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

Chapter 20 - QuickDraw 3D Mathematical Utilities / QuickDraw 3D Mathematical Utilities Reference

QuickDraw 3D Mathematical Utilities / Setting Up Transformation Matrices

Q3Matrix3x3_SetRotateAboutPoint

You can use the Q3Matrix3x3_SetRotateAboutPoint function to configure a 3-by-3 rotation transformation matrix.

TQ3Matrix3x3 *Q3Matrix3x3_SetRotateAboutPoint (
TQ3Matrix3x3 *matrix3x3, 
const TQ3Point2D *origin, 
float angle);

matrix3x3

A 3-by-3 matrix.

origin

The desired origin of rotation.

angle

The desired angle of rotation, in radians.

DESCRIPTION

The Q3Matrix3x3_SetRotateAboutPoint function returns, as its function result and in the matrix3x3 parameter, a rotation matrix that rotates an object by the angle angle around the point origin.