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GLUNURBSCURVE()                                                GLUNURBSCURVE()

NAME
       gluNurbsCurve - define the shape of a NURBS curve

C SPECIFICATION
       void gluNurbsCurve( GLUnurbs* nurb,
                           GLint knotCount,
                           GLfloat *knots,
                           GLint stride,
                           GLfloat *control,
                           GLint order,
                           GLenum type )

PARAMETERS
       nurb       Specifies the NURBS object (created with
                  gluNewNurbsRenderer).

       knotCount  Specifies the number of knots in knots.  knotCount equals
                  the number of control points plus the order.

       knots      Specifies an array of knotCount nondecreasing knot values.

       stride     Specifies the offset (as a number of single-precision
                  floating-point values) between successive curve control
                  points.

       control    Specifies a pointer to an array of control points. The
                  coordinates must agree with type, specified below.

       order      Specifies the order of the NURBS curve. order equals degree
                  + 1, hence a cubic curve has an order of 4.

       type       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.

DESCRIPTION
       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, texture, and
       color coordinates are associated by presenting each as a separate
       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 trimming curves.

EXAMPLE
       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);

NOTES
       To define trim curves which stitch well, use gluPwlCurve.

SEE ALSO
       gluBeginCurve, gluBeginTrim, gluNewNurbsRenderer, gluPwlCurve

                                                               GLUNURBSCURVE()