gluPartialDisk

Nom

gluPartialDisk -- draw an arc of a disk

Prototype

void gluPartialDisk (GLUquadric* quad,
                     GLdouble inner,
                     GLdouble outer,
                     GLint slices,
                     GLint loops,
                     GLdouble start,
                     GLdouble sweep );

Paramètres

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 concentric cir- cular hole with a radius of inner. If inner is 0, then no hole is gen- erated. 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 consid- ered 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).

Voir aussi

gluCylinder, gluDisk, gluNewQuadric, gluQuadricOrientation, gluQuadricTexture, gluSphere.