Struct Timeline 

pub struct Timeline { /* private fields */ }

Prepared tracks for separate Kit elements, using the shared timeline engine. Track insertion allocates; sampling reuses a Kit frame buffer. Retain the timeline, add tracks once, and use now(cx) for playback controls.

Implementations

impl Timeline

pub fn at(&mut self, at: Duration, animation: Animation) -> usize

Adds an absolute track and returns its stable frame index.

pub fn then(&mut self, animation: Animation) -> Result<usize, AnimationError>

Appends after the last finite track. Infinite predecessors return an error.

pub fn label(&mut self, name: impl Into<String>) -> Result<(), AnimationError>

Records a unique label at the current finite sequence cursor.

pub fn at_label( &mut self, name: &str, offset: Duration, animation: Animation, ) -> Result<usize, AnimationError>

Adds a track relative to an existing label, returning its frame index.

pub fn now(&self, cx: &App) -> Duration

Current native timestamp. Returns zero before the first frame call.

pub fn restart(&mut self, now: Duration)

Starts all prepared tracks over using this owner’s clock.

pub fn pause(&mut self, now: Duration)

Pauses all tracks, including delays.

pub fn play(&mut self, now: Duration)

Resumes all tracks.

pub fn seek(&mut self, playhead: Duration, now: Duration)

Holds every track at an absolute playhead, including backward seeks.

pub fn set_speed( &mut self, speed: f64, now: Duration, ) -> Result<(), AnimationError>

Sets a finite rate; negative values play backward.

pub fn sample(&mut self, now: Duration, reduced_motion: bool) -> &[Frame]

Samples one explicit epoch without allocating. Do not mix with native time.

pub fn frame(&mut self, window: &mut Window, cx: &App) -> &[Frame]

Samples native time and schedules even when only a future track is pending.

pub fn is_animating(&self) -> bool

Whether the last sample needs another frame (including future tracks).

Trait Implementations

impl Debug for Timeline

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Timeline

fn default() -> Self

Returns the “default value” for a type.