# gluPartialDisk.3G - Man Page

draw an arc of a disk

## C Specification

void **gluPartialDisk**( GLUquadric* *quad*,

GLdoubleinner, GLdoubleouter, GLintslices, GLintloops, GLdoublestart, GLdoublesweep)

## 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 $z\text{\hspace{0.5em}}=\text{\hspace{0.5em}}0$ 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 +*yaxis, 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 $r\text{\hspace{0.5em}}=\text{\hspace{0.5em}}\text{outer}$, 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)

## Referenced By

gluCylinder.3G(3), gluDisk.3G(3), gluNewQuadric.3G(3), gluSphere.3G(3).