All language subtitles for 03-05-Polishing the bouncing ball

- [Instructor] Let's
polish our bouncing ball.

The first thing I will do

is select all the key, press T

and switch to Bezier.

Now we have interpolation
between our keyframes

and the first thing we can see

that we get some slowing down

or easing before the
ball touch the ground.

You can switch to the graph editor

through the header or
pressing Control + tab

when you are in the action editor.

I have activated the display selected only

and I will start polishing
the route of my ball.

When looking at the curve,

I can see that only the z and y curves

are currently animated.

All the rotation, scaling and
x location curve are flat.

To make my editing easier,

I will expand the root panel

and I will just hide all the curves

that I'm not using,

only keeping the z and y location curve.

Remember what we have seen
in the previous chapter.

When an object is falling,

it is at its maximum speed

just before hitting the ground,

so I can select my z contacting keyframe,

press V and switch it to three

and then rotate the left handle

to get a proper curve.

It already feels way better.

But I'm a bit disturbed by
the y motion of the ball.

The frame just before
it contact the ground

looks a bit weird.

And this is because we
have easing on our y curve.

The y curve has an S shape

between the IS point

and it's contacting pull.

But as seen in the previous chapter,

when a ball is falling,

it is accelerating until
it touch the ground

but its motion forward is pretty constant

because even if there is air friction

that will slow down the ball,

on such a motion, it's barely noticeable.

So I can switch both
handles to free our vector

and align them to get a
more linear interpolation.

So as a first polishing
path or splining path,

I will simply repeat this
process on each bounce.

To get a clean viewport,

I'm activating and
deactivating the overlay

with a shortcut I've set previously.

So I will break all the z-axis handle

by switching them to vector

on the contacting frame.

I will remove the intermediate
frame on the y-axis

because it's useless

since we will create
a linear interpolation

between the contacting and air pose,

switching our handles to vector.

I will use this method each
time the ball is airborne

but on the final stage of the animation,

I will keep the easing toward
the very last keyframe.

So as you remember in
the previous chapter,

I like to keep the ball a bit
longer in the air generally

just for style sake.

So on the z curve,

I will take each key where
the ball is in the air

and I will slightly scale the handles.

This way, the ball will rise
a little faster in the air

and it will be kind of thwarting a bit.

Please consider that animation
is not a linear workflow.

And I will remove some keyframe,

remove them, retime some
part of the animation

and tweak it a lot.

So it's a lot of back and forth

before you achieve a decent result.

And you can tweak an animation forever

but there is a moment
where you have to stop.

Before the second bounce,

I feel like there is a slight
glitch in the animation

because the ball is staying
too long on the ground.

So I will shorten this hold
on the ground by one key,

offsetting all the keys
after key number 20.

As it does improve the animation,

I will do the same
between frame 25 and 26.

There is a hold on the ground

but I feel it's too much.

So I will get rid of frame 26

by offsetting it onto frame 25

so that on the very last bounce,

the ball is staying on the
ground only for one frame

instead of two.

If we now have a closer
look to our y curve,

we can see that we have
a pretty logical pattern.

Each time the ball touch the ground,

the y curve get flatter and flatter,

meaning that the ball is losing speed

on each impact but when airborne,

it has a linear movement.

And as soon as it stays on the ground,

we will have a slight easing

from frame 29 to frame 43

when the ball is slowing down.

Watching the animation again and again,

I feel like there are still some glitches

and some bugs I have to fix

and when having a closer
look at my z curve,

I can see that I have some easing

after the impact, which is not correct.

So I will fix this.

After those modification,

my animation should look better

but I still have some glitches.

And this is because all the
transformation we have done

with the squash and stretch

haven't been polished

and haven't be retimed.

I've made a few modification

on the timing of the route of my ball,

so now the other animation
that were in sync

during the blocking stage

are no longer in sync.

So I will deactivate all
the other transform channel

just to see my root motion.

And now I can see that
it feels way better.

So there is still this moment

where the ball stops on the ground

but this is because we will have motion

through the squash and stretch.

So without the squash and stretch,

it looks a bit weird

but as I renabled it and
as I will be polishing it,

I will be able to fix the problem here.

If you want your animation
to look a bit more realistic,

just remove those holding frame

and just make the contacting
pose on one frame.

Then reduce a bit the squash and stretch.

This is just a matter
of personal preferences.

I like it a bit stylized,

so I'll keep those holding poses.

I will now work on the upper
squash and stretch controller.

This one is going to be
pretty easy to polish.

I select the first keyframe

and press on the dot key on
the num pad to frame them.

I'm mainly watching the
orientation of the ball created

by the stretching effect.

You can also calculate the
motion path of this ball

if this does help.

Here what I want is to give
back a bit of verticality

to the ball.

So I will slightly offset the beginning

of the stretching on the y-axis.

I will hide the z curve
by clicking the I icon

and then select the first keyframe,

press Shift + D to duplicate it

and move the duplicated
key on frame three.

As it looks a bit too delayed,

I will move back this
key on frame number two

and then I will switch
the handle type to three

so that I can shape a bit the curve.

This way, I have a better feeling

that the ball is currently aiming

or pointing toward its landing spot.

Then I will work on the z curve

that currently squash and
stretch the ball the most.

And I will just switch
the impact point to vector

because this is an impact frame

where the ball switch from
squashing to stretching again.

Then I will go onto the next jump.

I will reselect my root bone

and I will recalculate the motion path

because it does help me figuring

where the ball is supposed to land

and also where the top of the ball

is supposed to be pointing at

and this is why here,

I will slightly push the
top to the ball forward

toward the previous keyframe position

by pushing my z curve a
bit up in the graph editor.

I scrub a bit onto my animation

to see how it does move.

Then I will select the z-axis curve,

switch it to vector on this middle frame

and then move forward
toward the next jump.

First, I feel like it's offset in time.

So I will select all the curves

and move them by one keyframe
prior to the current one.

The ball is currently
leaning too much backward

on on these three

and I can figure this by
watching the F curve value.

When selecting the keyframe,

I can see that its value is set to -65

and if I select the
previous one, it has -56.

It means that this last
keyframe is further away

from its value zero

so it means the controller is offset more

and so it's more deforming the ball

than the previous bounce,

which doesn't make sense since this bounce

is less powerful,

losing energy compared
to the previous bounce.

So I will push this keyframe

towards zero in the graph editor.

For the very last bounce of the ball,

I don't want any deformation.

So I will just get rid
of the next keyframes.

From there, we can watch
our animation several time

and jump into polishing the
next squashing controller.

I will select the lower green controller

and since the curve are pretty small,

I will use the normalize option

to be able to see my green channel.

Since we have used the
upper green controller

to give an orientation to
the bounces of the ball,

I don't need to do the same

with the lower controller.

So I will just make my y curve flat

by removing the keys that are offset

because they won't bring
anything good to our animation

and they are currently almost useless

as their value is very small.

So just get rid of them.

Now regarding the z-axis

that will allow us to
squash the ball in the air

when it's reaching its highest point,

I want it to be very subtle.

So I will offset the
starting and ending keyframe

of those motion by two frames.

And I will repeat this process
along the whole animation.

I will shorten the length of this motion

and as I go forward,

I will reduce the amplitude of the curve

because again, with energy loss,

I will get the less squash
and stretch on this motion.

This controller allow us to
add very subtle deformation

to the ball, so it's interesting

to make it as good as possible.

When I'm done with it,

we can clearly see the energy loss

during the motion of the ball.

I will fix the timing of the last squash

because it doesn't
occur at the right time.

It's supposed to happen

when the ball is at its highest point.

And then again I can watch
my animation several time

to see if it looks okay.

So that's great.

We have a bouncing ball
but it's not rolling.

This is because we haven't
animated the rotation controller

of the ball yet.

In this case, it wouldn't make sense

to block the spinning of the ball.

Since it doesn't change its shape,

we wouldn't be able to see any change

during the blocking stage.

So I will select all the keyframes

but the first one and get rid of them.

Just press X and confirm.

Then select the first keyframe

and move it on frame eight.

This is the frame where the ball

is contacting the ground.

So I get a flat curve

from frame zero to frame eight.

It means that the ball won't be rolling

while it's in the air.

I want it to start spinning

when it will touch the ground

and when part of the energy of the impact

will be transferred to its rotation.

I will duplicate again the keyframe

and move it to move frame 18.

This is where I want the
ball to be spinning already.

Nothing happens because I have disabled

the transform channel.

I need to reenable it.

Now when I move the curve,

the ball should be rotating

but it's barely noticeable

and this is because I need

to unzoom in my graph editor.

Since the value of the
rotation is in degree,

I need to drastically modify the curve

and move it onto way
higher or lower values

in this case.

Pushing the value down to -360 degree

will make the roll spin forward.

So that's fine.

On the impact, the ball will
get full rotation speed,

so I will switch this to vector.

Due to the frequency of the rotation

and the animation, I have
a hard time figuring out

if the ball is currently rotating or not

because the ball pattern
seems to get aligned

on each frame so it's a bit weird.

So I will get rid of the overlay

to have a better vision of it.

I will also switch the second handle

to vector two because
the rotation of the ball

is not supposed to slow in the air

and since I still have some difficulties

to read the rotation,

I will enable all the
other controller keyframe

and disable their
influence on the animation

so that I can clearly see

if my ball is rotating or not.

The initial air rotation speed

of our bouncing ball
is not that important.

What will be important

is the final rotation speed

because it will have to match the speed

of the ball traveling on the ground.

So what we need to do is to
duplicate the current keyframe

and move it on the next contact post.

And we need to make the ball
spinning a little less faster

than the previous pose

because it's losing energy on each bounce,

so it's also losing rotation speed.

Then we will create a
last keyframe on frame 43.

It's the frame where the bouncing ball

is currently stopping in space.

And this time we will
switch it's handle type

to Bezier because we need
some easing in the end.

We don't need a linear interpolation.

The ball is slowing down

so its rotation is also slowing down.

To make this stage
readable, I need the grid

because I will need a
point of reference in space

to see if the pattern of the ball

is still aligned with
it whenever it's rolling

on the ground.

So I will re-enable the overlay

and I will zoom a lot onto my animation.

Now I will try to find the point

of reference using the pattern of the ball

and the grid.

When I find it, I will
Shift and right click on it

to place the 3D cursor.

Now what I want is to make sure

that the pattern of the ball

is pointing toward the 3D
cursor as the ball stop.

To do so, just zoom a lot

and then fine tweak the
position of your last keyframe.

You will also need to
slightly tweak the rotation

or orientation and
scale of the last handle

to make sure that we don't
have this sliding effect

on the ground.

Just do it by little touch.

If you see that your
animation is completely off,

it means that your whole
curve is completely off

and the difference between your final key

and the previous key,
the key from frame 30

is way too big.

Rotation easing when
you have a contact pose

is pretty hard to get
right on the first shot,

so be patient, tweak your curve

until you get this nice
rotation on the ground

and the feeling that the ball
is really rolling onto it.

And if you can't achieve
this, don't panic.

Open a new Blender file

and just make the ball
rolling and stopping.

Work on the curve until you
get this animation right

and you will understand the relationship

between your rotation curve
and your translation curve.

It's not a question of math
or geometry or whatever.

It's just a question of practice.

It might be a bit complicated at first

but with a bit of training,

you will get comfortable

with this kind of motion pretty soon.

And if you really want
to get good at animation,

it's very important

because you will use
animation curves every day.

So from there, I can
call this animation done

but there were a few glitches

that I wanted to fix.

Those are little things,

so I won't be going in details into it.

I've just added a very small
additional bounce at the end

and I've a bit revised the
z amplitude of my route

so that the ball get a more even bouncing.

So there is not much you will learn

from the next step.

I'm just refining some of the poses.

I'm doing what we've
been doing just before,

slightly revising the timing,

the amplitude of the curve, et cetera.

What you need to understand

is that again, an animation

is never finished until you say stop.

And just work your animation

until you get to a point of satisfaction.

If you're struggling with the animation,

start a new one.

And this is the only
way you will progress.

I've said this before

and I will say it a lot of
time during this course,

you need to animate to
become a good animator.

You need to make this bouncing
ball exercise multiple time

until you will get a good result.

This is how it works.

I am still struggling

to get a good bouncing ball result

after several years of animation.

And to bring a character to life,

to animate a character,

you need to first be able

to give it motion and then
you will input personality,

input emotion but before
you input emotion,

even into a bouncing ball,

you need to learn motion.

All right, enough of
philosophical discussion.

Let's go ahead with the next video.