Fabric JS Arrow

fabric.arrow.js

fabric.Arrow = fabric.util.createClass(fabric.Line, {

  type: 'Arrow',

  initialize: function(element, options) {
    options || (options = {});
    this.callSuper('initialize', element, options);
  },

  toObject: function() {
    return fabric.util.object.extend(this.callSuper('toObject'));
  },

  _render: function(ctx){
    this.callSuper('_render', ctx);

    // do not render if width/height are zeros or object is not visible
    if (this.width === 0 && this.height === 0 || !this.visible) return;

    ctx.save();

    var xDiff = this.x2 - this.x1;
    var yDiff = this.y2 - this.y1;
    var angle = Math.atan2(yDiff, xDiff);
    ctx.translate((this.x2 - this.x1) / 2, (this.y2 - this.y1) / 2);
    ctx.rotate(angle);
    ctx.beginPath();
    //move 10px in front of line to start the arrow so it does not have the square line end showing in front (0,0)
    ctx.moveTo(10,0);
    ctx.lineTo(-10, 10);
    ctx.lineTo(-10, -10);
    ctx.closePath();
    ctx.fillStyle = this.stroke;
    ctx.fill();

    ctx.restore();
  },

  clipTo: function(ctx) {
    this._render(ctx);
  }
});

fabric.Arrow.fromObject = function (object, callback) {
    callback && callback(new fabric.Arrow([object.x1, object.y1, object.x2, object.y2],object));
};

fabric.Arrow.async = true;

clipTo fails when you minify the code, instead use,

clipTo: function() {
var ctx = arguments[0];
this._render(ctx);
}