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<STRONG>NAME</STRONG>
<STRONG>gluNurbsCurve</STRONG> - define the shape of a NURBS curve
<STRONG>C</STRONG> <STRONG>SPECIFICATION</STRONG>
void <STRONG>gluNurbsCurve</STRONG>( GLUnurbs* <EM>nurb</EM>,
GLint <EM>knotCount</EM>,
GLfloat *<EM>knots</EM>,
GLint <EM>stride</EM>,
GLfloat *<EM>control</EM>,
GLint <EM>order</EM>,
GLenum <EM>type</EM> )
<STRONG>PARAMETERS</STRONG>
<EM>nurb</EM> Specifies the NURBS object (created with
<STRONG>gluNewNurbsRenderer</STRONG>).
<EM>knotCount</EM> Specifies the number of knots in <EM>knots</EM>.
<EM>knotCount</EM> equals the number of control points
plus the order.
<EM>knots</EM> Specifies an array of <EM>knotCount</EM> nondecreasing
knot values.
<EM>stride</EM> Specifies the offset (as a number of single-
precision floating-point values) between
successive curve control points.
<EM>control</EM> Specifies a pointer to an array of control
points. The coordinates must agree with <EM>type</EM>,
specified below.
<EM>order</EM> Specifies the order of the NURBS curve. <EM>order</EM>
equals degree + 1, hence a cubic curve has an
order of 4.
<EM>type</EM> Specifies the type of the curve. If this curve is
defined within a <STRONG>gluBeginCurve</STRONG>/<STRONG>gluEndCurve</STRONG> pair,
then the type can be any of the valid one-
dimensional evaluator types (such as
<STRONG>GL_MAP1_VERTEX_3</STRONG> or <STRONG>GL_MAP1_COLOR_4</STRONG>). Between a
<STRONG>gluBeginTrim</STRONG>/<STRONG>gluEndTrim</STRONG> pair, the only valid
types are <STRONG>GLU_MAP1_TRIM_2</STRONG> and <STRONG>GLU_MAP1_TRIM_3</STRONG>.
<STRONG>DESCRIPTION</STRONG>
Use <STRONG>gluNurbsCurve</STRONG> to describe a NURBS curve.
When <STRONG>gluNurbsCurve</STRONG> appears between a
<STRONG>gluBeginCurve</STRONG>/<STRONG>gluEndCurve</STRONG> pair, it is used to describe a
curve to be rendered. Positional, texture, and color
coordinates are associated by presenting each as a separate
<STRONG>gluNurbsCurve</STRONG> between a <STRONG>gluBeginCurve</STRONG>/<STRONG>gluEndCurve</STRONG> pair. No
more than one call to <STRONG>gluNurbsCurve</STRONG> for each of color,
position, and texture data can be made within a single
<STRONG>gluBeginCurve</STRONG>/<STRONG>gluEndCurve</STRONG> pair. Exactly one call must be
made to describe the position of the curve (a <EM>type</EM> of
<STRONG>GL_MAP1_VERTEX_3</STRONG> or <STRONG>GL_MAP1_VERTEX_4</STRONG>).
When <STRONG>gluNurbsCurve</STRONG> appears between a <STRONG>gluBeginTrim</STRONG>/<STRONG>gluEndTrim</STRONG>
pair, it is used to describe a trimming curve on a NURBS
surface. If <EM>type</EM> is <STRONG>GLU_MAP1_TRIM_2</STRONG>, then it describes a
curve in two-dimensional (<EM>u</EM> and <EM>v</EM>) parameter space. If it is
<STRONG>GLU_MAP1_TRIM_3</STRONG>, then it describes a curve in two-
dimensional homogeneous (<EM>u</EM>, <EM>v</EM>, and <EM>w</EM>) parameter space. See
the <STRONG>gluBeginTrim</STRONG> reference page for more discussion about
trimming curves.
<STRONG>EXAMPLE</STRONG>
The following commands render a textured NURBS curve with
normals:
gluBeginCurve(nobj);
gluNurbsCurve(nobj, ..., GL_MAP1_TEXTURE_COORD_2);
gluNurbsCurve(nobj, ..., GL_MAP1_NORMAL);
gluNurbsCurve(nobj, ..., GL_MAP1_VERTEX_4);
gluEndCurve(nobj);
<STRONG>NOTES</STRONG>
To define trim curves which stitch well, use <STRONG>gluPwlCurve</STRONG>.
<STRONG>SEE</STRONG> <STRONG>ALSO</STRONG>
<STRONG>gluBeginCurve</STRONG>, <STRONG>gluBeginTrim</STRONG>, <STRONG>gluNewNurbsRenderer</STRONG>,
<STRONG>gluPwlCurve</STRONG>
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