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API

Every export of @sweberdev/lagrangian and @sweberdev/lagrangian-react.

@sweberdev/lagrangian

Export	Signature
`animate`	`(targets, props, { duration?, bounce?, stiffness?, damping?, mass?, velocity?, delay?, stagger? }) => Animation`
`set`	`(targets, props) => void`: jump without animation
`getValue`	`(element, prop) => PhysicsValue`
`draggable`	`(element, { axis?, bounds?, rubberband?, inertia?, deceleration?, snap?, spring?, onStart?, onMove?, onEnd? }) => Draggable`
`value`	`(initial) => PhysicsValue`
`PhysicsValue`	`get()`, `velocity`, `animating`, `set(x)`, `jump(x)`, `to(target, spring?)`, `throw(decay?)`, `start(motion)`, `stop()`, `on(listener)`
`spring`	`(from, to, velocity?, options?) => Motion`
`decay`	`(from, { velocity?, deceleration?, min?, max?, snap?, bounce?, restDelta? }) => Motion`
`springParams`, `dampingRatio`	resolve `duration`/`bounce` into stiffness, damping, mass
`settleTime`, `restValue`	`(motion) => number`
`projectRest`, `timeConstant`, `nearest`	throw maths
`rubberband`, `rubberClamp`	iOS-style overscroll
`VelocityTracker`	`add(timeMs, value)`, `velocity(timeMs?)`, `reset()`
`World`, `world`	see The world
`rk4`, `system`	see Equations of motion
`loop`	`add(task)`, `manual(on)`, `step(ms)`, `size`: the shared frame loop
`reducedMotion`, `setReducedMotion`	see Reduced motion

targets is an element, a selector or a list of elements. An Animation has finished: Promise<boolean> and stop(). A Motion is (seconds) => { value, velocity, done }.

@sweberdev/lagrangian-react

Export	Signature
`useSpringProps`	`(props, options?) => RefObject`
`useSpring`	`(target, options?) => PhysicsValue`
`useValue`	`(value) => number`
`usePhysicsValue`	`(initial?) => PhysicsValue`
`useDraggable`	`(options?) => [ref, Draggable \| null]`
`useWorld`	`(options?) => [ref, World]`
`useBody`	`(world, options) => [ref, Body \| null]`

Testing

loop.manual(true) stops using requestAnimationFrame; loop.step(ms) then advances every animation and world by hand.