loadsamplingmatrices.3gl   [plain text]

'\" e
'\"! eqn | mmdoc
'\"macro stdmacro
.ds Vn Version 1.2
.ds Dt 6 March 1997
.ds Re Release 1.2.0
.ds Dp May 02 11:53
.ds Dm :37 loadsamp
.ds Xs 25465 4 loadsamplingmatrices.gl
.TH GLULOADSAMPLINGMATRICES 3G
.SH NAME
.B "gluLoadSamplingMatrices
\- load NURBS sampling and culling matrices

.SH C SPECIFICATION
void \f3gluLoadSamplingMatrices\fP(
GLUnurbs* \fInurb\fP,
.nf
.ta \w'\f3void \fPgluLoadSamplingMatrices( 'u
	const GLfloat \fI*model\fP,
	const GLfloat \fI*perspective\fP,
	const GLint \fI*view\fP )
.fi

.EQ
delim $$
.EN
.SH PARAMETERS
.TP \w'\fIperspective\fP\ \ 'u 
\f2nurb\fP
Specifies the NURBS object (created with \%\f3gluNewNurbsRenderer\fP).
.TP
\f2model\fP
Specifies a modelview matrix (as from a \f3glGetFloatv\fP call).
.TP
\f2perspective\fP
Specifies a projection matrix (as from a \f3glGetFloatv\fP call).
.TP
\f2view\fP
Specifies a viewport (as from a \f3glGetIntegerv\fP call).
.SH DESCRIPTION
\%\f3gluLoadSamplingMatrices\fP uses \f2model\fP, \f2perspective\fP, and \f2view\fP to recompute the sampling and culling 
matrices stored in \f2nurb\fP.
The sampling matrix determines how finely a NURBS curve or surface
must be tessellated to satisfy the sampling tolerance (as determined by the
\%\f3GLU_SAMPLING_TOLERANCE\fP property).
The culling matrix is used in deciding if a NURBS curve or surface
should be culled before 
rendering (when the \%\f3GLU_CULLING\fP property is turned on).
.P
\%\f3gluLoadSamplingMatrices\fP is necessary only if the \%\f3GLU_AUTO_LOAD_MATRIX\fP property is turned
off (see \%\f3gluNurbsProperty\fP).
Although it can be convenient to leave the \%\f3GLU_AUTO_LOAD_MATRIX\fP
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
\%\f3gluGetNurbsProperty(3G)\fP,
\%\f3gluNewNurbsRenderer(3G)\fP,
\%\f3gluNurbsProperty(3G)\fP