_C_ License Applicability. Except to the extent portions of this file are
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_C_ Software License B, Version 1.1 (the "License"), the contents of this
_C_ file are subject only to the provisions of the License. You may not use
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_C_ Original Code. The Original Code is: OpenGL Sample Implementation,
_C_ Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
_C_ Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
_C_ Copyright in any portions created by third parties is as indicated
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_C_ Additional Notice Provisions: The application programming interfaces
_C_ established by SGI in conjunction with the Original Code are The
_C_ OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
_C_ April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
_C_ 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
_C_ Window System(R) (Version 1.3), released October 19, 1998. This software
_C_ was created using the OpenGL(R) version 1.2.1 Sample Implementation
_C_ published by SGI, but has not been independently verified as being
_C_ compliant with the OpenGL(R) version 1.2.1 Specification.
_C_
_C_ $Date: 2004/03/14 08:29:09 $ $Revision: 1.1.1.4 $
_C_ The first character in this file must be an '_'!
_C_ Anything on a line after _C_ is ignored
_define(_filters,eqn)_C_
_C_      eqn is automatically replaced with neqn for nroff
_header(LoadSamplingMatrices, load NURBS sampling and culling matrices)
_names(LoadSamplingMatrices)
.EQ
delim $$
.EN
.SH PARAMETERS
_phead(_param1)
Specifies the NURBS object (created with _cmnd(NewNurbsRenderer)).
_phead(_param2)
Specifies a modelview matrix (as from a _glcmnd(GetFloatv) call).
_phead(_param3)
Specifies a projection matrix (as from a _glcmnd(GetFloatv) call).
_phead(_param4)
Specifies a viewport (as from a _glcmnd(GetIntegerv) call).
.SH DESCRIPTION
_cmnd uses _param2, _param3, and _param4 to recompute the sampling and culling 
matrices stored in _param1.
The sampling matrix determines how finely a NURBS curve or surface
must be tessellated to satisfy the sampling tolerance (as determined by the
_gluconst(SAMPLING_TOLERANCE) property).
The culling matrix is used in deciding if a NURBS curve or surface
should be culled before 
rendering (when the _gluconst(CULLING) property is turned on).
.P
_cmnd is necessary only if the _gluconst(AUTO_LOAD_MATRIX) property is turned
off (see _cmnd(NurbsProperty)).
Although it can be convenient to leave the _gluconst(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.)
.SH SEE ALSO
_cmnd(GetNurbsProperty),
_cmnd(NewNurbsRenderer),
_cmnd(NurbsProperty)