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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 )

       delim $$

PARAMETERS
       nurb	  Specifies  the  NURBS	 object	 (created with gluNewNurbsRen-
		  derer).

       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	float-
		  ing-point values) between successive curve control points.

       control	  Specifies a pointer to an array of control points. The coor-
		  dinates 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	gluBe-
		  ginTrim/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()

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