Struct VelocityTracker 

pub struct VelocityTracker { /* private fields */ }

The shared animation layer — physics, curves, driver — see frus_core::animation. Re-exported here so applications can reach it through frus_widgets without depending on frus-core directly. A rolling history of pointer positions that can be asked for a velocity.

Adding a position is cheap; asking for the estimate is not free (the regression strategy solves a small system), so ask once, at the release.

Implementations

impl VelocityTracker

pub fn new(strategy: VelocityStrategy) -> VelocityTracker

A tracker using strategy.

pub fn platform_default() -> VelocityTracker

The strategy the running platform reads flings with.

Resolved at compile time from the target, like the scroll physics it feeds: a build is for one platform.

pub fn strategy(&self) -> VelocityStrategy

The strategy in force.

pub fn add_position(&mut self, time: f32, point: Point)

Records where the pointer was, and when (in seconds).

pub fn clear(&mut self)

Forgets everything — a new gesture starts from nothing.

pub fn estimate(&self, now: f32) -> Option<VelocityEstimate>

The estimate as of now (seconds, same clock as the samples), or None when not a single position has been recorded.

pub fn velocity(&self, now: f32) -> Velocity

The estimated velocity as of now, or Velocity::ZERO if there is nothing to go on.

Trait Implementations

impl Clone for VelocityTracker

fn clone(&self) -> VelocityTracker

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for VelocityTracker

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

Formats the value using the given formatter.

impl Default for VelocityTracker

fn default() -> VelocityTracker

Returns the “default value” for a type.