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Tween

Tween<T>​

A generic struct that handles smooth transitions between values over time.

turbo::tween
pub struct Tween<T> {
    pub start: T,
    pub end: T,
    pub duration: usize,
    pub elapsed: usize,
    pub easing: Easing,
    pub start_tick: Option<usize>,
}

Create a new tween​

// Create a new tween starting at 0.0
let mut tween = Tween::new(0.0);

Set a target​

// Tween will transition from its current value to 100.0
tween.set(100.0);

Set duration​

// Tween will complete in 60 ticks
tween.set_duration(60);

Set easing​

// Use quadratic easing
tween.set_ease(Easing::EaseInQuad);

Get current value of tween​

// Get the current value of the tween
let current = tween.get();

Check if complete​

if tween.done() {
    // Tween has finished
}

Add to target​

// Add 10 to the end value
tween.add(10.0);

Complete Example​

Create a tween that moves across the screen horizontally.

turbo::init! {
    struct GameState {
        position: Tween<f32>,
    } = {
        Self {
            position: Tween::new(0.0)
                .duration(120)
                .ease(Easing::EaseInOutQuad)
                .set(220.0)
        }
    }
}

turbo::go! {
    let mut state = GameState::load();
    // Get the current value of the tween
    let val = state.position.get();
    // Draw a circle using that value
    circ!(x = val, y = 72, d=8, color = 0x32CD32ff);
    state.save();
}

Tween example showing smooth animation