 20
                            
                                        20              
                            
                            
                     
                                                 20              
                            
                                        3D ture
                            
                                        20              
                            
                                        3D ture
                            
                     
                                                 13              
                            
                                        3D ture
                            
                                        13              
                            
                                        3D ture
                            
                     
                                                 20
                            
                                        20              
                            
                            
                     
                                                 8
                            
                                        8               
                            
                            
                    