konva/src/shapes/RegularPolygon.js

///////////////////////////////////////////////////////////////////////
//  RegularPolygon
///////////////////////////////////////////////////////////////////////
/**
 * RegularPolygon constructor.  Examples include triangles, squares, pentagons, hexagons, etc.
 * @constructor
 * @augments Kinetic.Shape
 * @param {Object} config
 */
Kinetic.RegularPolygon = function(config) {
    this._initRegularPolygon(config);
};

Kinetic.RegularPolygon.prototype = {
    _initRegularPolygon: function(config) {
        this.setDefaultAttrs({
            radius: 0,
            sides: 0
        });

        this.shapeType = "RegularPolygon";
        config.drawFunc = this.drawFunc;
        // call super constructor
        Kinetic.Shape.call(this, config);
    },
    drawFunc: function(context) {
        context.beginPath();
        context.moveTo(0, 0 - this.attrs.radius);

        for(var n = 1; n < this.attrs.sides; n++) {
            var x = this.attrs.radius * Math.sin(n * 2 * Math.PI / this.attrs.sides);
            var y = -1 * this.attrs.radius * Math.cos(n * 2 * Math.PI / this.attrs.sides);
            context.lineTo(x, y);
        }
        context.closePath();
        this.fill(context);
        this.stroke(context);
    }
};
Kinetic.Global.extend(Kinetic.RegularPolygon, Kinetic.Shape);

// add getters setters
Kinetic.Node.addGettersSetters(Kinetic.RegularPolygon, ['radius', 'sides']);

/**
 * set radius
 * @name setRadius
 * @methodOf Kinetic.RegularPolygon.prototype
 * @param {Number} radius
 */

/**
 * set number of sides
 * @name setSides
 * @methodOf Kinetic.RegularPolygon.prototype
 * @param {int} sides
 */
/**
 * get radius
 * @name getRadius
 * @methodOf Kinetic.RegularPolygon.prototype
 */

/**
 * get number of sides
 * @name getSides
 * @methodOf Kinetic.RegularPolygon.prototype
 */