更簡單的立體模型

更簡單的立體模型

靈感：https://www.google.com/imgres? q=escher stairs & imgurl=https：//media.nga.gov/iif/e6eb5003-aa1d-4425-b604-aef1c71d0346/full/！588，600/0/默認(rèn).jpg & imgrefurl=https：www.nga.gov/collection/art-object-page.54256.html&docid=qtDFPv7Kivoa3M&tbnid=e_wAl_9FuYs8pM&vet=12ahUKEwjExqLz4ueHAxXScvEDHbaPCsMQM3oECBoQAA.. i & w= 588 & h = 577 & hcb = 2 & ved =2ahUKEwjExqLz4ueHAxXScvEDHbaPCsMQM3oECBoQAA