 uKnotVector 0 vKnotVector 0 sKnotVector 0 tKnotVector 0 }

## See Also

**SoIndexedNurbsSurface, SoNurbsCurve, SoProfile**