GLUPARTIALDISK(3G) UNIX Programmer's Manual GLUPARTIALDISK(3G)
NAME
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 +y 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 con-
centric 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).
MirBSD #10-current Printed 2021-12-07 1
GLUPARTIALDISK(3G) UNIX Programmer's Manual GLUPARTIALDISK(3G)
This means that if the orientation is set to GLU_OUTSIDE,
then any normals generated point along the +z axis. Other-
wise, 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(3G), gluDisk(3G), gluNewQuadric(3G),
gluQuadricOrientation(3G), gluQuadricTexture(3G),
gluSphere(3G)
MirBSD #10-current Printed 2021-12-07 2