GLUPARTIALDISK(3G) UNIX Programmer's Manual GLUPARTIALDISK(3G)

## NAME

**gluPartialDisk** - draw an arc of a disk

## C SPECIFICATION

void **gluPartialDisk**( GLUquadric* *quad*,
GLdouble *inner*,
GLdouble *outer*,
GLint *slices*,
GLint *loops*,
GLdouble *start*,
GLdouble *sweep* )

## PARAMETERS

*quad* Specifies a quadrics object (created with
**gluNewQuadric**).
*inner* Specifies the inner radius of the partial disk (can
be 0).
*outer* Specifies the outer radius of the partial disk.
*slices* Specifies the number of subdivisions around the *z*
axis.
*loops* Specifies the number of concentric rings about the
origin into which the partial disk is subdivided.
*start* Specifies the starting angle, in degrees, of the
disk portion.
*sweep* Specifies the sweep angle, in degrees, of the disk
portion.

## DESCRIPTION

**gluPartialDisk** 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 *start* through *start* + *sweep* is
included (where 0 degrees is along the +*y* axis, 90 degrees
along the +*x* axis, 180 degrees along the *-y* axis, and 270
degrees along the *-x* axis).
The partial disk has a radius of *outer*, and contains a con-
centric circular hole with a radius of *inner*. If *inner* is 0,
then no hole is generated. The partial disk is subdivided
around the *z* axis into slices (like pizza slices), and also
about the *z* axis into rings (as specified by *slices* and
*loops*, respectively).
With respect to orientation, the +*z* side of the partial disk
is considered to be outside (see **gluQuadricOrientation**).
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GLUPARTIALDISK(3G) UNIX Programmer's Manual GLUPARTIALDISK(3G)
This means that if the orientation is set to **GLU_OUTSIDE**,
then any normals generated point along the +*z* axis. Other-
wise, they point along the *-z* axis.
If texturing is turned on (with **gluQuadricTexture**), texture
coordinates are generated linearly such that where
r = outer, the value at (*r*, 0, 0) is (1.0, 0.5), at (0, *r*,
0) it is (0.5, 1.0), at (-*r*, 0, 0) it is (0.0, 0.5), and at
(0, *-r*, 0) it is (0.5, 0.0).

## SEE ALSO

**gluCylinder(3G)**, **gluDisk(3G)**, **gluNewQuadric(3G)**,
**gluQuadricOrientation(3G)**, **gluQuadricTexture(3G)**,
**gluSphere(3G)**
MirBSD #10-current Printed 2021-12-07 2