OpenGL man pages
gluPartialDisk - draw an arc of a disk
void gluPartialDisk( GLUquadricObj *qobj,
GLdouble sweepAngle )
qobj Specifies a quadrics object (created with gluNewQuadric).
innerRadius Specifies the inner radius of the partial disk (can be zero).
outerRadius Specifies the outer radius of the partial disk.
slices Specfies 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.
startAngle Specifies the starting angle, in degrees, of the disk portion.
sweepAngle Specifies the sweep angle, in degrees, of the disk portion.
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
startAngle through startAngle + sweepAngle is included (where 0 degrees is
along the +y axis, 90 degrees along the +x axis, 180 along the -y axis, and
270 along the -x axis).
The partial disk has a radius of outerRadius, and contains a concentric
circular hole with a radius of innerRadius. If innerRadius is zero, 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=outerRadius, the value at (r, 0, 0) is
(1, 0.5), at (0, r, 0) it is (0.5, 1), at (-r, 0, 0) it is (0, 0.5), and at
(0, -r, 0) it is (0.5, 0).
gluCylinder, gluDisk, gluNewQuadric, gluQuadricOrientation,
Fri Dec 6 11:18:03 EST 1996
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