code: function Box(sx, sy, sz) {
    sx = sx != null ? sx : 1;
    sy = sy != null ? sy : sx != null ? sx : 1;
    sz = sz != null ? sz : sx != null ? sx : 1;
  
    Geometry.call(this, { vertices: true, faces: true });
  
    var vertices = this.vertices;
    var faces = this.faces;
  
    var x = sx/2;
    var y = sy/2;
    var z = sz/2;
  
    //bottom
    vertices.push(new Vec3(-x, -y, -z));
    vertices.push(new Vec3(-x, -y,  z));
    vertices.push(new Vec3( x, -y,  z));
    vertices.push(new Vec3( x, -y, -z));
  
    //top
    vertices.push(new Vec3(-x,  y, -z));
    vertices.push(new Vec3(-x,  y,  z));
    vertices.push(new Vec3( x,  y,  z));
    vertices.push(new Vec3( x,  y, -z));
  
    //     4----7
    //    /:   /|
    //   5----6 |
    //   | 0..|.3
    //   |,   |/
    //   1----2
  
    faces.push([0, 3, 2, 1]); //bottom
    faces.push([4, 5, 6, 7]); //top
    faces.push([0, 1, 5, 4]); //left
    faces.push([2, 3, 7, 6]); //right
    faces.push([1, 2, 6, 5]); //front
    faces.push([3, 0, 4, 7]); //back
  
    this.computeNormals();
  }
docs: ### Box ( sx, sy, sz ) `sx` - size x / width *{ Number = 1 }* `sy` - size y / height *{ Number = 1 }* `sz` - size z / depth *{ Number = 1 }*