NAME¶

gluBeginCurve, gluEndCurve - delimit a NURBS curve definition

C SPECIFICATION¶

void gluBeginCurve( GLUnurbs* nurb )

void gluEndCurve( GLUnurbs* nurb )

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)