mirror of
https://github.com/snipe/snipe-it.git
synced 2024-11-15 18:14:09 -08:00
390 lines
12 KiB
JavaScript
Executable file
390 lines
12 KiB
JavaScript
Executable file
(function (root, factory) {
|
|
if (typeof define === 'function' && define.amd) {
|
|
// AMD. Register as an anonymous module unless amdModuleId is set
|
|
define([], function () {
|
|
return (root['SignaturePad'] = factory());
|
|
});
|
|
} else if (typeof exports === 'object') {
|
|
// Node. Does not work with strict CommonJS, but
|
|
// only CommonJS-like environments that support module.exports,
|
|
// like Node.
|
|
module.exports = factory();
|
|
} else {
|
|
root['SignaturePad'] = factory();
|
|
}
|
|
}(this, function () {
|
|
|
|
/*!
|
|
* Signature Pad v1.5.3
|
|
* https://github.com/szimek/signature_pad
|
|
*
|
|
* Copyright 2016 Szymon Nowak
|
|
* Released under the MIT license
|
|
*
|
|
* The main idea and some parts of the code (e.g. drawing variable width Bézier curve) are taken from:
|
|
* http://corner.squareup.com/2012/07/smoother-signatures.html
|
|
*
|
|
* Implementation of interpolation using cubic Bézier curves is taken from:
|
|
* http://benknowscode.wordpress.com/2012/09/14/path-interpolation-using-cubic-bezier-and-control-point-estimation-in-javascript
|
|
*
|
|
* Algorithm for approximated length of a Bézier curve is taken from:
|
|
* http://www.lemoda.net/maths/bezier-length/index.html
|
|
*
|
|
*/
|
|
var SignaturePad = (function (document) {
|
|
"use strict";
|
|
|
|
var SignaturePad = function (canvas, options) {
|
|
var self = this,
|
|
opts = options || {};
|
|
|
|
this.velocityFilterWeight = opts.velocityFilterWeight || 0.7;
|
|
this.minWidth = opts.minWidth || 0.5;
|
|
this.maxWidth = opts.maxWidth || 2.5;
|
|
this.dotSize = opts.dotSize || function () {
|
|
return (this.minWidth + this.maxWidth) / 2;
|
|
};
|
|
this.penColor = opts.penColor || "black";
|
|
this.backgroundColor = opts.backgroundColor || "rgba(0,0,0,0)";
|
|
this.onEnd = opts.onEnd;
|
|
this.onBegin = opts.onBegin;
|
|
|
|
this._canvas = canvas;
|
|
this._ctx = canvas.getContext("2d");
|
|
this.clear();
|
|
|
|
// we need add these inline so they are available to unbind while still having
|
|
// access to 'self' we could use _.bind but it's not worth adding a dependency
|
|
this._handleMouseDown = function (event) {
|
|
if (event.which === 1) {
|
|
self._mouseButtonDown = true;
|
|
self._strokeBegin(event);
|
|
}
|
|
};
|
|
|
|
this._handleMouseMove = function (event) {
|
|
if (self._mouseButtonDown) {
|
|
self._strokeUpdate(event);
|
|
}
|
|
};
|
|
|
|
this._handleMouseUp = function (event) {
|
|
if (event.which === 1 && self._mouseButtonDown) {
|
|
self._mouseButtonDown = false;
|
|
self._strokeEnd(event);
|
|
}
|
|
};
|
|
|
|
this._handleTouchStart = function (event) {
|
|
if (event.targetTouches.length == 1) {
|
|
var touch = event.changedTouches[0];
|
|
self._strokeBegin(touch);
|
|
}
|
|
};
|
|
|
|
this._handleTouchMove = function (event) {
|
|
// Prevent scrolling.
|
|
event.preventDefault();
|
|
|
|
var touch = event.targetTouches[0];
|
|
self._strokeUpdate(touch);
|
|
};
|
|
|
|
this._handleTouchEnd = function (event) {
|
|
var wasCanvasTouched = event.target === self._canvas;
|
|
if (wasCanvasTouched) {
|
|
event.preventDefault();
|
|
self._strokeEnd(event);
|
|
}
|
|
};
|
|
|
|
this._handleMouseEvents();
|
|
this._handleTouchEvents();
|
|
};
|
|
|
|
SignaturePad.prototype.clear = function () {
|
|
var ctx = this._ctx,
|
|
canvas = this._canvas;
|
|
|
|
ctx.fillStyle = this.backgroundColor;
|
|
ctx.clearRect(0, 0, canvas.width, canvas.height);
|
|
ctx.fillRect(0, 0, canvas.width, canvas.height);
|
|
this._reset();
|
|
};
|
|
|
|
SignaturePad.prototype.toDataURL = function (imageType, quality) {
|
|
var canvas = this._canvas;
|
|
return canvas.toDataURL.apply(canvas, arguments);
|
|
};
|
|
|
|
SignaturePad.prototype.fromDataURL = function (dataUrl) {
|
|
var self = this,
|
|
image = new Image(),
|
|
ratio = window.devicePixelRatio || 1,
|
|
width = this._canvas.width / ratio,
|
|
height = this._canvas.height / ratio;
|
|
|
|
this._reset();
|
|
image.src = dataUrl;
|
|
image.onload = function () {
|
|
self._ctx.drawImage(image, 0, 0, width, height);
|
|
};
|
|
this._isEmpty = false;
|
|
};
|
|
|
|
SignaturePad.prototype._strokeUpdate = function (event) {
|
|
var point = this._createPoint(event);
|
|
this._addPoint(point);
|
|
};
|
|
|
|
SignaturePad.prototype._strokeBegin = function (event) {
|
|
this._reset();
|
|
this._strokeUpdate(event);
|
|
if (typeof this.onBegin === 'function') {
|
|
this.onBegin(event);
|
|
}
|
|
};
|
|
|
|
SignaturePad.prototype._strokeDraw = function (point) {
|
|
var ctx = this._ctx,
|
|
dotSize = typeof(this.dotSize) === 'function' ? this.dotSize() : this.dotSize;
|
|
|
|
ctx.beginPath();
|
|
this._drawPoint(point.x, point.y, dotSize);
|
|
ctx.closePath();
|
|
ctx.fill();
|
|
};
|
|
|
|
SignaturePad.prototype._strokeEnd = function (event) {
|
|
var canDrawCurve = this.points.length > 2,
|
|
point = this.points[0];
|
|
|
|
if (!canDrawCurve && point) {
|
|
this._strokeDraw(point);
|
|
}
|
|
if (typeof this.onEnd === 'function') {
|
|
this.onEnd(event);
|
|
}
|
|
};
|
|
|
|
SignaturePad.prototype._handleMouseEvents = function () {
|
|
this._mouseButtonDown = false;
|
|
|
|
this._canvas.addEventListener("mousedown", this._handleMouseDown);
|
|
this._canvas.addEventListener("mousemove", this._handleMouseMove);
|
|
document.addEventListener("mouseup", this._handleMouseUp);
|
|
};
|
|
|
|
SignaturePad.prototype._handleTouchEvents = function () {
|
|
// Pass touch events to canvas element on mobile IE11 and Edge.
|
|
this._canvas.style.msTouchAction = 'none';
|
|
this._canvas.style.touchAction = 'none';
|
|
|
|
this._canvas.addEventListener("touchstart", this._handleTouchStart);
|
|
this._canvas.addEventListener("touchmove", this._handleTouchMove);
|
|
this._canvas.addEventListener("touchend", this._handleTouchEnd);
|
|
};
|
|
|
|
SignaturePad.prototype.on = function () {
|
|
this._handleMouseEvents();
|
|
this._handleTouchEvents();
|
|
};
|
|
|
|
SignaturePad.prototype.off = function () {
|
|
this._canvas.removeEventListener("mousedown", this._handleMouseDown);
|
|
this._canvas.removeEventListener("mousemove", this._handleMouseMove);
|
|
document.removeEventListener("mouseup", this._handleMouseUp);
|
|
|
|
this._canvas.removeEventListener("touchstart", this._handleTouchStart);
|
|
this._canvas.removeEventListener("touchmove", this._handleTouchMove);
|
|
this._canvas.removeEventListener("touchend", this._handleTouchEnd);
|
|
};
|
|
|
|
SignaturePad.prototype.isEmpty = function () {
|
|
return this._isEmpty;
|
|
};
|
|
|
|
SignaturePad.prototype._reset = function () {
|
|
this.points = [];
|
|
this._lastVelocity = 0;
|
|
this._lastWidth = (this.minWidth + this.maxWidth) / 2;
|
|
this._isEmpty = true;
|
|
this._ctx.fillStyle = this.penColor;
|
|
};
|
|
|
|
SignaturePad.prototype._createPoint = function (event) {
|
|
var rect = this._canvas.getBoundingClientRect();
|
|
return new Point(
|
|
event.clientX - rect.left,
|
|
event.clientY - rect.top
|
|
);
|
|
};
|
|
|
|
SignaturePad.prototype._addPoint = function (point) {
|
|
var points = this.points,
|
|
c2, c3,
|
|
curve, tmp;
|
|
|
|
points.push(point);
|
|
|
|
if (points.length > 2) {
|
|
// To reduce the initial lag make it work with 3 points
|
|
// by copying the first point to the beginning.
|
|
if (points.length === 3) points.unshift(points[0]);
|
|
|
|
tmp = this._calculateCurveControlPoints(points[0], points[1], points[2]);
|
|
c2 = tmp.c2;
|
|
tmp = this._calculateCurveControlPoints(points[1], points[2], points[3]);
|
|
c3 = tmp.c1;
|
|
curve = new Bezier(points[1], c2, c3, points[2]);
|
|
this._addCurve(curve);
|
|
|
|
// Remove the first element from the list,
|
|
// so that we always have no more than 4 points in points array.
|
|
points.shift();
|
|
}
|
|
};
|
|
|
|
SignaturePad.prototype._calculateCurveControlPoints = function (s1, s2, s3) {
|
|
var dx1 = s1.x - s2.x, dy1 = s1.y - s2.y,
|
|
dx2 = s2.x - s3.x, dy2 = s2.y - s3.y,
|
|
|
|
m1 = {x: (s1.x + s2.x) / 2.0, y: (s1.y + s2.y) / 2.0},
|
|
m2 = {x: (s2.x + s3.x) / 2.0, y: (s2.y + s3.y) / 2.0},
|
|
|
|
l1 = Math.sqrt(dx1*dx1 + dy1*dy1),
|
|
l2 = Math.sqrt(dx2*dx2 + dy2*dy2),
|
|
|
|
dxm = (m1.x - m2.x),
|
|
dym = (m1.y - m2.y),
|
|
|
|
k = l2 / (l1 + l2),
|
|
cm = {x: m2.x + dxm*k, y: m2.y + dym*k},
|
|
|
|
tx = s2.x - cm.x,
|
|
ty = s2.y - cm.y;
|
|
|
|
return {
|
|
c1: new Point(m1.x + tx, m1.y + ty),
|
|
c2: new Point(m2.x + tx, m2.y + ty)
|
|
};
|
|
};
|
|
|
|
SignaturePad.prototype._addCurve = function (curve) {
|
|
var startPoint = curve.startPoint,
|
|
endPoint = curve.endPoint,
|
|
velocity, newWidth;
|
|
|
|
velocity = endPoint.velocityFrom(startPoint);
|
|
velocity = this.velocityFilterWeight * velocity
|
|
+ (1 - this.velocityFilterWeight) * this._lastVelocity;
|
|
|
|
newWidth = this._strokeWidth(velocity);
|
|
this._drawCurve(curve, this._lastWidth, newWidth);
|
|
|
|
this._lastVelocity = velocity;
|
|
this._lastWidth = newWidth;
|
|
};
|
|
|
|
SignaturePad.prototype._drawPoint = function (x, y, size) {
|
|
var ctx = this._ctx;
|
|
|
|
ctx.moveTo(x, y);
|
|
ctx.arc(x, y, size, 0, 2 * Math.PI, false);
|
|
this._isEmpty = false;
|
|
};
|
|
|
|
SignaturePad.prototype._drawCurve = function (curve, startWidth, endWidth) {
|
|
var ctx = this._ctx,
|
|
widthDelta = endWidth - startWidth,
|
|
drawSteps, width, i, t, tt, ttt, u, uu, uuu, x, y;
|
|
|
|
drawSteps = Math.floor(curve.length());
|
|
ctx.beginPath();
|
|
for (i = 0; i < drawSteps; i++) {
|
|
// Calculate the Bezier (x, y) coordinate for this step.
|
|
t = i / drawSteps;
|
|
tt = t * t;
|
|
ttt = tt * t;
|
|
u = 1 - t;
|
|
uu = u * u;
|
|
uuu = uu * u;
|
|
|
|
x = uuu * curve.startPoint.x;
|
|
x += 3 * uu * t * curve.control1.x;
|
|
x += 3 * u * tt * curve.control2.x;
|
|
x += ttt * curve.endPoint.x;
|
|
|
|
y = uuu * curve.startPoint.y;
|
|
y += 3 * uu * t * curve.control1.y;
|
|
y += 3 * u * tt * curve.control2.y;
|
|
y += ttt * curve.endPoint.y;
|
|
|
|
width = startWidth + ttt * widthDelta;
|
|
this._drawPoint(x, y, width);
|
|
}
|
|
ctx.closePath();
|
|
ctx.fill();
|
|
};
|
|
|
|
SignaturePad.prototype._strokeWidth = function (velocity) {
|
|
return Math.max(this.maxWidth / (velocity + 1), this.minWidth);
|
|
};
|
|
|
|
|
|
var Point = function (x, y, time) {
|
|
this.x = x;
|
|
this.y = y;
|
|
this.time = time || new Date().getTime();
|
|
};
|
|
|
|
Point.prototype.velocityFrom = function (start) {
|
|
return (this.time !== start.time) ? this.distanceTo(start) / (this.time - start.time) : 1;
|
|
};
|
|
|
|
Point.prototype.distanceTo = function (start) {
|
|
return Math.sqrt(Math.pow(this.x - start.x, 2) + Math.pow(this.y - start.y, 2));
|
|
};
|
|
|
|
var Bezier = function (startPoint, control1, control2, endPoint) {
|
|
this.startPoint = startPoint;
|
|
this.control1 = control1;
|
|
this.control2 = control2;
|
|
this.endPoint = endPoint;
|
|
};
|
|
|
|
// Returns approximated length.
|
|
Bezier.prototype.length = function () {
|
|
var steps = 10,
|
|
length = 0,
|
|
i, t, cx, cy, px, py, xdiff, ydiff;
|
|
|
|
for (i = 0; i <= steps; i++) {
|
|
t = i / steps;
|
|
cx = this._point(t, this.startPoint.x, this.control1.x, this.control2.x, this.endPoint.x);
|
|
cy = this._point(t, this.startPoint.y, this.control1.y, this.control2.y, this.endPoint.y);
|
|
if (i > 0) {
|
|
xdiff = cx - px;
|
|
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 SignaturePad;
|
|
})(document);
|
|
|
|
return SignaturePad;
|
|
|
|
}));
|