gluBeginCurve — delimit a NURBS curve definition

C Specification

void gluBeginCurve(GLUnurbs* nurb);

C Specification

void gluEndCurve(GLUnurbs* nurb);



Specifies the NURBS object (created with gluNewNurbsRenderer).


Use gluBeginCurve to mark the beginning of a NURBS curve definition. After calling gluBeginCurve, make one or more calls to gluNurbsCurve to define the attributes of the curve. Exactly one of the calls to gluNurbsCurve must have a curve type of GLU_MAP1_VERTEX_3 or GLU_MAP1_VERTEX_4. To mark the end of the NURBS curve definition, call gluEndCurve.

GL evaluators are used to render the NURBS curve as a series of line segments. Evaluator state is preserved during rendering with glPushAttrib(GLU_EVAL_BIT) and glPopAttrib(). See the glPushAttrib reference page for details on exactly what state these calls preserve.


The following commands render a textured NURBS curve with normals; texture coordinates and normals are also specified as NURBS curves:

   gluNurbsCurve(nobj, ..., GL_MAP1_TEXTURE_COORD_2);
   gluNurbsCurve(nobj, ..., GL_MAP1_NORMAL);
   gluNurbsCurve(nobj, ..., GL_MAP1_VERTEX_4);

See Also

gluBeginSurface, gluBeginTrim, gluNewNurbsRenderer, gluNurbsCurve, glPopAttrib, glPushAttrib


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