gluPartialDisk function

Article
12/11/2020

The gluPartialDisk function draws an arc of a disk.

Syntax

void WINAPI gluPartialDisk(
   GLUquadric *qobj,
   GLdouble   innerRadius,
   GLdouble   outerRadius,
   GLint      slices,
   GLint      loops,
   GLdouble   startAngle,
   GLdouble   sweepAngle
);

Parameters

qobj: A quadric object (created with gluNewQuadric).
innerRadius: The inner radius of the partial disk (can be zero).
outerRadius: The outer radius of the partial disk.
slices: The number of subdivisions around the z-axis.
loops: The number of concentric rings about the origin into which the partial disk is subdivided.
startAngle: The starting angle, in degrees, of the disk portion.
sweepAngle: The sweep angle, in degrees, of the disk portion.

Return value

This function does not return a value.

Remarks

The gluPartialDisk function 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 positive y-axis, 90 degrees is along the positive x-axis, 180 degrees is along the negative y-axis, and 270 degrees is along the negative 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 positive 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 positive z-axis.

If you have turned on texturing (with gluQuadricTexture), gluPartialDisk generates texture coordinates 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).

Requirements

Requirement	Value
Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Header	Glu.h
Library	Glu32.lib
DLL	Glu32.dll