Struct Animation 

#[non_exhaustive]
pub struct Animation {
    pub current: AnimValue,
    pub target: AnimValue,
    pub velocity: AnimChannels,
    pub timing: Timing,
    pub started_at: Instant,
    pub last_step: Instant,
    pub from: Option<AnimValue>,
    /* private fields */
}

In-flight animation state for one (node, prop) pair. Stored on crate::state::UiState keyed by (ComputedId, AnimProp).

current is the read-back view consumed by write_prop — for AnimValue::Color that’s u8 rgba. The integrator’s per-frame motion near equilibrium is sub-integer in rgb units (typical vel * dt ≈ 0.1–0.4 once the spring is close to target), so integrating against the rounded view loses fractional progress every frame and the integrator freezes a few rgb units off target. current_precise is the lossless f32 mirror integrators actually read and write across ticks.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

current: AnimValue

Current sampled value — the read-back view write_prop consumes (u8-rounded for colors; see struct docs).

target: AnimValue

Value the animation is heading toward. Must be the same AnimValue variant as current.

velocity: AnimChannels

Per-channel velocity — spring integrator state. Zero for tweens.

timing: Timing

Motion model driving this animation.

started_at: Instant

When the animation (or, after a retarget, the current tween segment) began. Tweens measure elapsed time from here.

last_step: Instant

Instant of the previous Animation::step; the next step integrates now - last_step, clamped to 64 ms.

from: Option<AnimValue>

For tweens, the value at started_at. Springs are fully determined by current+velocity, so from stays None.

Implementations

impl Animation

pub fn new( current: AnimValue, target: AnimValue, timing: Timing, now: Instant, ) -> Self

Start an animation at current heading toward target, with zero initial velocity and clocks set to now.

pub fn retarget(&mut self, target: AnimValue, now: Instant)

Re-target a running animation. Current value and velocity carry over so interrupted motion eases from where it is, not from rest. For tweens, from snaps to the current sample so the new curve starts there; the tween clock resets.

pub fn settle(&mut self)

Snap to target and zero velocity. Used by the headless bundle path so SVG/PNG fixtures don’t depend on integrator timing.

pub fn step(&mut self, now: Instant) -> bool

Step the animation forward to now. Returns true if settled.

Trait Implementations

impl Clone for Animation

fn clone(&self) -> Animation

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Animation

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

Formats the value using the given formatter.