I have been working on a project where i am scanning a sketch and finding the largest and smallest X & Y values

In doing this I have been using the GetRotationDir function to determine the direction of arcs so i can then find out if the edge of the arc would determine my largest or smallest X value, but I have now found that if an arc is mirrored it will no longer returns the correct value.

Has anyone had this issue or know of a good fix for it?