**gluPwlCurve**

### NAME

**gluPwlCurve** -- describe a piecewise linear NURBS trimming curve
### C SPECIFICATION

void **gluPwlCurve**(GLUnurbsObj **nobj*,
GLint *count*,
GLfloat **array*,
GLint *stride*,
GLenum *type*)

### PARAMETERS

*nobj*-
Specifies the NURBS object (created with
**gluNewNurbsRenderer**).

*count*-
Specifies the number of points on the curve.

*array*-
Specifies an array containing the curve points.

*stride*-
Specifies the offset (a number of single-precision floating-point values)
between points on the curve.

*type*-
Specifies the type of curve. Must be either
**GLU_MAP1_TRIM_2** or
**GLU_MAP1_TRIM_3**.

### DESCRIPTION

**gluPwlCurve** describes a piecewise linear trimming curve for a NURBS
surface. A piecewise linear curve consists of a list of coordinates of points in
the parameter space for the NURBS surface to be trimmed. These points are
connected with line segments to form a curve. If the curve is an approximation
to a curve which is not piecewise linear, the points should be close enough in
parameter space that the resulting path appears curved at the resolution used
in the application.
If type is **GLU_MAP1_TRIM_2**, then it describes a curve in two-dimensional
(*u* and *v*) parameter space. If it is **GLU_MAP1_TRIM_3**, then
it describes a curve in two-dimensional homogeneous (*u*, *v*, and
*w*) parameter space. Please refer to the
**gluBeginTrim** reference page for more
information about trimming curves.

### NOTES

To describe a trim curve which closely follows the contours of a NURBS surface
use **gluNurbsCurve**.
### SEE ALSO

**gluBeginCurve**,
**gluBeginTrim**,
**gluNewNurbsRenderer**,
**gluNurbsCurve**

back to the **OpenGL index page**

© *1995 Uwe Behrens All rights reserved*