What exactly is inverse kinematics? A short search tells me it is something like "if the hand goes in a certain position and a certain angle, elbow and shoulder must go into these angles", is that it?
Imagine placing the feet on the ground at some location and then pinning them there. Now you can move the hips and the upper and lower legs as well as the knee orientations change to keep the feet planted in the same position.
This image explains it pretty well, you typically chose between Forward Kinematics, or Inverse Kinematics, depending on what you're trying to accomplish and how you want it to look like: https://www.researchgate.net/profile/Ebrahim-Poustinchi/publ... (imagine the robot parts are human limbs, same thing applies :) )
Does it just make it easier to get in a position you want or does it give you more natural looking positions as well or any other benefits? It's pretty fun to play with!
It means that you can lock the end point to a position and figure out the rest of the pose.
Imagine a character walking with forward kinematics. Every time you move the characters hips , you’d have to rotate the leg joints and make sure the foot doesn’t slide. Remember virtual characters don’t have friction.
IK lets you lock the foot in a spot so you can animate the body above it without having to spend time matching the foot position.
In a real world, this is like if you tried to put your hand on a door handle while jumping up and down. It’s easier to keep position when you hold the handle than if you were to just touch it.
It also means you can move the point and the rest of the joints adjust. Want to make your model walk? Just figure out the foot motion and the rest of the details are calculated based on joint range of motion and limb length.
