Inside Macintosh: 3D Graphics Programming With QuickDraw 3D /

Chapter 7 - Transform Objects / Transform Objects Reference

Data Structures

Rotate-About-Axis Data Structure

You can use an rotate-about-axis transform data structure to specify a rotate transform about an arbitrary axis in space at an arbitrary point in space. The rotate-about-axis transform data structure is defined by the TQ3RotateAboutAxisTransformData data type.

typedef struct TQ3RotateAboutAxisTransformData {
   TQ3Point3D                 origin;
   TQ3Vector3D                orientation;
   float                      radians;
} TQ3RotateAboutAxisTransformData;

Field Description

origin

The origin of the axis of rotation.

orientation

The orientation of the axis of rotation. This vector must be normalized or the results will be unpredictable.

radians

The number of radians to rotate around the axis of rotation.