/** * https://github.com/gre/bezier-easing * BezierEasing - use bezier curve for transition easing function * by Gaëtan Renaudeau 2014 - 2015 – MIT License * * https://github.com/manubb/Leaflet.PixiOverlay */ (function(f) { if (typeof exports === 'object' && typeof module !== 'undefined') { module.exports = f(); } else if (typeof define === 'function' && define.amd) { define([], f); } else { var g; if (typeof window !== 'undefined') { g = window; } else if (typeof global !== 'undefined') { g = global; } else if (typeof self !== 'undefined') { g = self; } else { g = this; } g.BezierEasing = f(); } })(function() { var define, module, exports; return (function() { function r(e, n, t) { function o(i, f) { if (!n[i]) { if (!e[i]) { var c = 'function' == typeof require && require; if (!f && c) return c(i, !0); if (u) return u(i, !0); var a = new Error("Cannot find module '" + i + "'"); throw ((a.code = 'MODULE_NOT_FOUND'), a); } var p = (n[i] = { exports: {} }); e[i][0].call( p.exports, function(r) { var n = e[i][1][r]; return o(n || r); }, p, p.exports, r, e, n, t ); } return n[i].exports; } for (var u = 'function' == typeof require && require, i = 0; i < t.length; i++) o(t[i]); return o; } return r; })()( { 1: [ function(require, module, exports) { /** * https://github.com/gre/bezier-easing * BezierEasing - use bezier curve for transition easing function * by Gaëtan Renaudeau 2014 - 2015 – MIT License */ // These values are established by empiricism with tests (tradeoff: performance VS precision) var NEWTON_ITERATIONS = 4; var NEWTON_MIN_SLOPE = 0.001; var SUBDIVISION_PRECISION = 0.0000001; var SUBDIVISION_MAX_ITERATIONS = 10; var kSplineTableSize = 11; var kSampleStepSize = 1.0 / (kSplineTableSize - 1.0); var float32ArraySupported = typeof Float32Array === 'function'; function A(aA1, aA2) { return 1.0 - 3.0 * aA2 + 3.0 * aA1; } function B(aA1, aA2) { return 3.0 * aA2 - 6.0 * aA1; } function C(aA1) { return 3.0 * aA1; } // Returns x(t) given t, x1, and x2, or y(t) given t, y1, and y2. function calcBezier(aT, aA1, aA2) { return ((A(aA1, aA2) * aT + B(aA1, aA2)) * aT + C(aA1)) * aT; } // Returns dx/dt given t, x1, and x2, or dy/dt given t, y1, and y2. function getSlope(aT, aA1, aA2) { return 3.0 * A(aA1, aA2) * aT * aT + 2.0 * B(aA1, aA2) * aT + C(aA1); } function binarySubdivide(aX, aA, aB, mX1, mX2) { var currentX, currentT, i = 0; do { currentT = aA + (aB - aA) / 2.0; currentX = calcBezier(currentT, mX1, mX2) - aX; if (currentX > 0.0) { aB = currentT; } else { aA = currentT; } } while (Math.abs(currentX) > SUBDIVISION_PRECISION && ++i < SUBDIVISION_MAX_ITERATIONS); return currentT; } function newtonRaphsonIterate(aX, aGuessT, mX1, mX2) { for (var i = 0; i < NEWTON_ITERATIONS; ++i) { var currentSlope = getSlope(aGuessT, mX1, mX2); if (currentSlope === 0.0) { return aGuessT; } var currentX = calcBezier(aGuessT, mX1, mX2) - aX; aGuessT -= currentX / currentSlope; } return aGuessT; } function LinearEasing(x) { return x; } module.exports = function bezier(mX1, mY1, mX2, mY2) { if (!(0 <= mX1 && mX1 <= 1 && 0 <= mX2 && mX2 <= 1)) { throw new Error('bezier x values must be in [0, 1] range'); } if (mX1 === mY1 && mX2 === mY2) { return LinearEasing; } // Precompute samples table var sampleValues = float32ArraySupported ? new Float32Array(kSplineTableSize) : new Array(kSplineTableSize); for (var i = 0; i < kSplineTableSize; ++i) { sampleValues[i] = calcBezier(i * kSampleStepSize, mX1, mX2); } function getTForX(aX) { var intervalStart = 0.0; var currentSample = 1; var lastSample = kSplineTableSize - 1; for (; currentSample !== lastSample && sampleValues[currentSample] <= aX; ++currentSample) { intervalStart += kSampleStepSize; } --currentSample; // Interpolate to provide an initial guess for t var dist = (aX - sampleValues[currentSample]) / (sampleValues[currentSample + 1] - sampleValues[currentSample]); var guessForT = intervalStart + dist * kSampleStepSize; var initialSlope = getSlope(guessForT, mX1, mX2); if (initialSlope >= NEWTON_MIN_SLOPE) { return newtonRaphsonIterate(aX, guessForT, mX1, mX2); } else if (initialSlope === 0.0) { return guessForT; } else { return binarySubdivide(aX, intervalStart, intervalStart + kSampleStepSize, mX1, mX2); } } return function BezierEasing(x) { // Because JavaScript number are imprecise, we should guarantee the extremes are right. if (x === 0) { return 0; } if (x === 1) { return 1; } return calcBezier(getTForX(x), mY1, mY2); }; }; }, {} ] }, {}, [1] )(1); });