Original subtitles

- [Instructor] In this video,

we are going to polish the torso of the character.

Since it's pretty subtle on the run cycle,

especially for a light character,

I like to start with the left to right location motion.

So basically whenever your character

is contacting with the crown,

the contacting leg will first absorb the impact

and then push the character up,

but also a bit on the opposite side.

Your character should be moving to what the contacting foot

one or two frame after the contact,

so that he has time to compensate the momentum

of the previous move.

Then there will be an acceleration during the pushing

toward the other side.

And when the character is airborne,

my go-to is to use a linear curve.

But there won't be any noticeable dumping

while your character is in the air.

There is no opposite force to absorb the momentum

of the side to side motion.

So in our case, the contacting frame is frame two

and frame 14, then takes two frame to get to the extreme.

And then as the character is pushing,

his body is moving on the other side.

Once you are done with the side to side motion,

we can work on the forward and backward motion.

People, and myself included, often forget to add forward

and backward motion to the torso root.

It's not a big deal if you forget to,

as it's gonna be pretty subtle,

But this slight variation will bring a bit of texture

to your run cycle.

The rule is pretty simple.

As your character is falling forward,

as the torso is getting down,

his torso root will slightly shift forward.

During the pushing pose and while he's airborne,

torso root will slightly travel backward.

So if you have a look to the Y curve,

you can see that the values we are working with

are very, very subtle.

So whenever you are checking the curve as a reference,

don't forget to check out the values on the left side.

To make the X rotation motion a little more obvious.

I've parented this stretched tube to our torso controller.

If you focus on the tip of this tube,

you will be able to clearly see the rotation motion.

The X rotation drives the leaning forward and backward

of our character torso root.

What I want to emphasize here is that whenever the character

is pushing on his leg, his torso is leaning forward.

Think of a lion jumping, pushing on his root

with his shoulder inward.

Then he will reach his highest point,

and as he fall down, the shoulder or the upper torso

will kind of drag behind the root,

and so, the X rotation will go the other way.

While this rotation motion should be noticeable,

don't over-commit and input too high rotation values,

because on top of this, we will also add rotation

into the chest controller.

And as the chest controller is inside of the torso root,

it will rotate even more.

A quick tip, whenever you are working on a chain like this,

I will deactivate the chest controller,

this way, the upper body rotation of my character

is only driven by our torso root.

And it makes it easier to read the motion.

The second tip regarding this motion

is that since our character is taking two step

during the whole cycle, we just need to work

on all of the cycle, and then we can duplicate the curve

onto frame 12 to 24.

Another good practice I should have shown you

at the very beginning of this video

is to hide the arms of the character.

Since we are not working on the arms at the moment,

they can be a bit distracting and training-wise,

it is good for you to only see the torso,

so that you will get used to its motion.

As usual, we are not into a linear close,

so I will jump onto the hips before I finished

to polish the rotation of the torso root.

The first thing I check is which channel I will need

to twist the hips, and it's the Z quaternion channel.

The twisting is the simplest motion

regarding the hips motion since it follows the legs.

So when the left foot is forward or left leg is forward,

the Z curve is pushed down,

so that the hips are twisting forward on their left side.

And during the passing pose,

the hips will twist the other way.

So we have a pretty smooth curve with a slight plateau,

as we are favorizing the airborne pose of the character.

So it's a moment where the hips are not twisting that much.

And then we transition from one side to the other

during the passing.

The next hips motion we will work on

is the left to right tilting,

and it's one of the most important motion of the hips.

It's not the easiest one to get right,

because too much tilting will look very feminine,

while not enough will look very stiff.

This motion is mainly driven by the Y rotation channel.

And what we do want to emphasize

is the pushing of the legs on the hips.

So I'm slightly reducing the amplitude of the curve

so that I can then re-increase it

during the pushing on frame four.

So we have our contact pose on frame two and frame 14,

and on frame four and frame 16,

we need a quick rotation change or shifting,

this way we can fill the impact of the contacting frame

and the fact that the hips will react with a slight delay.

In between those two impact motion,

the hips are smoothly tilting the other way.

As always, for all our cycle,

just make sure that your frame zero and your frame 24

are the same by duplicating them.

Now our hips motion start to look pretty good.

We can now polish the body, X rotation axis,

which will be the tilt forward and backward.

This one is pretty easy to get right.

As the leg reach the contact pose

and switch to the passing pose, the hips will tilt forward.

And then during the pushing and the airborne,

they will tilt backward.

Just imagine that the hips

are currently pulling the front foot,

so when contacting the ground,

the hips will surge forward for the foot,

and then when pushing and going up,

they will pull the foot back.

This motion is linked to the extradition of the top,

so we have already polished it,

so you can keep it very subtle.

Again, don't forget to double check the graph editor values.

While the X rotation curve looks pretty contrasted,

the range of value we are working on is very small,

so in the end, the X rotation is not that big.

As we have slightly modified the orientation of the hips

during the motion, we can see that on the contacting pose,

the leg are not full straight.

While it may look a little more natural,

as explained in the beginning of this chapter,

it's better to have an exaggerated pose for the contact.

So I'm just getting back to both foot controllers,

and I'm slightly offsetting the Y location curve

on the contact frame for both feet.

As our hips are now polished,

we can jump back onto the torso controller,

work on the zero rotation channels,

that is the twisting of the body,

but will be very close to what we have

on the zero rotation of the hips.

They will be just out of frame of delay

compared to the hips twisting.

But the torso twist and the hips twist

are kind of the same behavior.

The fast twisting during the passing,

where I switch from one side to the other,

and then some kind of plateau

where we have a slight overshoot

when our character is airborne.

Once you are done with the twisting motion,

there is a bit of tilting left to right also.

So we have to play on the Y quaternion rotation.

I do advise you to keep it super subtle,

because if you push the tilt left to right too far,

your character will look out of balance

or its run cycle will look a bit sloppy.

That could be a good call for a Hulk-ish kind of run cycle

or a knock or a big barbarian,

but for our character, that would be too much.

So in the end, you can see that the range of motion

is pretty limited, and I'm just smoothing the curve.

The W rotation has almost no influence,

so I haven't worked on this curve.

And in the next video, we will work on the chest controller,

the neck and the head.