lib/toxi/physics2d/constraints/AngularConstraint.js
function(theta_p,theta){
        if(arguments.length > 1){
            this.theta = theta;
            this.rootPos = new Vec2D(theta_p);
        } else {
            this.rootPos = new Vec2D();
            this.theta = theta_p;
        }
        //due to lack-of int/float types, no support of theta in degrees
    }
function(theta_p,theta){
        if(arguments.length > 1){
            this.theta = theta;
            this.rootPos = new Vec2D(theta_p);
        } else {
            this.rootPos = new Vec2D();
            this.theta = theta_p;
        }
        //due to lack-of int/float types, no support of theta in degrees
    }
function ( theta_p , theta ) { if ( arguments . length > 1 ) { this . theta = theta ; this . rootPos = new Vec2D ( theta_p ) ; } else { this . rootPos = new Vec2D ( ) ; this . theta = theta_p ; } //due to lack-of int/float types, no support of theta in degrees }
either Vec2D + angle 
@param {Vec2D | Number} vector | angle
@param {Number} [theta]
either Vec2D + angle