When modifying keyframes, it is often helpful to have a frame of reference for your curves.
A saved reference of curves lets you compare modified curves to the original curves.
Additionally, a saved reference—known as a curve snapshot—acts as a safety net if you
need to restore a curve’s original state.
To take a curve snapshot
Click the Take/Show Curve Snapshot button in the upper-right corner of the Keyframe
With Take/Show Curve Snapshot enabled, as you move keyframes in the Keyframe Editor,
the original curve—as it appeared when you took the snapshot—retains its color. As long
as you remain in the Keyframe Editor editing the current set of curves with the Take/Show
Curve Snapshot button enabled, the snapshot curve remains available.
New curve (white)
Original curve (purple)
If, after editing a curve, you want to revert to the snapshot, you can do so from the
Animation menu in the Keyframe Editor.
To revert a curve to its most recent snapshot
From the Animation menu in the Keyframe Editor, select Set to Curve Snapshot.
The curve reverts to the state of its last snapshot.
If you leave the Keyframe Editor, or load a different set of curves into the
Keyframe Editor, curve snapshots are taken again, replacing the previous curve snapshots.
Keyframes and Curves