quat_slerp man page

quat_slerp — Version of quat_interpolate() allowing control over the rotation. Allegro game programming library.

Synopsis

#include <allegro.h>

void quat_slerp(const QUAT *from, const QUAT *to, float t, QUAT *out, int how);

Description

The same as quat_interpolate(), but allows more control over how the rotation is done. The how parameter can be any one of the values:

QUAT_SHORT  - like quat_interpolate(), use shortest path
QUAT_LONG   - rotation will be greater than 180 degrees
QUAT_CW     - rotate clockwise when viewed from above
QUAT_CCW    - rotate counterclockwise when viewed from above
QUAT_USER   - the quaternions are interpolated exactly as
              given

Info

version 4.4.2 Allegro Allegro manual