Describe the wonderful tale about the Chinese painter Wu Daozi. What does the author mean by giving it?

Wu Daozi was a famous painter of China of eighth century. His painting, ‘landscape’, was commissioned by the Tang Emperor Xuanzong to decorate the palace wall. Wu Daozi requested the Emperor to look at the cave in the painting in which lived a spirit. The painter clapped his hands. The cave opened and the painter entered it. But its door closed behind him. The painting vanished from the wall. The artist was not seen thereafter nor any trace of his brush etc.

By this the author means to say that Chinese classical painting can be entered from any point. It is actually the spiritual and conceptual space. The artist creates a path for the viewer’s eye to enter the landscape. He doesn’t want the onlooker to borrow his eyes as happens in the case of European painting.