core-animation

Rust bindings for macOS Core Animation with ergonomic builder APIs.

Builders

Builder	Purpose
WindowBuilder	Layer-backed windows with background, border, transparency
CALayerBuilder	Base layers with bounds, position, sublayers
CAShapeLayerBuilder	Vector shapes with path, fill, stroke, shadows
CATextLayerBuilder	Text rendering layers
CAEmitterLayerBuilder	Particle systems with closure-based cell configuration
PointBurstBuilder	Convenience API for radial particle bursts
CABasicAnimationBuilder	Standalone GPU-accelerated animations

Quick Start

use core_animation::prelude::*;

let window = WindowBuilder::new()
    .title("Demo")
    .size(400.0, 400.0)
    .centered()
    .background_color(Color::rgb(0.1, 0.1, 0.15))
    .build();

let circle = CAShapeLayerBuilder::new()
    .circle(80.0)
    .position(CGPoint::new(200.0, 200.0))
    .fill_color(Color::CYAN)
    .animate("pulse", KeyPath::TransformScale, |a| {
        a.values(0.85, 1.15)
            .duration(1.seconds())
            .easing(Easing::InOut)
            .autoreverses()
            .repeat(Repeat::Forever)
    })
    .build();

window.container().add_sublayer(&circle);
window.show_for(10.seconds());

Animations

All layer builders support .animate() for GPU-accelerated animations:

.animate("name", KeyPath::TransformScale, |a| {
    a.values(0.8, 1.2)              // from/to values
        .duration(500.millis())      // timing
        .easing(Easing::InOut)       // curve
        .autoreverses()              // ping-pong
        .repeat(Repeat::Forever)     // loop
        .phase_offset(0.5)           // stagger multiple animations
})

Animatable properties: TransformScale, TransformRotation, Opacity, ShadowRadius, ShadowOpacity, Custom("propertyName")

Easing curves: Linear, In, Out, InOut

Particle Systems

use std::f64::consts::PI;

let emitter = CAEmitterLayerBuilder::new()
    .position(320.0, 240.0)
    .shape(EmitterShape::Point)
    .particle(|p| {
        p.birth_rate(100.0)
            .lifetime(5.0)
            .velocity(80.0)
            .emission_range(PI * 2.0)
            .color(Color::CYAN)
            .image(ParticleImage::soft_glow(64))
    })
    .build();

Or use the convenience builder:

let burst = PointBurstBuilder::new(320.0, 240.0)
    .velocity(100.0)
    .color(Color::PINK)
    .build();

Particle images: soft_glow, circle, star, spark

Examples

cargo run --example window_builder

See examples/README.md for all examples with screenshots.

Platform

macOS only.

License

Licensed under either of Apache License, Version 2.0 or MIT license at your option.