double x = vec_endPoint_rotate.x(); double y = vec_endPoint_rotate.y(); double dx = vec_center_rotate.x(); double dy = vec_center_rotate.y(); //一個點(x,y)繞任意點(dx,dy)順時針旋轉a度后的坐標 double xx = (x - dx)*cos(angleParam* VC_PI / 180) - (y - dy)*sin(angleParam* VC_PI / 180) + dx; double yy = (x - dx)*sin(angleParam* VC_PI / 180) + (y - dy)*cos(angleParam* VC_PI / 180) + dy;