glubeginsurface(3G) — IRIX 6.5.3f



gluBeginSurface(3G)            OpenGL Reference            gluBeginSurface(3G)



NAME
     gluBeginSurface, gluEndSurface - delimit a NURBS surface definition


C SPECIFICATION
     void gluBeginSurface( GLUnurbs* nurb )

     void gluEndSurface( GLUnurbs* nurb )


PARAMETERS
     nurb  Specifies the NURBS object (created with gluNewNurbsRenderer).


DESCRIPTION
     Use gluBeginSurface to mark the beginning of a NURBS surface definition.
     After calling gluBeginSurface, make one or more calls to gluNurbsSurface
     to define the attributes of the surface.  Exactly one of these calls to
     gluNurbsSurface must have a surface type of GLMAP2VERTEX3 or
     GLMAP2VERTEX4.  To mark the end of the NURBS surface definition, call
     gluEndSurface.

     Trimming of NURBS surfaces is supported with gluBeginTrim, gluPwlCurve,
     gluNurbsCurve, and gluEndTrim.  Refer to the gluBeginTrim reference page
     for details.

     OpenGL evaluators are used to render the NURBS surface as a set of
     polygons.  Evaluator state is preserved during rendering with
     glPushAttrib(GLEVALBIT) and glPopAttrib(). See the glPushAttrib
     reference page for details on exactly what state these calls preserve.


EXAMPLE
     The following commands render a textured NURBS surface with normals; the
     texture coordinates and normals are also described as NURBS surfaces:


          gluBeginSurface(nobj);
             gluNurbsSurface(nobj, ..., GL_MAP2_TEXTURE_COORD_2);
             gluNurbsSurface(nobj, ..., GL_MAP2_NORMAL);
             gluNurbsSurface(nobj, ..., GL_MAP2_VERTEX_4);
          gluEndSurface(nobj);



SEE ALSO
     gluBeginCurve, gluBeginTrim, gluNewNurbsRenderer, gluNurbsCurve,
     gluNurbsSurface, gluPwlCurve







                                                                        Page 1
Museum
