# GLUPARTIALDISK

Section: Misc. Reference Manual Pages (3G)

Page Index

## 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* )

delim $$

## 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 concentric 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**).
This means that if the
orientation is set to **GLU_OUTSIDE**, then any normals generated
point along the +*z* axis. Otherwise, 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)**