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GLULOADSAMPLINGMATRICES(3G)                                                      GLULOADSAMPLINGMATRICES(3G)



NAME
       gluLoadSamplingMatrices - load NURBS sampling and culling matrices


C SPECIFICATION
       void gluLoadSamplingMatrices( GLUnurbs* nurb,
                                     const GLfloat *model,
                                     const GLfloat *perspective,
                                     const GLint *view )


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

       model        Specifies a modelview matrix (as from a glGetFloatv call).

       perspective  Specifies a projection matrix (as from a glGetFloatv call).

       view         Specifies a viewport (as from a glGetIntegerv call).

DESCRIPTION
       gluLoadSamplingMatrices  uses  model,  perspective,  and  view  to recompute the sampling and culling
       matrices stored in nurb.  The sampling matrix determines how finely a NURBS curve or surface must  be
       tessellated to satisfy the sampling tolerance (as determined by the GLU_SAMPLING_TOLERANCE property).
       The culling matrix is used in deciding if a NURBS curve or surface should be culled before  rendering
       (when the GLU_CULLING property is turned on).

       gluLoadSamplingMatrices  is  necessary  only  if the GLU_AUTO_LOAD_MATRIX property is turned off (see
       gluNurbsProperty).  Although it can be convenient to leave the GLU_AUTO_LOAD_MATRIX  property  turned
       on,  there  can  be  a performance penalty for doing so.  (A round trip to the GL server is needed to
       fetch the current values of the modelview matrix, projection matrix, and viewport.)

SEE ALSO
       gluGetNurbsProperty(3G), gluNewNurbsRenderer(3G), gluNurbsProperty(3G)




                                                                                 GLULOADSAMPLINGMATRICES(3G)