Matinee Track Reference

As of Unreal Engine 4.24, you can no longer access the Matinee Editor from the Cinematics Menu and Details Panel. This is part of the transition to remove Matinee from UE4 completely in 4.25. You can still convert Matinee actors to Sequencer assets using the Matinee to Sequencer Conversion Tool.

Matinee provides many built-in Track Types that allow for animating different types of data on various types of Actors. Through the use of Tracks you can dictate movement of Actors around in a scene, fire off events in Blueprints, adjust color or material properties of an Actor, as well as several other elements which are covered on this page.

Movement Track

One of the most important Track classes is the Movement Track which is used to move an Actor around in the scene over time. A prime example of this would be to generate a path for an Actor to follow. Creating a path is simply a matter of selecting the Movement Track you want to modify and doing the following:

• Scrub to the time when you want to add the new keyframe.
• Press the Enter key or the Add Key button to create a new keyframe at that time.
• Move the Actor to the desired position for that frame.
• Repeat this for each keyframe and desired position in order to create your path.

It is a very good idea to create an initial keyframe for the Actor at its initial position at level load and then not move that keyframe. Otherwise you may see a "pop" when playback begins as the Actor moves to the position proscribed by the animation data.

You will see the path of the Actor in the 3D viewport. Paths are drawn in yellow when the Group is selected and are set to the Editor Group color when unselected. You can Left-click on the large keys (larger boxes) in the 3D viewport to select a key and allow you to edit it in the same way as you would select them in the main Matinee window. The smaller boxes (or Ticks) indicate 0.1 second intervals, and so give you an idea of the speed of the object.

When a keyframe is selected, you will see green handles in the level viewports which allow you to control the velocity at that key and reshape the curve. By default the interpolation mode between keyframes is a curve, but you can change the interpolation mode by Right-clicking on a key in the main Matinee window and using the Interp Mode menu.

The color of the keyframe triangle in the Matinee window will indicate the current interpolation mode it is using.

Below are the Properties that can be adjusted for this Track from the Details panel.

Refer to Setting Up a Door and Setting Up Lifts for examples of using the Movement Track to move Actors in a scene.

Rotation Interpolation

Matinee uses two different rotation interpolation schemes to rotate Actors between keyframes: Euler and Quaternion.

• Euler - This is the default and works by interpolating the Yaw, Pitch, and Roll of the Actor between the values at keyframes. This allows you to edit the 3 curves for orientation over time in the Curve Editor and control ease-in/ease-out between keyframes. It also supports winding - that is, if you rotate an object multiple times around, the keyframe will store the number of complete revolutions instead of throwing it away. This makes it easy to keyframe something like a screw going into a wall, and also gives you complete control over which direction an Actor takes when moving between two orientations.

• Quaternion - This method of interpolation does not support winding, and is essentially linear between keyframes with no support for ease in/out. However, it is more robust and will always find the "shortest" route between two different orientations.

You can control which method is being used by toggling the Use Quat Interpolation setting from the Details panel.

Rotation Modes

There are two different Rotation modes in Matinee: Keyframed and Look At Group.

• Keyframed - is the default, where the orientation of the Actor is determined by keyframes.
• Look At Group - specifies that you want the Actor to always point at the Actor controlled by another Group.

Look At Group is useful when using a camera, as you can have it always look at a particular target wherever it moves. To use Look At Group as the Rotation Mode, type into the LookAtGroupName field the name of the Group you wish the Actor to point at, and set the RotMode setting to IMR_LookAtGroup.

Movement Relative To Other Groups

It is possible to have a Movement Track keyframe lookup its transformation info from another Group in the same Matinee sequence.
This means that a keyframe can point to a moving object and have the Movement Track interpolate to that position.
An example usage case of this would be animating a projectile that always hits a character moving in a non-predictable fashion.

To setup a keyframe to lookup its position from another Group, Right-click on the keyframe and choose Select Transform Lookup Group....

This will show a dialog that lets you choose a Group to lookup transform information from.

After selecting a Group, the keyframe will have the lookup Group's name displayed above it.
The image below displays 4 key frames that are using the Group's Box1 and Box2 to lookup their positioning info.

To clear a lookup Group for a keyframe, Right-click on the keyframe and choose Clear Transform Lookup Group.

Separating Translation and Rotation

It is possible to "split" a Movement Track's translation and rotation components so they can be keyframed individually on each axis.
This allows finer control over Movement Track curves. Splitting a Movement Track is an opt-in process.
Initially, all Movement Tracks are combined which means translation and rotation curves have the same number of keyframes and all keyframes exist at the same location in time.

To split a Movement Track, simply select Split Translation and Rotation from the context menu when Right-clicking on a Movement Track.

Once you split a Movement Track, it will look like this:

Each axis operates like a unique Track so you can have any number of keyframes in them.

Translation and rotation components are grouped and can be collapsed when not in use. The vertical bars drawn adjacent to the translation and rotation groups represent a keyframe in one or more of the axes. Selecting a vertical bar will select all keyframes below it. This allows you to select multiple keyframes at once.

Quaternion interpolation mode cannot be used when translation and rotation are separated.

Normalize Velocity

When working with Bezier curves, it is often possible to create situations where objects traveling along a curve speed up or slow down depending on the shape and spacing of keyframes. The Normalize Velocity option modifies a Movement Track's translation curves in order to make objects traveling along it move at constant velocity.
It is important to understand that constant velocity uses the 3D path that your Movement Track curves generate. When normalize velocity is used, the 2D curves for each axis of translation may change shape but the 3D path that it generates should not change from the original path.

Normalize Velocity does not force a curve into constant velocity after the menu option is selected.
It simply does a one time adjustment by examining the original curves and modifying them to maintain constant velocity.
Any subsequent changes to the curve may cause it to no longer have constant velocity. Normalize Velocity is also only available on Movement Tracks which have translation and rotation separated (see Separating Translation and Rotation above).

It is possible to Normalize Velocity on segments of a curve rather than the full interval. When this happens, the Normalize Velocity routine adds a keyframe right before and right after the section being normalized. This is done so that the parts of the curve not being normalized remain intact. You may notice "jerky" movements during playback when an object traveling along the curve transitions to and from the Normalized Velocity section. To fix this, you will have to manually adjust the keyframes before and after the normalized segment.

The Director Group

The Director Group is a special type of group that does not work on an arbitrary Actor in the scene like a normal Actor, but implicitly works with the "Player". It is used when you want your sequence to be a cinematic, and you want to take control of the players view.

You can add a Director Group to your Matinee sequence in the same way as a regular group, but choose Add New Director Group instead. The Director Group header is a different color from a regular group header to make it easier to find.

The Director Group has a set of unique Track Types that can be added which are outlined below.

Director Track

The Director Track allows you to attach the players view to different Actors as the sequence proceeds. When you add a new keyframe to the Director Track, a combo box will allow you to choose which Group to assign the view to at that point.

Colored bars on the Director Track allow you to see which Group the camera is viewing through at each point in the sequence - the color corresponds to the Editor Group color of each group.

If you want to return the camera to the player, simply add a cut back to the Director Group itself (think of the Director Group as a special group relating to the "Player"). At the end of the sequence, the view will automatically return to the player so a cut back to the Director Group is not necessary.

Shots

Director Tracks are broken up into named Shots, just as you would encounter in standard film-making. Each key denotes a new shot and the shot lasts for the duration of that key.

By default, shots are numbered according to their position in the timeline. Adding a new key between two existing keys will cause the shot associated with the new key to be numbered between the existing shots.

Existing keys:

After adding new key:

Shots can be renamed through the context menu.

1. The existing shot name:
   
2. Select the key the shot is associated with, Right-click on it, and choose Rename in the context menu.
   
3. Enter a new number for the shot in the Set Camera Shot Number dialog:
   
4. The shot is now renamed:
   

Fade Track

To control fading of the scene to a particular color, you can use a Fade Track. In order to control the amount of fading over time, you must use the Curve Editor. When the Fade amount is 0.0, there is no fading, and when its 1.0, the scene is completely faded out.

Below are the Properties that can be adjusted for this Track from the Details panel.

Slomo Track

One special effect you can apply to a cinematic is to slow down the game speed by using a Slomo Track. This Track works similarly to the Fade Track where you use the Curve Editor to modify the slow-motion over time. A Slomo factor of 1.0 will use the default game speed, a lower number will reduce game speed and a higher number will speed up the game.

Slomo affects all game actions, physics, particles, etc. as well as the speed of the sequence itself.

Below are the Properties that can be adjusted for this Track from the Details panel.

Audio Master Track

The Audio Master Track gives control over the overall volume and pitch of the game's audio. When an Audio Master Track is added to the Director Group, it has one default key at the beginning of the sequence whose InterpMode is Linear. Adding new keys allows you to modify the volume and/or pitch over the course of the sequence.

Below are the Properties that can be adjusted for this Track from the Details panel.

Color Scale Track

The Color Scale Track modifies the color scale of the rendered scene output, allowing you to tint the scene.

Below are the Properties that can be adjusted for this Track from the Details panel.

Property Tracks

Property Tracks consist of several different Track Types and contain a variable inside the Actor the Track is attached to. You can set new variable values for a Property Track by Right-clicking on a keyframe and choosing the Set action that corresponds to the Track Type selected.

Before a Property Track can be added to Matinee however, it must first be "exposed" so that Matinee can affect it.

Exposing Tracks To Matinee

Exposing a variable to Matinee can be accomplished by selecting the Expose to Matinee checkbox inside the Details panel of the Blueprint the variable resides in, as pictured below.

Once you have compiled your Blueprint, the variable type can be used as a Track Type in Matinee.

To expose a variable in code, simply add Interp as a keyword in the UPROPERTY() macro.

While most Tracks can be added and worked with instantly, the following Track Types are required to be exposed to Matinee (or through code) in order to work with them.

Bool Property Track

The Bool Property Track provides control over a boolean variable in the Actor connected to the group containing the Track. When adding the Track, a dialog will appear allowing you to choose from all boolean variables that are connected to the Actor that can be controlled by Matinee.

Below are the Properties that can be adjusted for this Track from the Details panel.

Float Property Track

The Float Property Track allows you to modify the value of a floating-point property of an Actor over time, such as Brightness for a light, or DrawScale for a StaticMesh Actor. When you create the Track, it will bring up a combo box showing all modifiable properties of that Group's Actor. Select the one you want and then add/modify keyframes in the same way as you would for a Movement Track. You can also use the CurveEditor to adjust the value of the parameter over time.

Below are the Properties that can be adjusted for this Track from the Details panel.

Vector Property Track

The Vector Property Track allows you to modify the value of a Vector property of an Actor over time, such as DrawScale3D for a StaticMesh Actor. When you create the Track, it will bring up a combo box showing all modifiable properties of that Group's Actor. Select the one you want and then add/modify keyframes in the same way as you would for a Movement Track. You can also use the CurveEditor to adjust the values of the parameter over time.

Below are the Properties that can be adjusted for this Track from the Details panel.

LinearColor Property Track

The LinearColor Property Track is used to modify a linear color variable in the attached Actor. For example, if you have a Light Component as part of a Blueprint, you can assign a linear color variable as the light's color and can then change it using this type of track. The components of a linear color take values in the range 0 to 1 (or higher to overdrive the component).

Below are the Properties that can be adjusted for this Track from the Details panel.

Color Property Track

The Color Property Track is used to control a byte-based Color variable in the attached Actor. For example, unlike the LinearColor Property Track, if you were to place a Light Actor directly inside a level, you would then be able to adjust the Light Color property via this type of track.

Below are the Properties that can be adjusted for this Track from the Details panel.

Material Parameter Tracks

There are two Material Parameter Tracks that can be driven by Matinee: Float Material Parameter and Vector Material Parameter.

Float Material Parameter Track

The Float Material Parameter Track is used to modify Scalar Parameters within materials during runtime. The Track takes a list of materials and modifies the value of the given parameter in those materials.

Below are the Properties that can be adjusted for this Track from the Details panel.

Vector Material Parameter Track

The Vector Material Parameter Track is used to modify Vector Parameters within materials during runtime. The Track takes a list of materials and modifies the value of the given parameter in those materials.

Below are the Properties that can be adjusted for this Track from the Details panel.

Particle Tracks

There are two Particle Tracks that can be driven by Matinee: Float Particle Parameter Track and Particle Replay Track.

Float Particle Parameter Track

The Float Particle Parameter Track is used to modify parameter distributions within particle systems during runtime. Any parameters with the given parameter name in the particle system connected to the group containing the Track will be modified. This means you could have a fire particle system with emitters for the flames, sparks, and smoke where each emitter has a parameter controlling the spawn rate named SpawnRate. A single Float Particle Param Track could drive all of these parameters to control the fire.

Below are the Properties that can be adjusted for this Track from the Details panel.

Particle Replay Track

The Particle Replay track allows you to create and play back pre-recorded particle simulations. This is especially useful when you want the particle to behave the same way in all shots. When you add a new key to the Particle Replay Track, you are essentially adding a new clip to record to. For each clip, a bar is displayed on the timeline showing the duration of the clip.

When selected, you have the ability to adjust the starting point and duration of the clip using the handles on either end of the clip's bar in the timeline. Left-clicking and dragging the mouse on either handle will adjust the duration of the clip by moving that handle. To move the clip without adjusting its duration, Ctrl+Click and drag on the key itself.

You can also adjust the starting position and duration of the clip as well as change the ID of the clip by Right-clicking on the clip's bar in the timeline and choosing the appropriate option from the menu.

To begin recording the particle system(s), Right-click on the track and choose Start Recording Particles from the context menu.

When recording is active, the clip bars will be highlighted in the timeline.

Press the Play button in the toolbar to begin playback. The track will record the particles during play back when recording is enabled. Once recording is finished, Right-click the track again and choose Stop Recording Particles.

Now, when you press the Play button, the particle system(s) should play back from the recorded clips and you can scrub through the timeline to move forward and backward through the clips to inspect the recording.

Animation Track

The Animation Track allows you to animate the properties of Actors over time, to create either dynamic gameplay or cinematic in-game sequences. Through the use of this Track Type, you can place keyframes to control when and how they play specified animations.

To add an animation to the Track, scrub through the Track and press the Enter key or Add Key Button. When a key has been added, you will be prompted to select an animation to add to the track through a pop-up window as shown below.

Once an animation has been added to the Track, it will be displayed in Blue. You can manipulate the animation by Left-clicking the key to select it.

With the animation selected, you can adjust the length by moving the cursor to the start or end point until the double-arrows are shown as seen below and dragging in either direction.

You can also move the position of the animation on the track by Control+Left-Clicking on the animation and dragging it along the Track.

The numbers shown on the animation illustrate the (Start->End) times in which the animation will play. The number following the Start/End times (x0.89 for example), indicate the playback rate of the animation where 1.0 is the default and higher numbers increase the speed of the playback while lower numbers decrease the speed. To adjust playback rate, hold Control when adjusting the length of the animation.

Below are the Properties that can be adjusted for this Track from the Details panel.

Event Track

The Event Track gives Matinee a mechanism for firing events back into Blueprints at particular points in the sequence. When you place a keyframe on an Event Track, you will be asked for an Event Name. Each unique Event Name will create a new output connector on the Matinee Actor. When the sequence reaches the key, any Blueprint nodes that are connected to the output will be activated. If you have multiple keys with the same name, one output connector will be created, but it will be activated when each of the keys are passed.

Here is an Event Track with one key called "ToggleLight".

And this is the Matinee Actor in a Blueprint, showing the new output connector which you can connect to fire off events.

The buttons on the Event Track header allow you to control if the output should be fired when the sequence is playing forwards, backwards, or both. If the right arrow button is yellow, events on that track will fire as they are passed when the sequence is playing forwards. If the left arrow button is yellow, events are fired when the sequence is played backwards.

Regardless of which group the Event Track is in and whether or not an Actor is attached to the group; the Matinee Actor will create an output connector for each key placed on its Track. You can also Right-click on a key to rename it and doing so will rename any other keys with the same name, as well as the output connector on the Matinee Actor.

Below are the Properties that can be adjusted for this Track from the Details panel.

Sound Track

The Sound Track is used to play audio from SoundCues during a Matinee sequence. When placing a new key, the SoundCue currently selected in the Content Browser will be used. Keys for the Sound Track appear similar to those of the AnimControl Track. You will see a bar with the name of the SoundCue that stretches for the duration of the SoundCue.

Below are the Properties that can be adjusted for this Track from the Details panel.

Toggle Track

The Toggle Track gives Matinee a mechanism for toggling Emitter Actors on or off at particular points in the sequence. When you place a keyframe on a Toggle Track, you will be presented with the following dialog:

The options are:

• Trigger - A one-shot activation of the particle system.
• On - Turns the particle system on.
• Off - Turns the particle system off.

The Track display will show a green bar when an emitter is toggled on to make it easy to identify the state of the Actor. This can be seen below for a Toggle Track that turns the emitter on and back off again.

Below are the Properties that can be adjusted for this Track from the Details panel.

Visibility Track

The Visibility Track is used to control whether an Actor is visible or not (by way of the Actor Hidden In Game property). When adding a new key for this Track, you are presented with a dialog with options to Show, Hide, and Toggle the associated Actor.

The Track display will show a green bar when the Actor is set to visible and later set not visible again to make it easy to identify the state of the Actor. This can be seen below for a Visibility Track that shows the Actor for 1 second then hides it.

Keys set to toggle the visibility of the Actor are displayed with a small red bar to denote them as toggle keys.

Below are the Properties that can be adjusted for this Track from the Details panel.