# GLUPWLCURVE

Section: Misc. Reference Manual Pages (3G)

Page Index

## NAME

**gluPwlCurve**
- describe a piecewise linear NURBS trimming curve

## C SPECIFICATION

void

**gluPwlCurve**(
GLUnurbs*

*nurb*,

GLint *count*,
GLfloat* *data*,
GLint *stride*,
GLenum *type* )

delim $$

## PARAMETERS

*nurb*-
Specifies the NURBS object (created with
**gluNewNurbsRenderer**).
*count*-
Specifies the number of points on the curve.
*data*-
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 that 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.
See the **gluBeginTrim** reference page for more information
about trimming curves.

## NOTES

To describe a trim curve that closely follows the contours of a NURBS
surface, call

**gluNurbsCurve**.

## SEE ALSO

**gluBeginCurve(3G)**,

**gluBeginTrim(3G)**,

**gluNewNurbsRenderer(3G)**,

**gluNurbsCurve(3G)**