GLUBEGINCURVE
Section: Misc. Reference Manual Pages (3G)
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NAME
gluBeginCurve, gluEndCurve
- delimit a NURBS curve definition
 
C SPECIFICATION
void gluBeginCurve(
GLUnurbs* nurb )
void gluEndCurve(
GLUnurbs* nurb )
delim $$
 
PARAMETERS
- nurb
- 
Specifies the NURBS object (created with gluNewNurbsRenderer).
DESCRIPTION
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 GL_MAP1_VERTEX_3 or GL_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(GL_EVAL_BIT) and 
glPopAttrib().  
See the glPushAttrib reference page for details on exactly what state
these calls preserve.
 
EXAMPLE
The following commands render a textured NURBS curve with normals;
texture coordinates and normals are also specified as NURBS curves:
gluBeginCurve(nobj);
   gluNurbsCurve(nobj, ..., GL_MAP1_TEXTURE_COORD_2);
   gluNurbsCurve(nobj, ..., GL_MAP1_NORMAL);
   gluNurbsCurve(nobj, ..., GL_MAP1_VERTEX_4);
gluEndCurve(nobj);
 
SEE ALSO
gluBeginSurface(3G), gluBeginTrim(3G), gluNewNurbsRenderer(3G), 
gluNurbsCurve(3G), 
glPopAttrib(3G), glPushAttrib(3G)