Splines

May: Animation

SPLINES + ASSESS 2 RECAP

Here’s a great example of splines and using a layered approach. This sort of technique is good for creature animation and dynamic shots.
http://www.youtube.com/watch?v=Rx64DN6qyd4

TODAYS CLASS

Splines – Bookending Keys
Float and Pop
Keeping Things Simple
Euler Rotations

TODAY

1. Lecture on Splines
2. Lecture on Gimbal Rotation
3. Prac Work Continuing from Assessment 2

FILES

Continue to use your Assessment 2 files

ASSESSMENT 2 RECAP

Great work on the assignments guys, I noticed a huge difference in the poses and acting. And very few if any flat hands!! Well done. Here’s a compilation of some of the picks. I had a few troubles with some files and almost everyone had good pieces so don’t be worried if you don’t have a piece in here.

Overall the successful pieces had Morpheus reacting successfully in each situation, thinking as if he’s alive. The posing was strong and clear and showed character and intent.

SPLINES

At this stage we want to switch back to spline animation on our characters.

Splines can be tricky and often mess the snappy feel of our stepped key blocking. Poses may read less clearly due the extra time of transitions that eat into the keys.

No fear it’s just time to tend to the animation splines and continue to tweak the aniamtion.

Tech Notes

1. Return your default hotkeys to be Automatic in the preferences window.
Window > Settings/Preferences > Preferences
Animation > Default Tangent > Auto (for default in and out)

2. The right click stepped mode in the timeline (to return to stepped keys)
Right click in the timeline > Enable Stepped Key Preview

Time Snap
Make sure time snap is on (magnet icon with ticks below)

Common Graph editor Hotkeys

Scrub Mode
hold the “k” key and left click and drag

Scrub Mode without moving the pose
hold the “k” key and middle click and drag

Move
Switch to move mode (w) then hold shift and middle mouse drag in the desired direction.

Scale
Switch to scale mode (r) then hold shift and middle mouse drag in the desired direction. Will scale from the mouse cursor click as a pivot

Copy And Paste
I recomend changing the paste options to merge

1. go to the graph editor > edit > paste (options)
2. Paste Key Options > Edit > Reset Settings
3. Click on the “Help Images”
4. Paste Method: Click on Merge

Copy = “apple c” on PC it’s “ctrl c”
Paste = “apple v” on PC it’s “ctrl v”

Bookend Keys

For any held pose, we require 2 key frames the first marks the start of the pose the 2nd marks the end.

A good place to start is by making both bookend keys identical and setting them to the “flat” tangent type.

Float And Pop

Float and Pop are the enemies of the spline in our animations. They’re opposites too fast or too slow curves in the animation editor.

Pop is when an object moves too quickly causing a jarring motion. Watch the right leg in this cycle…

Pop Example

YouTube / Toby Morgan – via Iframely

Float is when an object moves in an unatural floating in outer space kind of a way. It’s usually due to bad overshooting/uncontrolled splines in the graph editor.

Watch the right hand in this clip on “there comes a time”. This animator on the 11 second club was asking questions about float with some handy advice here on the 11 second forums.

Float Example
http://youtu.be/nhY6rGzaneQ

Moving Holds

If a character stops completely still in 3d animation they can loose the feeling of life. In the real world there’s usually some subtle movement in people who are still.

This also occurs in stop mo and 2d animation but fr some reason it can be more noticeable in 3d animation. In 2d you can get away with it more easily.

YouTube / ShadowDisturbed – via Iframely

Some styles of 3d animation can get away with perfectly still held poses, but the style of animation must suit. It’s usually very simplified….

YouTube / Pocoyo – via Iframely

High-end 3d animation usually requires more subtlety. Notice how in this Pixar scene the characters rarely stay completely still, there’s usually subtle movement on the characters. But it’s always under control of the animator and never floaty like the characters are in outer space.

Toy Story 3 in Hebrew. Mute the sound and just watch the animation.
http://www.youtube.com/watch?v=cWZNZjSJco0

Subtle animation can be tricky and often requires very small delicate movements. In game animation one of the hardest cycles to nail is the “idle cycles” when the characters have to stand still and do very little. Watch the Pixar clip above in detail to see how very small movements can keep characters alive.

Euler Rotations

Euler rotations or Gimbal Rotations is the method we calculate rotations in Maya. This is what causes the problem called “gimbal lock” and sometimes strange rotations on the in-betweens between our key frames. It’s super important to know as it’s counter intuitive until we understand how it works.

Here’s a whole class on Euler rotations.

Euler Rotation Class

For animators it’s important to know a couple of things, as there’s no easy solution to gimbal problems on tricky areas.

1. The rigger needs to setup a good rotation order for each object. We can change this too but requires some knowledge (see the Euler Class). Good rotation orders help a lot and fix problems before they occur.
2. For big whacky Euler issues we can use the “Euler Filter” in the graph editor
3. Manually fixing bad rotations: A lot of times it’s easiest just to manually fix the rotation problems by eye.
4. You many use another object to rotoscope or use constraints to bake the problem area for a segment of animation to fix or tweak areas of bad in betweens.

These are explained more in the Euler Class notes.

Overlap

Animating Overlap example

Vimeo / Brian Horgan – via Iframely

Instructor

Andrew Silke