 20              
                            
                                        3D ture
                            
                                        20              
                            
                                        3D ture
                            
                     
                                                 17
                            
                                        17              
                            
                            
                     
                                                 7
                            
                                        7               
                            
                            
                     
                                                 13
                            
                                        13              
                            
                            
                    