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doc/gl-docs/GLU/disk.3gl

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+'\" 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 disk.gl -
+.ds Xs 8360 4 disk.gl
+.TH GLUDISK 3G
+.SH NAME
+.B "gluDisk
+\- draw a disk
+
+.SH C SPECIFICATION
+void \f3gluDisk\fP(
+GLUquadric* \fIquad\fP,
+.nf
+.ta \w'\f3void \fPgluDisk( 'u
+	GLdouble \fIinner\fP,
+	GLdouble \fIouter\fP,
+	GLint \fIslices\fP,
+	GLint \fIloops\fP )
+.fi
+
+.EQ
+delim $$
+.EN
+.SH PARAMETERS
+.TP \w'\fIslices\fP\ \ 'u 
+\f2quad\fP
+Specifies the quadrics object (created with \%\f3gluNewQuadric\fP).
+.TP
+\f2inner\fP
+Specifies the inner radius of the disk (may be 0).
+.TP
+\f2outer\fP
+Specifies the outer radius of the 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 disk is subdivided.
+.SH DESCRIPTION
+\%\f3gluDisk\fP renders a disk on the \f2z\fP = 0 plane. The 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 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 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 has been turned on (with \%\f3gluQuadricTexture\fP), 
+texture coordinates are generated
+linearly such that where $ r ~=~ "outer" $, the value at (\f2r\fP, 0, 0) is 
+(1, 0.5), at (0, \f2r\fP, 0) it is (0.5, 1), at (\-\f2r\fP, 0, 0) 
+it is (0, 0.5), and 
+at (0, \-\f2r\fP, 0) it is (0.5, 0).
+.SH SEE ALSO
+\%\f3gluCylinder(3G)\fP, \%\f3gluNewQuadric(3G)\fP, \%\f3gluPartialDisk(3G)\fP, 
+\%\f3gluQuadricOrientation(3G)\fP, 
+\%\f3gluQuadricTexture(3G)\fP, \%\f3gluSphere(3G)\fP