Each 90° clockwise turn takes a point (x,y) and transforms it to (y,-x). For a 180° turn you would do this process twice in a row; for a 270° turn, three times in a row.
Each 90° clockwise turn takes a point (x,y) and transforms it to (y,-x). For a 180° turn you would do this process twice in a row; for a 270° turn, three times in a row.
