src/extras/crosshair.js
function(opt_options) {
    this.canvas_ = document.createElement("canvas");
    opt_options = opt_options || {};
    this.direction_ = opt_options.direction || null;
  }
function(opt_options) {
    this.canvas_ = document.createElement("canvas");
    opt_options = opt_options || {};
    this.direction_ = opt_options.direction || null;
  }
Creates the crosshair

@constructor