What is Inverse Kinematics, and why do we need it?
The word “kinematics” is defined as the mechanics behind the motion of an object but without referencing the forces that cause this motion. So, every part of our daily motion can be described, in kinematic terms, as the movement of our bones.
The two types of Kinematics
If we look at the character animations in Chapters 10–12, the kinematics definition also holds true. The type of animation of our character is called Forward Kinematics. An example of Forward Kinematics is shown in Figure 13.1:
Figure 13.1: Raising the hand of the simple skeleton by using Forward Kinematics
The skeleton in Figure 13.1 raises its simplified hand by rotating the arm at the shoulder (1), and the elbow (2).
During the movement or rotation of the skeletal bone, all the other nodes attached to it are also affected. Rotating the arm around the shoulder does not change the elbow or the forearm, as...
