1991-2006
Silicon Graphics, Inc.
gluPartialDisk
3G

# 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 +\f2y\f 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, gluDisk, gluNewQuadric, gluQuadricOrientation, gluQuadricTexture, gluSphere

## Copyright

Copyright 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.