GLUBEGINSURFACE(3G) GLUBEGINSURFACE(3G)

gluBeginSurface, gluEndSurface - delimit a NURBS surface definition

void gluBeginSurface( GLUnurbs* nurb )



void gluEndSurface( GLUnurbs* nurb )













  

  
Specifies the NURBS object (created with gluNewNurbsRenderer).










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 GL_MAP2_VERTEX_3 or GL_MAP2_VERTEX_4. To mark the end
    of the NURBS surface definition, call gluEndSurface.


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


GL evaluators are used to render the NURBS surface as a set of
    polygons. 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.








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);










gluBeginCurve, gluBeginTrim,
    gluNewNurbsRenderer, gluNurbsCurve, gluNurbsSurface,
    gluPwlCurve