README.md

sprung

Sprung is an easy-to-consume Curve that uses real physics equations to drive your animations.

Easy to consume

AnimatedContainer(
  /// Critically damped by default
  curve: Sprung(),
  /// ...
),

AnimatedContainer(
  /// Easily adjust damping value
  curve: Sprung(16),
  /// ...
),

AnimatedContainer(
  /// Build a custom spring
  curve: Sprung(
    damping: 20,
    stiffness: 180,
    mass: 1.0,
  ),
  /// ...
),

Sprung has three opinionated curves, Sprung.underDamped, Sprung.criticallyDamped, and Sprung.overDamped.

AnimatedContainer(
  curve: Sprung.underDamped,
  /// ...
),

Based on Physics

Using Flutter's physics engine which leverages Newton's Second Law of Motion, Hooke's Law, and velocity based damping, we implement the following equation to create realistic spring animations.

Believable motion

Reliable accuracy

Sprung exceeds Flutter specifications for curves by guaranteeing an error less than 1e-6. This amounts to a 0.0019px jitter at the beginning or end of a 1920px move.