In this one lesson we're gonna cover two  principles of animation. And that's because they can sometimes get confused together  and they are overlapping action and secondary action. They're two totally different things,  but we're gonna start with overlapping action  so we can be able to tell the difference  between the two principles of animation. So as the Disney animators began animating  and discovering these principles,  this one stood out When they found that when they're,  they were animating their characters  and they animated them coming to a stop, they found  that it felt too rigid and unnatural. And they used this principle  to create more natural movement. And so this principle basically says that  not everything stops at the same time.

So when we're walking and we come to a stop  or something, not all pieces of our body stop  or even start when we start walking at the exact same time. And so there's overlapping action. That's where the name overlap comes in,  because different pieces of the body  or subject overlap with the other. So some may come to a rest before the others  or some may start moving before the others. And so taking advantage of this principle means  that you can create a lot more natural and fluid movement. And if we want to get into the science of why that is, it's  because of something called kinetic energy.

And that basically means by the virtue of something moving,  it has built up energy  and it takes time for that to settle to a stop  or even start to create that energy. And so because of a different object's mass or friction  or all these other variables, they can start and stop  or take longer time to to start and stop. So let's take a look at a couple of examples. Let's begin with this jump and spin. Because the athlete spun  and lands on one foot doesn't mean the motion stops when  his foot hits the ground. His body still has the force  of the spin in that kinetic energy.

And the ray light continues to spin as an example of follow  through from the energy of the original spin motion. When he does stop, we can also observe another animation  term related to this principle of overlapping action. The term is overshoot,  which means the object goes past its final rest  pose and then comes back. It overshoots it. So because his body has weight, we can see he goes down  or overshoots his final rest pose before he extends his legs  and up into a more neutral rest pose. But we can still see  that despite his waist stopping from moving,  that his arms continue to move.

As another example of overlapping action,  this can apply not just to people's bodies, but also clothes  and accessories like earrings that swing long  after the person has stopped moving. And at an animation conference,  I once heard the famous Disney animator, Eric Goldberg,  refer to this principle as adding flux  to an animation. He was doing a demonstration about  how a jumping character's dress would drag  behind the character. And then at the peak of the jump it would catch up  and kind of add this, what he would describe as flounce. I'd never heard that term before. So you're always learning in animation  and everyone sometimes can have their own way  of describing the same motion.

And in motion graphics, it can be used  to create an authentic and fun feel to the motion. Like these examples where the cloth drags behind the ball,  it's draped over and the overlapping of the springs wobbling  after the ball passes through them. And let me just remind you that these principles aren't some  old dusty throwback thing that is never used these days. I actually used it when I animated on Disney's 2019  remake of Aladdin. So I was hired late in the production,  and so I was helping them final some shots. And some of those shots included the monkey character in the  film Abu.

And in some of these shots, most of them, he came to a stop. He would scurry along  and then kind of come up next to Aladdin  or come into his rest pose for that scene. And he has a tail and his tail is quite springy. And that was part of my job, was to add overlapping action  of his tail for when he comes to a stop so  that it looked realistic to that monkey character. And in that case it was photorealistic. So I needed to take  that into account when I was using reference  to figure out what's the weight  of this tail based on the size of this monkey,  how fast he was moving, and the appeal  and keeping the shape that nice curled look of the tail.

So that's something to keep in mind  that these things I use every day. Um, and so let's get into the the second  animation principle for this lesson. Secondary action. And that can sometimes get confused  with this first principle. We talked about overlapping action  because they both have action in their name  and they also kind of happen secondary to the main motion. But in the case of overlapping action, we've learned  that's due to the kinetic motion, the kinetic energy  that needs to be settled or started and how that is offset  or overlaps with the main action.

And different pieces of the body move  and stop at different times because of kinetic motion. Now, secondary action has to do with  the actual performance choices  and helping to convey the emotional state of the character. And what I mean by that is take  for example an an someone who's angry  and they're gonna stand up angrily from a desk or a a chair. And the main motion is them standing up, right? But how can we add a little more, um, believability into  that performance to show his emotional state? We might shake his head  as he stands up like a quick little shake.

The secondary action is his head shake. The main motion is his body moving. He may have overlapping action  and other principles may be at play as well. But secondary action is specifically about adding  texture to your animation. And what that means is adding that extra charming quality  and specific acting choices for a character performance. So it has less application  to something like motion graphics.

And it's very much specific about a character  performance animation. Sometimes these choices come later as the shot progresses  and animators realize they need to find a way  to plus the shot. And that's another term you might hear quite often is trying  to figure out a way to plus your work. Or you might be working at a studio  and get someone else's work. Maybe they left the project  and it's now your job to plus their work. So you have to start to think about  and find interesting ways  and interesting choices that's authentic to the character  and the performance in a way that supports the main action.

The secondary action is never meant to be  overtaking the main performance. If it does, then it's no longer a secondary action. It should always be subordinate and support the main action. So an example of  that from my career has been working on the movie. Welcome to Marvin. I was an animator on that show  and the actor Steve Carell was opening a door  for his love interest.

And that movie was shot with motion capture,  which which means the characters were on a stage  with suits on and their motions were recorded  and they were given to us as animators to apply to the CG  or the computer generated characters. So in this one performance,  he opened the door for his love of interest. His love of interest walked past him and inside the door. And that's the end of the scene. And the motion capture data got that fairly well. There's other details to that that were too technical  to discuss here that I had to deal with.

But in general, that performance worked great. But part of my job as an animator is to find ways  to plus these things when appropriate. And one of the things I put forward as an idea  to my animation director was for Steve Carell to  not just open the door, but as she passes,  and for him to take his hat off  and put it on to on his chest, kind of lovingly  and longingly as she walks past him. Now, the main motion was him opening the door. And my idea for secondary action was trying to convey  that she's his love interest  and what's something that I could do  that didn't involve him talking just a very simple gesture  that supported the main motion of him opening the door. And it also communicated his feelings towards her.

So keep in mind these principles are not, you know,  in only in textbooks. I use these every day in my work. So in this lesson, we learned overlapping action, also known  as follow through is about the overlapping action  of motions that can arise from kinetic energy  of objects needing to come to a rest or beginning to move. Then we learned about  how secondary action is also another animation principle  and separate from overlapping action,  even though they sound a little bit similar. And secondary action is about supporting the character  performance with smaller choices that help support  and are subordinate to the main action. So in the next lesson, we are going  to actually have an assignment  where we animate a fish eating another fish.

And we're gonna use both  of these animation principles at the same time,  on the same animation so that you can tell the difference  between them even more. So I'll see you there. Thanks for watching.