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/.