📅  最后修改于: 2022-03-11 14:48:32.489000             🧑  作者: Mango
say you have 2 points, (x1,y1) and (x2,y2)
to get their corners, criss cross the x's and y's:
corner1 = x1,y2
corner2 = x2,y1
if the original points are on the same x-axis or same y-axis,
the criss cross result will give you back the original points