mark@hpcvlx.HP.COM (Mark Rowe) (05/24/88)
A -1 -1 scale would in effect flip the image about the the x axis and then flip it about the y axis. This would result in the quadrant I portion of the image winding up in quadrant III but the double flip would leave the image uninverted. It is in effect a 180 degree rotation about the origin. Mark Rowe mark%hpcvlx@hplabs.HP.COM