HP Workstation zx2000 OpenGL 1.1 Reference for HP-UX 11.x - Page 318

gluPartialDisk

Page 318 highlights

P gluPartialDisk gluPartialDisk 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 inner outer slices loops start sweep Specifies a quadrics object (created with gluNewQuadric). Specifies the inner radius of the partial disk (can be 0). Specifies the outer radius of the partial disk. Specifies the number of subdivisions around the Z axis. Specifies the number of concentric rings about the origin into which the partial disk is subdivided. Specifies the starting angle, in degrees, of the disk portion. 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 along the Y axis, and 270 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). 318 Chapter 14

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P
gluPartialDisk
Chapter 14
318
gluPartialDisk
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 along the Y axis,
and 270 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).