Timeline Editor

Use a Timeline to change a property over a fixed interval. A two-second fade, for example, has an opacity key at the beginning and another at the end.

Prerequisites

Show Advanced resources and open a Timeline. Prepare an Object and attached Logic for the runtime check. Choose a property that the target supports; a track cannot give an Object a component it doesn’t have.

Add Keys

1. Set Duration (s), starting with 2. Leave Loop off for the first check and Speed at 1.
2. In Design, add a track for the property you want to animate. Use the picker to select a supported property or declared state.
3. In Animate, add a key at time 0 and set its Value. Add another key at time 2 with a different value.
4. Select the first key and choose Ease (leaving). This easing governs the segment toward the next key. Compare linear easing with an eased segment before selecting Custom (Bezier).
5. Scrub and play the Timeline. Save, reopen, and inspect both keys.

Time is in seconds. Keys stay within Duration. Copy/paste, duplicate, nudge, and stretch operations let you retime a selection; stretch changes spacing around its earliest selected time and needs more than one item to have an effect.

Add a Marker and Run It

Add a Marker at a chosen time and give it a named Custom Event. A marker signals a moment; it does not store a continuously interpolated property value. Add a listener for that Custom Event in the target Logic if you want it to cause gameplay.

Use Control Timeline Playback with Operation set to play, select the resource, and choose Scope. The all scope addresses the Timeline’s authored targets; self limits playback to the calling instance. Start At is in seconds. Run the Scene with no other Logic writing the same property. Check the starting value, the middle of the interval, the final value, and the marker listener.

Expected result: the property follows the keys and their easing while playback runs. With looping off, playback reaches its end once. With looping on, check the boundary for a jump between the last and first values. Test stopping and restarting separately; the resource preview does not establish the target’s behavior after cancellation.

Troubleshooting

If nothing changes, confirm the Timeline resource, Applies To target, track property, and whether playback started. An empty track has no values to apply.

If the result differs from the schematic preview, inspect the actual target in Game View. The preview explains interpolation; the runtime adds the target’s Transform, hierarchy, other Logic, and rendering.

If an Event doesn’t arrive, check its marker time and name, the target’s listener, and whether playback reached that time. If the property flickers, temporarily remove competing Actions and restore them after the Timeline behaves as expected.

Use Cutscenes when you need actor, Camera, sound, and Dialogue tracks under one director. See the advanced Action reference for Timeline playback.