I have a general question regarding Autocad's Perpendicular Snap behavior. There are times when I am running Osnaps (with osmode set to 767) and I click near a line or intersection and the Osnap goes to a Perpendicular snap on the first click. This is different from the tentative perpendicular snap that shows the .. next to the snap symbol. This is the real snap point that starts the line at that exact point. I am confused by this since I can't understand how you can generate a perpendicular point with only one click. The perpendicular point must be perpendicular to something so I would think that you need at least two sources of input. Does anyone have an explanation for this?