jjyl_subsidy/utils/signature_pad.js

/*!
 * Signature Pad v3.0.0-beta.3 | https://github.com/szimek/signature_pad
 * (c) 2018 Szymon Nowak | Released under the MIT license
 */

(function (global, factory) {
    typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
    typeof define === 'function' && define.amd ? define(factory) :
    (global.SignaturePad = factory());
  }(this, (function () { 'use strict';
  
    var Point = (function () {
        function Point(x, y, time) {
            this.x = x;
            this.y = y;
            this.time = time || Date.now();
        }
        Point.prototype.distanceTo = function (start) {
            return Math.sqrt(Math.pow(this.x - start.x, 2) + Math.pow(this.y - start.y, 2));
        };
        Point.prototype.equals = function (other) {
            return this.x === other.x && this.y === other.y && this.time === other.time;
        };
        Point.prototype.velocityFrom = function (start) {
            return (this.time !== start.time) ? this.distanceTo(start) / (this.time - start.time) : 0;
        };
        return Point;
    }());
  
    var Bezier = (function () {
        function Bezier(startPoint, control2, control1, endPoint, startWidth, endWidth) {
            this.startPoint = startPoint;
            this.control2 = control2;
            this.control1 = control1;
            this.endPoint = endPoint;
            this.startWidth = startWidth;
            this.endWidth = endWidth;
        }
        Bezier.fromPoints = function (points, widths) {
            var c2 = this.calculateControlPoints(points[0], points[1], points[2]).c2;
            var c3 = this.calculateControlPoints(points[1], points[2], points[3]).c1;
            return new Bezier(points[1], c2, c3, points[2], widths.start, widths.end);
        };
        Bezier.calculateControlPoints = function (s1, s2, s3) {
            var dx1 = s1.x - s2.x;
            var dy1 = s1.y - s2.y;
            var dx2 = s2.x - s3.x;
            var dy2 = s2.y - s3.y;
            var m1 = { x: (s1.x + s2.x) / 2.0, y: (s1.y + s2.y) / 2.0 };
            var m2 = { x: (s2.x + s3.x) / 2.0, y: (s2.y + s3.y) / 2.0 };
            var l1 = Math.sqrt((dx1 * dx1) + (dy1 * dy1));
            var l2 = Math.sqrt((dx2 * dx2) + (dy2 * dy2));
            var dxm = (m1.x - m2.x);
            var dym = (m1.y - m2.y);
            var k = l2 / (l1 + l2);
            var cm = { x: m2.x + (dxm * k), y: m2.y + (dym * k) };
            var tx = s2.x - cm.x;
            var ty = s2.y - cm.y;
            return {
                c1: new Point(m1.x + tx, m1.y + ty),
                c2: new Point(m2.x + tx, m2.y + ty)
            };
        };
        Bezier.prototype.length = function () {
            var steps = 10;
            var length = 0;
            var px;
            var py;
            for (var i = 0; i <= steps; i += 1) {
                var t = i / steps;
                var cx = this.point(t, this.startPoint.x, this.control1.x, this.control2.x, this.endPoint.x);
                var cy = this.point(t, this.startPoint.y, this.control1.y, this.control2.y, this.endPoint.y);
                if (i > 0) {
                    var xdiff = cx - px;
                    var ydiff = cy - py;
                    length += Math.sqrt((xdiff * xdiff) + (ydiff * ydiff));
                }
                px = cx;
                py = cy;
            }
            return length;
        };
        Bezier.prototype.point = function (t, start, c1, c2, end) {
            return (start * (1.0 - t) * (1.0 - t) * (1.0 - t))
                + (3.0 * c1 * (1.0 - t) * (1.0 - t) * t)
                + (3.0 * c2 * (1.0 - t) * t * t)
                + (end * t * t * t);
        };
        return Bezier;
    }());
  
    function throttle(fn, wait) {
        if (wait === void 0) { wait = 250; }
        var previous = 0;
        var timeout = null;
        var result;
        var storedContext;
        var storedArgs;
        var later = function () {
            previous = Date.now();
            timeout = null;
            result = fn.apply(storedContext, storedArgs);
            if (!timeout) {
                storedContext = null;
                storedArgs = [];
            }
        };
        return function () {
            var args = [];
            for (var _i = 0; _i < arguments.length; _i++) {
                args[_i] = arguments[_i];
            }
            var now = Date.now();
            var remaining = wait - (now - previous);
            storedContext = this;
            storedArgs = args;
            if (remaining <= 0 || remaining > wait) {
                if (timeout) {
                    clearTimeout(timeout);
                    timeout = null;
                }
                previous = now;
                result = fn.apply(storedContext, storedArgs);
                if (!timeout) {
                    storedContext = null;
                    storedArgs = [];
                }
            }
            else if (!timeout) {
                timeout = setTimeout(later, remaining);
            }
            return result;
        };
    }
  
    var SignaturePad = (function () {
        function SignaturePad(canvas, options) {
            if (options === void 0) { options = {}; }
            var _this = this;
            this.canvas = canvas;
            this.options = options;
            this._handleTouchStart = function (event) {
                if (event.touches.length === 1) {
                    var touch = event.changedTouches[0];
                    _this._strokeBegin(touch);
                }
            };
            this._handleTouchMove = function (event) {
                var touch = event.touches[0];
                _this._strokeMoveUpdate(touch);
            };
            this._handleTouchEnd = function (event) {
                var wasCanvasTouched = event.target === _this.canvas;
                if (wasCanvasTouched) {
                    event.preventDefault();
                    var touch = event.changedTouches[0];
                    _this._strokeEnd(touch);
                }
            };
            this.velocityFilterWeight = options.velocityFilterWeight || 0.7;
            this.minWidth = options.minWidth || 0.5;
            this.maxWidth = options.maxWidth || 2.5;
            this.throttle = ('throttle' in options ? options.throttle : 16);
            this.minDistance = ('minDistance' in options ? options.minDistance : 5);
            if (this.throttle) {
                this._strokeMoveUpdate = throttle(SignaturePad.prototype._strokeUpdate, this.throttle);
            }
            else {
                this._strokeMoveUpdate = SignaturePad.prototype._strokeUpdate;
            }
            this.dotSize = options.dotSize || function () {
                return (this.minWidth + this.maxWidth) / 2;
            };
            this.penColor = options.penColor || 'black';
            this.backgroundColor = options.backgroundColor || 'rgba(0,0,0,0)';
            this.onBegin = options.onBegin;
            this.onEnd = options.onEnd;
            this._ctx = canvas.getContext('2d');
            this.clear();
        }
        SignaturePad.prototype.clear = function () {
            var ctx = this._ctx;
            var canvas = this.canvas;
            ctx.fillStyle = this.backgroundColor;
            ctx.clearRect(0, 0, canvas.width, canvas.height);
            ctx.fillRect(0, 0, canvas.width, canvas.height);
            this._data = [];
            this._reset();
            this._isEmpty = true;
        };
        SignaturePad.prototype.fromDataURL = function (dataUrl, options, callback) {
            var _this = this;
            if (options === void 0) { options = {}; }
            var image = new Image();
            var ratio = options.ratio || 1;
            var width = options.width || (this.canvas.width / ratio);
            var height = options.height || (this.canvas.height / ratio);
            this._reset();
            image.onload = function () {
                _this._ctx.drawImage(image, 0, 0, width, height);
                if (callback) {
                    callback();
                }
            };
            image.onerror = function (error) {
                if (callback) {
                    callback(error);
                }
            };
            image.src = dataUrl;
            this._isEmpty = false;
        };
        SignaturePad.prototype.toDataURL = function (type, encoderOptions) {
            if (type === void 0) { type = 'image/png'; }
            return this.canvas.toDataURL(type, encoderOptions);
        };
        SignaturePad.prototype.isEmpty = function () {
            return this._isEmpty;
        };
        SignaturePad.prototype.fromData = function (pointGroups) {
            var _this = this;
            this.clear();
            this._fromData(pointGroups, function (_a) {
                var color = _a.color, curve = _a.curve;
                return _this._drawCurve({ color: color, curve: curve });
            }, function (_a) {
                var color = _a.color, point = _a.point;
                return _this._drawDot({ color: color, point: point });
            });
            this._data = pointGroups;
        };
        SignaturePad.prototype.toData = function () {
            return this._data;
        };
        SignaturePad.prototype._strokeBegin = function (event) {
            var newPointGroup = {
                color: this.penColor,
                points: []
            };
            this._data.push(newPointGroup);
            this._reset();
            this._strokeUpdate(event);
            if (typeof this.onBegin === 'function') {
                this.onBegin(event);
            }
        };
        SignaturePad.prototype._strokeUpdate = function (event) {
            var x = event.x;
            var y = event.y;
            var point = this._createPoint(x, y);
            var lastPointGroup = this._data[this._data.length - 1];
            var lastPoints = lastPointGroup.points;
            var lastPoint = lastPoints.length > 0 && lastPoints[lastPoints.length - 1];
            var isLastPointTooClose = lastPoint ? point.distanceTo(lastPoint) <= this.minDistance : false;
            var color = lastPointGroup.color;
            if (!lastPoint || !(lastPoint && isLastPointTooClose)) {
                var curve = this._addPoint(point);
                if (!lastPoint) {
                    this._drawDot({ color: color, point: point });
                }
                else if (curve) {
                    this._drawCurve({ color: color, curve: curve });
                }
                lastPoints.push({
                    time: point.time,
                    x: point.x,
                    y: point.y
                });
            }
        };
        SignaturePad.prototype._strokeEnd = function (event) {
            this._strokeUpdate(event);
            if (typeof this.onEnd === 'function') {
                this.onEnd(event);
            }
        };
        SignaturePad.prototype._reset = function () {
            this._lastPoints = [];
            this._lastVelocity = 0;
            this._lastWidth = (this.minWidth + this.maxWidth) / 2;
            this._ctx.fillStyle = this.penColor;
        };
        SignaturePad.prototype._createPoint = function (x, y) {
            return new Point(x, y, new Date().getTime());
        };
        SignaturePad.prototype._addPoint = function (point) {
            var _lastPoints = this._lastPoints;
            _lastPoints.push(point);
            if (_lastPoints.length > 2) {
                if (_lastPoints.length === 3) {
                    _lastPoints.unshift(_lastPoints[0]);
                }
                var widths = this._calculateCurveWidths(_lastPoints[1], _lastPoints[2]);
                var curve = Bezier.fromPoints(_lastPoints, widths);
                _lastPoints.shift();
                return curve;
            }
            return null;
        };
        SignaturePad.prototype._calculateCurveWidths = function (startPoint, endPoint) {
            var velocity = (this.velocityFilterWeight * endPoint.velocityFrom(startPoint))
                + ((1 - this.velocityFilterWeight) * this._lastVelocity);
            var newWidth = this._strokeWidth(velocity);
            var widths = {
                end: newWidth,
                start: this._lastWidth
            };
            this._lastVelocity = velocity;
            this._lastWidth = newWidth;
            return widths;
        };
        SignaturePad.prototype._strokeWidth = function (velocity) {
            return Math.max(this.maxWidth / (velocity + 1), this.minWidth);
        };
        SignaturePad.prototype._drawCurveSegment = function (x, y, width) {
            var ctx = this._ctx;
            ctx.moveTo(x, y);
            ctx.arc(x, y, width, 0, 2 * Math.PI, false);
            this._isEmpty = false;
        };
        SignaturePad.prototype._drawCurve = function (_a) {
            var color = _a.color, curve = _a.curve;
            var ctx = this._ctx;
            var widthDelta = curve.endWidth - curve.startWidth;
            var drawSteps = Math.floor(curve.length()) * 2;
            ctx.beginPath();
            ctx.fillStyle = color;
            for (var i = 0; i < drawSteps; i += 1) {
                var t = i / drawSteps;
                var tt = t * t;
                var ttt = tt * t;
                var u = 1 - t;
                var uu = u * u;
                var uuu = uu * u;
                var x = uuu * curve.startPoint.x;
                x += 3 * uu * t * curve.control1.x;
                x += 3 * u * tt * curve.control2.x;
                x += ttt * curve.endPoint.x;
                var y = uuu * curve.startPoint.y;
                y += 3 * uu * t * curve.control1.y;
                y += 3 * u * tt * curve.control2.y;
                y += ttt * curve.endPoint.y;
                var width = curve.startWidth + (ttt * widthDelta);
                this._drawCurveSegment(x, y, width);
            }
            ctx.closePath();
            ctx.fill();
        };
        SignaturePad.prototype._drawDot = function (_a) {
            var color = _a.color, point = _a.point;
            var ctx = this._ctx;
            var width = 1;
            ctx.beginPath();
            this._drawCurveSegment(point.x, point.y, width);
            ctx.closePath();
            ctx.fillStyle = color;
            ctx.fill();
        };
        SignaturePad.prototype._fromData = function (pointGroups, drawCurve, drawDot) {
            for (var _i = 0, pointGroups_1 = pointGroups; _i < pointGroups_1.length; _i++) {
                var group = pointGroups_1[_i];
                var color = group.color, points = group.points;
                if (points.length > 1) {
                    for (var j = 0; j < points.length; j += 1) {
                        var basicPoint = points[j];
                        var point = new Point(basicPoint.x, basicPoint.y, basicPoint.time);
                        this.penColor = color;
                        if (j === 0) {
                            this._reset();
                        }
                        var curve = this._addPoint(point);
                        if (curve) {
                            drawCurve({ color: color, curve: curve });
                        }
                    }
                }
                else {
                    this._reset();
                    drawDot({
                        color: color,
                        point: points[0]
                    });
                }
            }
        };
        return SignaturePad;
    }());
  
    return SignaturePad;
  
  })));