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The Non-Linear Animation Window

NLA Toolbar

WindowType

As with every window header, the first button allows you to set the window type.

Full Window

Maximise the window, or return to the previous window display size; return to the previous screen setting (Ctrl↑).

Home

All visible blocks are displayed completely, centered in the window (↖ Home).

Lock

This button locks the update of the 3DWindow while editing in the NLAWindow, so you can see changes made to the Action in realtime in the 3DWindow.

NLAWindow

The NLA Window gives a full overview of all the Objects that have had action strips added to the NLA editor and allows a very fine and flexible control of each action, effectively allowing for action blending somewhat akin to how Relative Vertex Keys work on meshes.

The NLA window presents the time, in frames, on the horizontal axis and one strip for each object, each strip can have as many action substrips as desired.

It is important to have unlinked any normal Action from the armature when working with NLA because normal actions take precedence over NLA controls.

The mouse

LMB

Sets current frame.

MMB and drag

The view is translated.

CtrlMMB and drag

Zoom in or out of the NLAWindow, this happens only horizontally.

RMB

Select an Armature Strip (if clicked on strip name) or an Action Strip (if clicked on it). Use ⇧ Shift to enlarge or reduce the selection (extend select).

⇧ ShiftRMB

Add/remove from selection.

The HotKeys

↖ Home

All visible blocks are displayed completely, centred in the window.

A

Select All / deselect All. If one block is selected, everything is first deselected. It behaves differently depending if the cursor is on the left (selects all armatures) or on the right (selects all actions) of the NLAWindow.

Shift-a

Add an action strip for the currently selected object.

B

Border select. Draw a rectangle with the LMB ; all blocks that fall within this rectangle are selected. Draw a rectangle with the RMB to deselect the blocks.

⇧ ShiftD

Duplicates the selected Action(s). Duplicates are automatically in Grab mode and are assigned to new sub-strips.

G

Translation mode (the Grabber). This works on selected Actions and only horizontally, to change frame. The following options are available in translation mode:

• ↑, ↓, ←, →:

The mouse cursor can be moved exactly 1 pixel with these keys.

• Ctrl:

The Actions are displaced by 1 frame steps.

• ⇧ ShiftCtrl:

The Keys are displaced by 0.1 frame steps.

• Grabber terminates with:
• LMB , Space or ↵ Enter: Move to a new position.
• RMB or Esc: Everything returns to the old position.

NKEY

Brings up the "Numerical" window settings for the selected Action.

• Strip Start and Strip End

defines the Action Strip placement. If the interval is greater than the actual Action duration, the Action is performed slower to match the required duration, otherwise faster.

• Action Start and Action End

defines the Action timeline "Windowing". The Actions are defined in their normal way and their duration is, by default, a "Window" of frames going from first to last key. With these sliders it is possible to vary the Action "Windowing".

• Blendin and Blendout

defines a number of frames at the beginning and at the end of the strip of "Reduced influence" of the Action. By carefully setting these and by letting action strips slightly overlap, you can fluidly blend different actions.

• Repeat makes the strip contain as many copies

of the action as desired. Great for Walkcycles.

• Stride in Walkcycles defines the length (in Blender Units) of

a stride.

• Use Path makes Blender use the Path to which the armature

is parented, and its length, to make the Armature move according to Stride definition.

• Hold the last pose forever, instead of reverting

to the original state.

• Add makes Blending additive.

X

Delete selected Actions.