cocos2d-html5 point in polygon

helper.js

var H = Helper = {
  pointInPolyon: function (n, vertices, touch) {
        var i, j, c = false;
        for (i = 0, j = n - 1; i < n; j = i++) {
            if (((vertices[i].y > touch.y) != (vertices[j].y > touch.y)) &&
                (touch.x < (vertices[j].x - vertices[i].x) * (touch.y - vertices[i].y) / (vertices[j].y - vertices[i].y) + vertices[i].x )) {
                c = !c;
            }
        }
        return c;
    }
};

main.js

// Create sprite and vertices
var sprite1 = cc.Sprite.createWithSpriteFrameName('pyramid.png');
sprite1.setPosition(c.pp(200,200));
var vertices = [
    [0, 1],
    [0.5, 0],
    [1, 1]
];
sprite1.setRelativeVertices(vertices);

// Layer Touch event
onTouchBegan: function (touch) {
    var children = this.getChildren();
    children.forEach(function (child) {
        var touchPoint = touch.getLocation();
        var rect = child.getBoundingBox();

        if (cc.rectContainsPoint(rect, touchPoint)) {
            if (child.isTouchableAtPoint(touchPoint)) {
                child.setPosition(cc.p(H.random(320), H.random(480)));
                console.log('touch ' + child.toString() + ' ' + new Date());
                child.updateVertices();
            }
        }
    });
},

sprite_vertices.js

// Usage: set vertices like: [ [0,0], [0.5, 0.5], [1,0] ]
// Generate vertices: [ cc.p(0,0), cc.p(50,50), cc.p(100,0) ]
cc.Sprite.prototype.setRelativeVertices = function (vertices) {
    this._relativeVertices = vertices;
    this.updateVertices();
};

// Usage: call this to update vertices when the position is changed
cc.Sprite.prototype.updateVertices = function () {
    var vertices = this._relativeVertices;
    this._vertices = new Array(vertices.length);
    var rect = this.getBoundingBox();

    for (var i = 0; i < vertices.length; ++i) {
        var arr = vertices[i];
        var x = arr[0] * rect.width + rect.origin.x;
        var y = arr[1] * rect.height + rect.origin.y;

        this._vertices[i] = cc.p(x, y);
    }
};

// Usage: check whether touch point in polygon
cc.Sprite.prototype.isTouchableAtPoint = function (touch) {
    if (!this._vertices) { throw "no vertices"; }
    return H.pointInPolyon(this._vertices.length, this._vertices, touch);
};

Thanks for sharing this, much appreciated!