| On this page |
Pose-to-pose animation ¶
Pose-to-pose animation involves keying the important poses where they occur in time, and then filling in the animation between these key poses. This is the common method for doing 3D computer-based animation.
This is a newer style of animation dating back to the 1960s where the master animator would create main cells (2 or 3 per shot), additional cells (between 5 and 10) would be filled in “from storybook”, and then the remaining in-between cells would be created.
This style involves two phases - blocking and posing.
Blocking ¶
In this phase:
-
Lay out the rough animation by creating the important poses where they occur on the timeline.
-
Set keyframes on everything that is key-able. This is for control and predictability - you don’t want to accidentally leave something un-keyed. This is also much faster than selecting the parameters to key.
-
Use constant (straight) or sometimes linear transitions between keyframes in the animation editor. This makes the character jump between poses.
Keying everything gives quick, immediate results, but it can become difficult to tweak the animation later, especially for complex characters.
To set up Houdini for blocking:
-
Choose Edit ▸ Preferences ▸ Animation.
-
Turn off Auto-Key: Add Keyframes on Parameter Change.
-
Set Global Set Key to Set Keys on All Channels.
-
Create a channel group containing the parameters of the character’s world space controller Nulls. Use the channel group to select the parameters to keyframe.
-
Copy the current pose to create the next pose:
-
Pose the character and key everything.
-
Copy the keyframe in the playbar to another frame and key everything at the new frame. See the playbar help for information on editing keys on the playbar.
-
-
Use flipbook blocking to move the blocked poses around in time.
Posing ¶
In this phase, you clean up the animation by deleting unused animation (delete keys on straight curve segments) and set up transitions between keyframes (convert constant transitions to ease, constant, or spline). As the characters transition between the main poses, you add keyframes for finer controls, keying only the affected parameters.
A good workflow for this phase is to work on the hips down to the feet on the first pass, and the neck down to the arms on the second pass.
In this phase you will often run into a series of diminishing returns for tweaking the character. After much tweaking, making small changes begin to take a lot of effort.
Straight-ahead animation ¶
Straight-ahead animation involves posing the character for every second (“on 2s”), third (“on 3s”), or fourth (“on 4s”) frame on the first pass, then doing “clean-up” passes to fill in additional poses where needed. This is a kind of performance-based animation similar to how one animates in traditional 2D cel animation. This technique is considered fairly advanced; few CG animators work this way. It requires planning ahead, acting ability, understanding of the character, and experience.
To set up Houdini for straight-up animation:
-
Choose Edit ▸ Preferences ▸ Animation.
-
Turn off Auto-Key: Add Keyframes on Parameter Change (because you are tweaking and keying everything anyway).
-
Set Global Set Key to Set Keys on All Channels.
You do not need to use the animation editor, because you do not need to control the functions in between the key poses. You can use the “Pose” pane layout as-is. You can even hide the take list and parameter editor until you are done the first pass.
You do not need to create channel groups until the clean-up passes.
