export var ACCURACY = 1e-4;
var cubicBezierFactor = (c1, c2) => [0, 3 * c1, 3 * c2 - 6 * c1, 3 * c1 - 3 * c2 + 1];
var evaluatePolynomial = (params, animationElapsedTime) => params.map((param, i) => param * animationElapsedTime ** i).reduce((pre, curr) => pre + curr);
var cubicBezier = (c1, c2) => animationElapsedTime => {
var params = cubicBezierFactor(c1, c2);
return evaluatePolynomial(params, animationElapsedTime);
};
var derivativeCubicBezier = (c1, c2) => animationElapsedTime => {
var params = cubicBezierFactor(c1, c2);
var newParams = [...params.map((param, i) => param * i).slice(1), 0];
return evaluatePolynomial(newParams, animationElapsedTime);
};
var parseCubicBezier = easing => {
var _easingParts$;
var easingParts = easing.split('(');
if (easingParts.length !== 2 || easingParts[0] !== 'cubic-bezier') {
return null;
}
var numbers = (_easingParts$ = easingParts[1]) === null || _easingParts$ === void 0 || (_easingParts$ = _easingParts$.split(')')[0]) === null || _easingParts$ === void 0 ? void 0 : _easingParts$.split(',');
if (numbers == null || numbers.length !== 4) {
return null;
}
var coords = numbers.map(x => parseFloat(x));
return [coords[0], coords[1], coords[2], coords[3]];
};
var getBezierCoordinates = function getBezierCoordinates() {
for (var _len = arguments.length, args = new Array(_len), _key = 0; _key < _len; _key++) {
args[_key] = arguments[_key];
}
if (args.length === 1) {
switch (args[0]) {
case 'linear':
return [0.0, 0.0, 1.0, 1.0];
case 'ease':
return [0.25, 0.1, 0.25, 1.0];
case 'ease-in':
return [0.42, 0.0, 1.0, 1.0];
case 'ease-out':
return [0.42, 0.0, 0.58, 1.0];
case 'ease-in-out':
return [0.0, 0.0, 0.58, 1.0];
default:
{
var easing = parseCubicBezier(args[0]);
if (easing) {
return easing;
}
}
}
}
if (args.length === 4) {
return args;
}
// Fallback for invalid inputs. The previous implementation was buggy and would lead to NaN.
// Returning linear easing is a safe default.
return [0.0, 0.0, 1.0, 1.0];
};
var createBezierEasing = (x1, y1, x2, y2) => {
var curveX = cubicBezier(x1, x2);
var curveY = cubicBezier(y1, y2);
var derCurveX = derivativeCubicBezier(x1, x2);
var rangeValue = value => {
if (value > 1) {
return 1;
}
if (value < 0) {
return 0;
}
return value;
};
var bezier = _animationElapsedTime => {
var animationElapsedTime = _animationElapsedTime > 1 ? 1 : _animationElapsedTime;
var x = animationElapsedTime;
for (var i = 0; i < 8; ++i) {
var evalT = curveX(x) - animationElapsedTime;
var derVal = derCurveX(x);
if (Math.abs(evalT - animationElapsedTime) < ACCURACY || derVal < ACCURACY) {
return curveY(x);
}
x = rangeValue(x - evalT / derVal);
}
return curveY(x);
};
bezier.isStepper = false;
return bezier;
};
// calculate cubic-bezier using Newton's method
export var configBezier = function configBezier() {
return createBezierEasing(...getBezierCoordinates(...arguments));
};
/**
* Creates a performance-optimized, progress-based spring easing function.
* It pre-calculates ("bakes") spring physics frames upfront based on a fixed duration,
* then returns a pure, lightweight function mapping progress (0 to 1) to the animated position.
* This approach is ideal for low-power devices because it removes heavy physics math from the frame loop.
*/
export var createSpringEasing = function createSpringEasing() {
var config = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : {};
var _config$stiff = config.stiff,
stiff = _config$stiff === void 0 ? 100 : _config$stiff,
_config$damping = config.damping,
damping = _config$damping === void 0 ? 8 : _config$damping,
_config$dt = config.dt,
dt = _config$dt === void 0 ? 16.67 : _config$dt;
var destX = 1;
var positions = [0];
var currX = 0;
var currV = 0;
// Safety valve to prevent accidental infinite loops if physics config is extreme
var maxIterations = 10000;
var iterations = 0;
// 1. Run the simulation until the spring completely stops moving
while (iterations < maxIterations) {
var FSpring = -(currX - destX) * stiff;
var FDamping = currV * damping;
currV += (FSpring - FDamping) * dt / 1000;
currX += currV * dt / 1000;
positions.push(currX);
// Stop only when position is essentially at 1.0 AND bounce velocity has died down
if (Math.abs(currX - destX) < ACCURACY && Math.abs(currV) < ACCURACY) {
break;
}
iterations++;
}
// Force the absolute final element to be exactly 1.0 for a perfect finish
positions[positions.length - 1] = destX;
var maxIndex = positions.length - 1;
// 2. The ultra-smooth runtime function mapping your 0..1 progress
return t => {
var _positions$index, _positions, _positions$index2;
if (t <= 0) return 0;
if (t >= 1) return destX;
// Scale t (0..1) proportionally across our entire pre-calculated array
var exactFrame = t * maxIndex;
var index = Math.floor(exactFrame);
var fraction = exactFrame - index;
// Blend between the two closest frames
return ((_positions$index = positions[index]) !== null && _positions$index !== void 0 ? _positions$index : 0) + (((_positions = positions[index + 1]) !== null && _positions !== void 0 ? _positions : 0) - ((_positions$index2 = positions[index]) !== null && _positions$index2 !== void 0 ? _positions$index2 : 0)) * fraction;
};
};
/**
* @inline
*/
export var createEasingFunction = easing => {
if (typeof easing === 'string') {
switch (easing) {
case 'ease':
case 'ease-in-out':
case 'ease-out':
case 'ease-in':
case 'linear':
return configBezier(easing);
case 'spring':
return createSpringEasing();
default:
if (easing.split('(')[0] === 'cubic-bezier') {
return configBezier(easing);
}
}
}
if (typeof easing === 'function') {
return easing;
}
return null;
};