Original subtitles

- Once the bag rotation master controller

and the root were done,

I've locked their transformed channels

so that I was sure I would not edit them by mistake.

From there, I will select all the other controller

and get rid of all the keys but the very first one.

Since the bag deformations are very fast,

it's easier for me to rework them from scratch

then trying to work from

what we have blocked before.

Whenever I want to create a pose, I will make sure that

the previous key frame is currently keyed.

This way, I'm sure to avoid any undesired interpolations,

On frame 12, I will kind of sculpt the bag

as it receive the first jab

by pushing the tweaker controller.

And then a couple of frames later,

I will just console all the transforms

so that the bag recovers its shape.

Then a frame later, I will pull a bit

the controller that was hit by the punch

so that we get a very subtle shake feeling.

Then I will repeat the process for the next punch.

I will key the controller on frame 16,

the frame prior to the hit or impact.

Then on frame 17, I will sculpt the bag

by pushing the tweaker bone,

but also scaling them on one axis

and then scaling them down on the opposite taxis.

I'm trying to preserve the volume of the bag.

From there, four frames later,

I will console all the transform, and then

I will refine the shape of the bag frame-by-frame.

Since the the hitting frames are pretty short,

it's a very fast process.

Rebuilding the whole animation for the whole bag

took me about half an hour.

Then, I started over again with the hook,

Sculpting the pose from scratch using the tweaker bones.

As soon as I was done with the hook,

guess what I did.

Exactly the same thing with the kick.

I've exclusively started working

on those deformation frames using the tweaker bones.

That's pretty important because

they are very easy to use,

and to sculpt those specific impacts.

Then I start working using the blue controllers.

Those are the forward kinematic controls

that will also us to slightly bend the bag.

We could spend hours in the graffiti tool

polishing those controllers,

but instead I've kept the process

as simple as possible,

keying as less frames as possible

and letting blender interpolate between those frames.

So I'm selecting all the controllers from the one,

just upon the impact frame, toward the tip of the bag.

Then make sure that you are using individual origin,

so is that we will be able to bend

all the controller at once.

And just bend the bag toward its previous position,

as if it was dragging as less as possible.

If you bend it too much, it won't look realistic

because it will look too smooth.

From there, if you don't jump into the graffiti tool,

that's gonna be hard to make it look good.

As soon as I reached the next impact frame,

I'm keying the frame before the impact,

and then I'm slightly increasing

the curvature of the bag on the impact.

Then, when the hook is about to happen,

this is the time where the bag is traveling the fastest,

so I will slightly bend it toward, again,

it's previous position.

And this is all you create

this subtle dragging, almost for free.

The trick is to make sure

that you manipulate all the bone

in the chain at the same time.

Since they have a parent and child relationship,

you rotate the parent,

that makes the child rotating too,

and then you apply on top of this

a bit of rotation on the child, et cetera, et cetera.

It generates a slight bend in the bags

that looks very natural.

The only moment where I had to be

a little more creative was on the kick,

where I posed the bones frame by frame.

On the frame prior to the kick,

I've just made the whole bag dragging.

And then, on the impact,

I first made the top part of the bag

to rotate the right, behind the leg of the character

while the lower part of the bag will be dragging.

So I will invert it's rotation

and rotate it a bit backwards.

Since the bag is arriving very fast

and we kicking it the opposite direction,

there is a lot of deformation in the bag.

Then, as it is projected by the kick,

I will slightly bend it backward

toward its previous position

to make it drag a bit.

Finally, as as it hits the ground,

I bend it toward its previous direction

so is that it is dragging again.

And then I will console the rotation

a couple of frame after

and convert all the landing keys

and the keys after to vectors

so that I have a hard slap on the ground.

One final touch I've added is that

I've used the tweaker control root

to squash the bag on the ground.

In the end, it's barely noticeable,

because I've kept it very subtle.

I selected all the tweaker bone,

inserted a key frame on the key prior

to squash the bag so that I don't get any

weird interpolation,

then I've scaled them up a bit

on the X and Y axis, and flatten it,

scaling it down on the Z axis.

Then two or three frame later,

I've consoled any scale by pressing alt+S.

One final detail I have revised,

but I'm not sure I've captured it,

is the rotation of the bag

just after the right cross.

I've slightly lowered the level of rotation

of the bag so that it stays on screen

while we are rotating around the character.

This is typically the kind of detail

I wouldn't have taken care of a year ago,

for example, but it's very important because

it does improve the readability of your animation.

This is typically the kind of detail

that will bring you to a professional level of animation,

because it shows that you care for your audience,

and make sure that they will get

everything about your animation.