translate(vec) {
    let movement = vec3.zero.slice();
    vec3.add(movement, this.position, vec);
    this.position = movement;
  }
// other than the local space (relative to the parent).
other than the local space (relative to the parent).
other than the local space ( relative to the parent ) .
translate(vec) {
    let movement = vec3.zero.slice();
    vec3.add(movement, this.position, vec);
    this.position = movement;
  }
translate ( vec ) { let movement = vec3 . zero . slice ( ) ; vec3 . add ( movement , this . position , vec ) ; this . position = movement ; }
other than the local space (relative to the parent).
other than the local space ( relative to the parent ) .