The active time segment specifies a block of working time. You might think of it as a window in time that you use to focus on a specific part of your animation.
You specify the active time segment by setting the Start Time and End Time for the segment on the Time Configuration dialog.
You can change the active time segment whenever you want without affecting the keys you've already created. For example, if you have keys scattered over a range of 1000 frames, you can narrow your active time segment to work only on frames 150-300.
Changing the active time segment has the following effect:
The default setting for the active time segment runs from frames 0 to 100, but you can set it to any range.
You can also increase the active time segment using the track bar.
You use the Re-scale Time button on the Time Configuration dialog to change your entire animation based on the active time segment.
Use Re-scale Time as follows:
Click Re-scale Time and then enter new Start Time and End Time values on the Re-scale Time dialog. When you click OK all the animation in the active time segment is moved and scaled to fit the new Start Time and End Time settings. Any animation outside the active time segment is moved to match the new active time segment boundaries.
For example, say you have an animation from frame 0 to frame 300 and an active time segment starting at frame 100 and ending at frame 200. Use Re-scale Time to set the new Start Time to frame 200 and the new End Time to frame 250. Clicking OK gives you the following result:
You can also rescale the active time segment using the track bar.