A Visual Guide to Graham’s Scan Graham’s scan is a method for finding the convex hull that encompasses all points on the plane. Below you’ll see an example of a convex hull. Graham’s scan starts by finding the point with the lowest y coordinate. If there are multiple points on the y-coordinate, the point with the smallest x-value is chosen. The points are sorted by polar angles in counterclockwise rotation. Graham’s scan utilizes the stack. Points are pushed onto the stack. If the point is not part of the convex hull, the point is popped from the stack. Let’s look