Patent ID: 7773829

Claim:
A method, comprising: a computer performing: detecting a position of a pointer relative to an image on a display screen; drawing a ruler over the image so that the ruler extends outward approximately from the position of the pointer; detecting a panning of the image to another location on the display screen, or a rotating of the image relative to the display screen, and in response: moving the ruler automatically along with the image to the other location on the display screen if panning of the image is detected, wherein the ruler maintains its position and its orientation relative to the image during the panning of the image; or rotating the ruler automatically along with the image if rotating of the image is detected, wherein the ruler maintains its position and its orientation relative to the image during the rotating of the image; and moving the ruler so that it follows the pointer in response to detecting movement of the pointer about the display screen, wherein the ruler maintains its orientation relative to orientation of the image as the ruler follows the pointer.