table of contents
GLUBEGINCURVE(3G) | OpenGL Manual | GLUBEGINCURVE(3G) |
NAME¶
gluBeginCurve - delimit a NURBS curve definition
C SPECIFICATION¶
void gluBeginCurve(GLUnurbs* nurb);
C SPECIFICATION¶
void gluEndCurve(GLUnurbs* nurb);
PARAMETERS¶
nurb
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 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.
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(), gluBeginTrim(), gluNewNurbsRenderer(), gluNurbsCurve(), glPopAttrib(), glPushAttrib()
COPYRIGHT¶
Copyright © 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.
AUTHORS¶
opengl.org
04/12/2021 | opengl.org |