坐标系旋转的知识

 

X y 点 逆时针旋转b角到c d 如下

c= xcos(β)-ysin(β)

d= ycos(β)+xsin(β)

顺时针也即坐标轴逆时针

s =  os = oa + as = x cos(theta) + y sin(theta) 
t =  ot = ay – ab = y cos(theta) – x sin(theta)