The rules for negative rotation are as follows:
-90 degrees, the rule is (x, y) --------> (y, -x)
-180 degrees, the rule is (x, y) --------> (-x, -y)
-270 degrees, the rule is (x, y) --------> (-y, x)
The general rule for rotation of an object 90 degrees is (x, y) --------> (-y, x). ... When you rotate the image using the 90 degrees rule, the end points of the image will be (-1, 1) and (-3, 3). The rules for the other common degree rotations are: For 180 degrees, the rule is (x, y) --------> (-x, -y)