GltfAnimation

public final void addAnimationStateListener(
    @NonNull Consumer<@NonNull GltfAnimation.AnimationState> listener
)

Registers a listener to be invoked on the main thread when the animation state of the GltfAnimation changes.

public final void addAnimationStateListener(
    @NonNull Executor executor,
    @NonNull Consumer<@NonNull GltfAnimation.AnimationState> listener
)

Registers a listener to be invoked when the animation state of this GltfAnimation changes.

@MainThread
public final @NonNull GltfAnimation.AnimationState getAnimationState()

The current state of this animation.

@RequiresApi(value = 26)
public final @NonNull Duration getDuration()

The duration of this animation.

public final int getIndex()

The index of this animation in the source glTF model.

@MainThread
public final boolean getLoop()

Whether this animation should loop when playing.

The default value is false (playback does not loop). When looping is disabled (false) and playback reaches the end of the animation, the animation state transitions to AnimationState.STOPPED, while remaining clamped at the final frame pose.

Changes to the loop configuration only take effect during start. Modifying this property while the animation is actively playing is currently not supported. The setter will remain annotated with ExperimentalGltfAnimationApi until dynamic loop updates during active playback are supported.

public final String getName()

The name of this animation, or null if the animation is unnamed.

@MainThread
public final float getSpeed()

The playback speed multiplier for this animation.

This can be changed while the animation is playing or paused.

The default playback speed is 1.0f. The speed multiplier determines the playback rate:

• 1.0: Normal speed.

• > 1.0: Faster playback.

• > 0.0 and < 1.0: Slower playback (e.g., 0.5 is half speed).

• 0.0: Freezes the animation at the current frame while keeping it active (unlike pausing).

• < 0.0: Plays the animation in reverse.

Note on Reverse Playback: When playing in reverse without looping (loop set to false), starting the animation from the beginning causes it to reach the end of playback immediately. Enable looping via loop (setting loop to true) to play the animation in reverse continuously.

@MainThread
public final void pause()

Pauses this animation.

This freezes the animation at the current frame and transitions the animation state to AnimationState.PAUSED. Use resume to continue playback.

Note: Calling start while in the AnimationState.PAUSED state will reset the playback time to the start of the animation, and transitions the state to AnimationState.PLAYING.

public final void removeAnimationStateListener(
    @NonNull Consumer<@NonNull GltfAnimation.AnimationState> listener
)

Unregisters a previously registered animation state update listener.

@MainThread
public final void resume()

Resumes this animation.

This continues the animation from the point where it was paused and transitions the animation state to AnimationState.PLAYING.

Note: Calling resume while in the AnimationState.PLAYING and AnimationState.STOPPED state will have no effect.

@RequiresApi(value = 26)
@MainThread
public final void seekTo(@NonNull Duration time)

Seeks this animation to the specified time offset.

@MainThread
@ExperimentalGltfAnimationApi
public final void setLoop(boolean value)

Whether this animation should loop when playing.

The default value is false (playback does not loop). When looping is disabled (false) and playback reaches the end of the animation, the animation state transitions to AnimationState.STOPPED, while remaining clamped at the final frame pose.

Changes to the loop configuration only take effect during start. Modifying this property while the animation is actively playing is currently not supported. The setter will remain annotated with ExperimentalGltfAnimationApi until dynamic loop updates during active playback are supported.

@MainThread
public final void setSpeed(float value)

The playback speed multiplier for this animation.

This can be changed while the animation is playing or paused.

The default playback speed is 1.0f. The speed multiplier determines the playback rate:

• 1.0: Normal speed.

• > 1.0: Faster playback.

• > 0.0 and < 1.0: Slower playback (e.g., 0.5 is half speed).

• 0.0: Freezes the animation at the current frame while keeping it active (unlike pausing).

• < 0.0: Plays the animation in reverse.

Note on Reverse Playback: When playing in reverse without looping (loop set to false), starting the animation from the beginning causes it to reach the end of playback immediately. Enable looping via loop (setting loop to true) to play the animation in reverse continuously.

@MainThread
public final void start()

Starts playing this animation.

This transitions the animation state to AnimationState.PLAYING. By default, the animation plays once at normal speed (1.0f) without looping unless configured otherwise via loop and speed. Calling start while the animation is currently playing or paused will restart playback from the beginning.

@RequiresApi(value = 26)
@ExperimentalGltfAnimationApi
@MainThread
public final void start(@NonNull GltfAnimationStartOptions options)

Starts playing this animation with the specified options.

@MainThread
public final void stop()

Stops this animation.

This resets the playback time to 0 and transitions the animation state to AnimationState.STOPPED. If this animation is not currently playing or pausing, this method has no effect.