Animating human like characters is much more complex than an animating other objects.
Humans generally do much more complex things than tables or
chairs and we're much more attuned to human movement than to that of other things.
We will notice very small areas in human movement
which we just wouldn't notice in the movement of the car.
We generally divide character animation into movement of
the body and movement of the face and use different techniques for each.
Body movement is all about movement of
the skeleton and bones are hard so they don't change shape much.
Instead, most of the movement comes when we rotate tied joints like the elbow.
This means that the skeleton is the key thing that we animate.
The face, on the other hand,
only rarely has one movable joint, the jaw.
But there are still very important movements and social signals in
our facial expressions that come from small movements of the muscles of the face.
The eyes are probably the most important part of the face when it comes to
social interaction and they use different techniques again.
Like bones, it is very much about how they were tied to look at things.
There are two basic ways to animate characters for VR: using
prerecorded animations or generating movement using procedural simulation.
A prerecorded animation is a sequence of poses
of the character that can be played by it to create movement.
They can be hand animated using keyframe animation or
recorded from a real person using motion capture.
This kind of animation is not that flexible.
You can only play back what was
recorded and it can't be adapted to what you need in the moment.
But you can use different techniques to select
an appropriate animation clip in response to what is happening.
Unity uses a method called state machines.
The benefit of prerecorded animation is that you can
achieve complex and realistic movements so,
it's well suited to sophisticated full body or facial movement.
Procedural animation is about generating movement in real-time from code.
A script controls how the character moves in response to what's happening.
It's much harder to create complex realistic animation using procedural animation,
but since the animation is generated from scratch as the program runs,
it's much easier to respond very exactly to what the players doing.
It's good for things like eye animation where the movement itself is quite simple,
just rotating the eyes in their sockets but,
you want the eyes to point in exactly the right direction.
In the next couple of weeks,
you'll learn a lot more about animating characters.
Both how to animate and what to animate.
And very soon, you'll be creating realistic VR characters.