Timeline Playback Controls
To play the Timeline instance and to control the location of the Timeline Playhead, use the Timeline Playback Controls.
Timeline Start button
To move the Timeline Playhead to the start of the Timeline instance, click the Timeline Start button, or hold Shift and press Comma (,).
Previous Frame button
To move the Timeline Playhead to the previous frame, click the Previous Frame button, or press Comma (,).
Timeline Play button
To preview the Timeline instance in Timeline Playback mode, click the Timeline Play button, or press the Spacebar. Timeline Playback mode does the following:
在时间轴播放头的当前位置开始回放，并继续到时间轴实例的末尾。如果启用了 Play Range 按钮，则回放将限制在指定的时间范围内。
时间轴播放头位置沿时间轴实例移动。Playhead Location 字段根据时间轴设置以帧数或秒数显示时间轴播放头的位置。
要暂停回放，请再次单击 Timeline Play 按钮，或按空格键。
When playback reaches the end of the Timeline instance, the Wrap Mode determines whether playback should hold, repeat, or do nothing. The Wrap Mode setting is a Playable Director component property.
Timeline Playback mode provides a preview of the Timeline instance while in the Timeline window. Timeline Playback mode is only a simulation of Play Mode in the Game View.
The Timeline Playback mode does not support audio playback. To preview a Timeline instance with audio, enable the Play on Awake option in the Playable Director component and preview game play in Play Mode.
Next Frame button
To move the Timeline Playhead to the next frame, click the Next Frame button, or press Period (.).
Timeline End button
To move the Timeline Playhead to the end of the Timeline instance, click the Timeline End button, or hold Shift and press Period (.).
Play Range button
Enable the Play Range button to restrict playback to a specific range of seconds or frames. You can only set a play range when previewing a Timeline instance within the Timeline window. Unity ignores the play range in Play Mode.
The Timeline ruler highlights the play range and indicates its start and end with white markers. To modify the play range, drag either marker.
Use Play Range Mode, in the Timeline Settings, to set whether the play range plays once or repeatedly.
Timeline Playhead and Playhead Location field
The Timeline Playhead indicates the exact point in time being previewed in the Timeline window. The Playhead Location field expresses the location of the Timeline Playhead in either frames or seconds.
Use the Zoombar to navigate, scroll, and zoom the Clips view. A white line indicates the location of the Timeline Playhead in relation to the entire Timeline instance.
To jump the Timeline Playhead to a specific time, click the Timeline ruler. You can also enter the time value in the Playhead Location field and press Enter. When entering a value, frames are converted to seconds or seconds are converted to frames, based on the Timeline settings. For example, if the Timeline ruler is expressed as seconds with a frame rate of 30 frames per second, entering 180 in the Playhead Location field converts 180 frames to seconds and moves the Timeline Playhead to 6:00. To set the time format that the Timeline window uses, configure the Timeline Settings.
Switching between Local and Global
Use the Local or Global button to change the Timeline ruler from local time to global time. Local time and global time are only relevant when editing a nested Timeline instance.
To create a nested Timeline instance, drag a GameObject associated with a Timeline instance into another Timeline instance. The Timeline instance you are dragging into becomes the master Timeline instance. The Timeline instance associated with the GameObject becomes a nested Timeline instance.
To edit a nested Timeline instance, double-click the Control clip that contains the nested Timeline instance. The Timeline window switches to the nested Timeline instance, indicated by the Timeline title which shows the name and GameObject of the master Timeline instance, followed by the name and GameObject of the nested Timeline instance.
When editing a nested Timeline instance, click Global to switch the Timeline ruler to Local time. Local time is relative to the nested Timeline. This means that the Timeline ruler starts at zero.
Click Local to view the Timeline ruler in relation to the placement of the nested Timeline in the master Timeline instance. This means that if, for example, if the Control clip is placed at frame 70 of the master Timeline then the Timeline ruler starts at 70 at the beginning of the nested Timeline instance.
