Since the OLPC XO computer has a 200 DPI display, the rulers are quite accurate. One other hardware, where the display resolution is not known, their is a spinner to let the user set the DPI. Ruler saves this value to the Journal, so it need not be set on subsequent uses of the Activity. | Since the OLPC XO computer has a 200 DPI display, the rulers are quite accurate. One other hardware, where the display resolution is not known, their is a spinner to let the user set the DPI. Ruler saves this value to the Journal, so it need not be set on subsequent uses of the Activity. |