We do direct pixel plotting using DCI in WIn3.11/95/98. As this gives us a handle to the Display Buffer and allows us to lock a portion of the screen, update any pixel in the display, and unlock it. We plot a line of pixels in a circle motion giving a radar like display. This dirty plotting gives a fast update rate for us. We need to do the same under NT4, can anyone help or direct me to a fast Direct X routine, or is this not so easy. I havn''t found a way to get direct access to the screen memory in NT yet, and NT does not like DCI. Any help most appreciated.