gluNurbsCurve()gluNurbsCurve()NAMEgluNurbsCurve - define the shape of a NURBS curve
GLenum type );
Specifies the NURBS object (created with gluNewNurbsRenderer()). Spec‐
ifies the number of knots in knots. knotCount equals the number of
control points plus the order. Specifies an array of knotCount nonde‐
creasing knot values. Specifies the offset (as a number of single-pre‐
cision floating-point values) between successive curve control points.
Specifies a pointer to an array of control points. The coordinates must
agree with type, specified below. Specifies the order of the NURBS
curve. order equals degree + 1, hence a cubic curve has an order of 4.
Specifies the type of the curve. If this curve is defined within a
gluBeginCurve()/gluEndCurve() pair, then the type can be any of the
valid one-dimensional evaluator types (such as GL_MAP1_VERTEX_3 or
GL_MAP1_COLOR_4). Between a gluBeginTrim()/gluEndTrim() pair, the only
valid types are GLU_MAP1_TRIM_2 and GLU_MAP1_TRIM_3.
Use gluNurbsCurve() to describe a NURBS curve.
When gluNurbsCurve() appears between a gluBeginCurve()/gluEndCurve()
pair, it is used to describe a curve to be rendered. Positional, tex‐
ture, and color coordinates are associated by presenting each as a sep‐
arate gluNurbsCurve() between a gluBeginCurve()/gluEndCurve() pair. No
more than one call to gluNurbsCurve() for each of color, position, and
texture data can be made within a single gluBeginCurve()/gluEndCurve()
pair. Exactly one call must be made to describe the position of the
curve (a type of GL_MAP1_VERTEX_3 or GL_MAP1_VERTEX_4).
When gluNurbsCurve() appears between a gluBeginTrim()/gluEndTrim()
pair, it is used to describe a trimming curve on a NURBS surface. 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 discussion about trim‐
To define trim curves which stitch well, use gluPwlCurve().
The following commands render a textured NURBS curve with normals:
gluNurbsCurve(nobj, ..., GL_MAP1_TEXTURE_COORD_2);
gluNurbsCurve(nobj, ..., GL_MAP1_NORMAL);
gluNurbsCurve(nobj, ..., GL_MAP1_VERTEX_4); gluEndCurve(nobj);
SEE ALSOgluBeginCurve(3), gluBeginTrim(3), gluNewNurbsRenderer(3), gluPwl‐