'\" 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 partialdi
.ds Xs 56621 5 partialdisk.gl
.TH GLUPARTIALDISK 3G
.SH NAME
.B "gluPartialDisk
\- draw an arc of a disk

.SH C SPECIFICATION
void \f3gluPartialDisk\fP(
GLUquadric* \fIquad\fP,
.nf
.ta \w'\f3void \fPgluPartialDisk( 'u
	GLdouble \fIinner\fP,
	GLdouble \fIouter\fP,
	GLint \fIslices\fP,
	GLint \fIloops\fP,
	GLdouble \fIstart\fP,
	GLdouble \fIsweep\fP )
.fi

.EQ
delim $$
.EN
.SH PARAMETERS
.TP \w'\fIslices\fP\ \ 'u 
\f2quad\fP
Specifies a quadrics object (created with \%\f3gluNewQuadric\fP).
.TP
\f2inner\fP
Specifies the inner radius of the partial disk (can be 0).
.TP
\f2outer\fP
Specifies the outer radius of the partial disk.
.TP
\f2slices\fP
Specifies the number of subdivisions around the \f2z\fP axis.
.TP
\f2loops\fP
Specifies the number of concentric rings about the origin into which
the partial disk is subdivided.
.TP
\f2start\fP
Specifies the starting angle, in degrees, of the disk portion.
.TP
\f2sweep\fP
Specifies the sweep angle, in degrees, of the disk portion.
.SH DESCRIPTION
\%\f3gluPartialDisk\fP renders a partial disk on the $ z ~=~ 0 $ plane. A partial disk is 
similar to a full disk, except that only the subset of the disk from
\f2start\fP through \f2start\fP + \f2sweep\fP is included (where 0 degrees is along the 
+\f2y\f axis,
90 degrees along the +\f2x\fP axis, 180 degrees along the \-\f2y\fP axis, and 
270 degrees along the \-\f2x\fP axis).
.P
The partial disk has a radius of 
\f2outer\fP, and contains a concentric circular hole with a radius 
of \f2inner\fP. If \f2inner\fP is 0, then no hole is generated. The partial disk is
subdivided around the \f2z\fP axis into slices (like pizza slices), and also
about the \f2z\fP axis into rings 
(as specified by \f2slices\fP and \f2loops\fP, respectively).
.P
With respect to orientation, the +\f2z\fP 
side of the partial disk is considered to 
be outside (see \%\f3gluQuadricOrientation\fP).
This means that if the 
orientation is set to \%\f3GLU_OUTSIDE\fP, then any normals generated 
point along the +\f2z\fP axis. Otherwise, they point along the \-\f2z\fP 
axis.
.P
If texturing is turned on (with \%\f3gluQuadricTexture\fP), texture
coordinates are generated
linearly such that where $ r ~=~ "outer" $, the value at (\f2r\fP, 0, 0) is 
(1.0, 0.5), at (0, \f2r\fP, 0) it is (0.5, 1.0), at (\-\f2r\fP, 0, 0) 
it is (0.0, 0.5), and 
at (0, \-\f2r\fP, 0) it is (0.5, 0.0).
.SH SEE ALSO
\%\f3gluCylinder(3G)\fP, \%\f3gluDisk(3G)\fP, \%\f3gluNewQuadric(3G)\fP, \%\f3gluQuadricOrientation(3G)\fP,
\%\f3gluQuadricTexture(3G)\fP, 
\%\f3gluSphere(3G)\fP