Game Development Reference
In-Depth Information
Angular Velocity and Angular Acceleration
An object can also have a velocity and acceleration in terms of its angular movement. The distance
an object rotates about its rotation axis is measured in radians or degrees. In Figure
5-10
, you see
an object that is rotating about its rotation axis. The initial starting point is the angle theta1, and the
ending angle is theta2. The change, or delta angle amount, is theta2 - theta1.
y
∆θ
θ
2
θ
1
x
Rotation Axis
Figure 5-10.
Rotating an object
The average angular velocity is the change in the angular position, divided by the change in time.
The instantaneous angular velocity is the first derivative of the angular position with respect to time.
(See Figure
5-11
.)
Figure 5-11.
Angular velocity
The average angular acceleration is the change in the angular velocity, divided by the change in time.
The instantaneous angular acceleration is the first derivative of the angular velocity. (See Figure
5-12
.)
Figure 5-12.
Angular acceleration
