What is easing? Easing is something that will help you get more natural movements.

When you move your hand, does it go from stationary to moving to stationary again?

No, it slowly picks up speed and then slowly looses speed [depending on the motion].

So how do we ease in and out in out animations?

Many of you aren't going to like the answer, but here it is... You add more frames to it.

Let me show you.

I'm going to make a pendulum swing back and forth. Not real difficult... First draw the extremes:

Then we draw the middle position. And a quick note on that... We have to maintain the images form and the arch of movement. So we can't draw the middle point like so:

We have to draw it like this, because the line that the pendulum swings on doesn't deform and change size.

Compare the animations:

This is all standard fare, what we covered in the last tutorial, keyframes and in betweens, but now we are going to make the swing more realistic by slowing it down on the ends. How do we do that? Add frames...

But we can't just place them at the inbetween points. Well, we can but it will slow down the animation as a whole, not just when the pendulum swings to the far left or right.

By placing them there, we slowed the action down on the sides but the swing will still happen quickly. Because there are more frames on the swing back it will take slightly longer... As in the animation below:

Let's add one more frame in there to slow it down more:

This is set at the same speed as the image above, notice the slow down?

This is where I added the inbetweens.

We can apply this to the human body to make it appear more lifelike. I'm going to use our sprite from last time and make him throw a ball. Now, there is a LOT more to making this sprite look lifelike than what I'm going to do. But that would be for another tutorial. I'm just going to move his arm not the rest of his body, like would normally happen when throwing a ball.

So there he is again, and I still have him on seperate layers:

This way animating the arm won't physically cover up parts of his body, forcing me to have to redraw parts of his body each time the arm moves.

I'm going to give myself a little more room first:

That's nice. Now for animation.

And again, stick to what we know, draw the extremes.

Those are just the extremes for him lifting his arm, there will be more later. But for now, let's do the middle position and the inbetweens.

There we go. Test the animation and see how it looks.

Just fine. So now we are going to add the easing. He is going to hesitate before throwing the ball and then toss it. To make him hesitate, we add cushioning frames after his arm has been lifted. Like so:

I added 3 extra frames which makes the animation look like this:

I changed the image of his hand so that it looks like he's holding a ball or something. Now I'm going to flesh out the stick arms with his real arms...

Here's the animation without the easing:

And here it is with the easing.

Something you have to do it realize how the body moves. The elbow leads the action. It pulls the forearm and hand behind it so that when the elbow gets to the top position, it moves very little and the forearm and hand move more, setting into place. It all comes down to your observational skills.

Now, this wasn't hard to draw at all because it's all just straight lines for the arm and a little hook for the hand, and it looks just fine.

Next we have to draw him throwing the ball, so we're going to use the last frame in the animation we just did as the first extreme, then I'm going to draw 2 more extremes. One of them being him just when the ball was about to leave his hand, and the next with his hand down having already thrown in.

Blue arm is when the ball is leaving his hand, green line is for the follow through.

Throwing the ball means that he has to speed his arm up pretty fast and then it slows down on the follow through... So I might not have to draw another frame for the throw other than the blue line... The start of the throw will use one more frame behind the extreme, and the follow through will use maybe 3 more frames for the ease out.

This should produce a nice fluid movement. Let's do the drawings then...

The reason I am putting a frame in before the first extreme is to anticipate the throw. Think about cartoons [or stop reading this and watch one! Everyone loves cartoons.] when a door slams shut, it more than likely will open up a little bit first, maybe one frame and then slam shut. It helps to give a little bit more power to the slam. Again, this isn't the best example of it but it's all I have to show you.

That's what I have, I hope it looks good cause I'm just going to go right into fleshing out the arm.

You could even add a motion blur in between and just have the ball fly out of it, if you wanted that is. I'll try both.

First, without the blur:

I got rid of that last frame and third to last frames from the stick sketch I have above. I tend to over draw sometimes and this was a time that it happened. The animation went too slow so out they went.

Another thing to remember, this tutorial is only handling his arm movement. There are many many things you could do to this figure to make him appear more lifelike that I'm not going to cover in this tutorial. Aching his back and sticking his other arm out as a counter-balance would do wonders. Having him take a step back with one foot to support himself and then throw his whole body into it would also be quite nice. But I'll save that for another time.

At the moment I'm going to throw a motion blur in there and see how it looks. Probably not that good...

Eh, it doesn't look that bad, but it doesn't really add to the animation. The original way I had it I think is best because his body doesn't move at all so his arm wouldn't move the speed that a motion blur would suggest. But it's personal preference, and a motion blur is harder to draw than a normal arm. So that's my try at teaching you easing. I hope it helped at least a little bit.