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[edit] NLA Editor

[edit] Description

You use the NLA Editor to mix actions and IPOs of objects to make a composite animation. Both Object Ipos and Actions can be blended. Every object may have only one composite animation.

The NLA Editor works in two different modes. In the "Action" (single) mode only the current active action is played. To play combined action use the "NLA" (combined) mode.

In the NLA Editor you see a representation of all Objects with either Actions or Ipos. On a per Object basis, you can add "Action Strips" with Shift A; you can add as many Actions as you like, allowing you to mix different Actions to non-destructively edit timing and relationships. Each Object can have only one active Action, which is displayed in the Action Editor. This active Action is the one which will receive any new keys you insert, and whose keys you can directly edit.

When strips are inserted, they start at the current frame. When a strip is added, it becomes the active strip. The current active strip is always drawn in yellow. Clicking on a strip itself or on the left-hand bars will make the strip active.

You add new Ipo-Keys to the active Action, you can directly edit these Keys (delete, move). The objects you select in the NLA window are selected also in the 3D window.

Ipo's for objects - and also for armature objects - can be converted to Actions in the Ipo window.

1. An object is only shown in the NLA editor window if it has Ipos, an action, or NLA strips. The top-most horizontal bar for an individual object shows the Object's name to the left, and any Object Ipo "keyblocks" (the diamonds that represent keyframes) on the right. (Image 9 - the "Lamp" has only object Ipo's, and no Actions).
2. The button to the immediate left of the Object name toggles Blender between evaluating the entire NLA and displaying the results in the 3D window, or only evaluating the active Action (Image 9 - "Camera" is in "Action" mode, while "AR-right" and "AR-left" are in "NLA" mode).
3. Immediately below the first Object bar, the active Action is shown, and the "keyblocks" for the Action's Ipo's.
4. Finally, the "Action Strips" are drawn. The active Action Strip is indicated with a black dot icon. Clicking on a Strip itself or on the left-hand bars will set a Strip to being the active Action.

[edit] NLA Strip Options

[edit] Description

After an action strip has been added to the NLA Editor, various options are available to determine how it appears in time, and is blended with other strips.

[edit] Options

Timeline Range

The first and last frame of the Strip in the timeline. The Strip length is independent from the length of the Action, but the Action will "stretch" to fill the Strip length.

Locked Strip Length

By setting the strips to Locked, NLA will alway keep strip length up-to-date with your Action edits so that all keys are included.

• Locked mode is the new default, as it is far superior to the old behavior, but older files will have to be updated manually for this feature to work.
• If you release this lock, you can choose only a part of the action to be included in the strip.
• Action End is not allowed to be less than Action Start, so you cannot reverse an action in the NLA editor.

Blending

The number of frames of transition to generate between this Action and the one before it in the Action strip list.

Repeat

The number of times the Action range should repeat.

• Not compatible with Stride Support settings.

Hold

If this is enabled, the last frame of the Action will be displayed forever, unless it is overridden by another Action. Otherwise the armature will revert to its rest position.

Add

Specifies that the transformations in this strip should add to any existing animation data, instead of overwriting it.

Stride Path

Repeats the strip along a path (for example, to make a walk cycle)

Disable Path

Temporarily disables the path movement so you can see your action repeating on the spot

Stride

The distance in Blender Units that the strip should be repeated over (the length of the stride)

X/Y/Z

The axis of the stride bone to move the armature along

Stride Bone

The name of the stride bone. See tutorial NLA Editor and Stride Path -> Example 2: Stride Bone

[edit] NLA Strip Tools

[edit] Description

Edit the properties of the Strips and Keys via the Strip menu:

[edit] Options

Move Up/Move Down

Page Up or Page Down to change the order of the strips. Strips are evaluated top to bottom. Channels specified in strips later in the list override channels specified in earlier strips.

Delete

X Deletes a Strip or a Key. Deleting a Strip affects only the NLA editor. However, if you delete a key the position is permanently gone.

Duplicate

Shift D Copies a Strip or an Ipo.

Snap to Frame

Shift S Snaps start and end of the selected Ipo Strip to frames.

Reset Strip Size

Alt S Resets the size of the Strip in NLA to match the chosen range of frames from Action.

Reset Action Start/End

Alt S Resets the chosen range of Action frames to include all frames in the Action (this is only necessary if you are not using the new "Locked Strip Length" feature, and is useful for fixing older files or if you have "lost your place" when adding or subtracting frames from Actions).

Grab/Move

G Moves the strip horizontally. With Ctrl you move by frames.

Scale

S The base "point" for scaling is the current frame. By setting the frame you can select whether the end, the beginning, or a point in the middle of the strip shall keep its position.

Redirects to fix

• Manual/PartX → Manual/Effects and Physical Simulation
• NLA Editor and Stride Path → Doc:Tutorials/Animation/Armatures/NLA Editor and Stride Path