# gluPartialDisk.3G - Man Page

draw an arc of a disk

## C Specification

```	GLdouble inner,
GLdouble outer,
GLint slices,
GLint loops,
GLdouble start,
GLdouble sweep )```

## Parameters

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 $z\text{ }=\text{ }0$ 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 $r\text{ }=\text{ }\text{outer}$, 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).