Abstract: An integer arithmetic graphic line scan-conversion procedure sub-divides a pixel grid into a 1/N sub-pixel grid, where N is a positive integer selected to provide a desired precision. A line segment is defined by a pair of vertices relative to the sub-pixel grid. The vertices are ordered such that the line segment is in one of the first and the second quadrants, depending upon the slope of the line segment. An integer estimate is made of the slope of the line segment relative to the sub-pixel grid. The scan progresses along a major axis at pixel intervals, while best-fit integer projections of the line segment are made along an orthogonal axis relative to the sub-pixel grid. A resulting array of integer line-scan points relative to the sub-pixel grid are used to adjust color and brightness attributes of display pixels, and the resulting adjusted pixels are output to a display device to create an image of the scanned line segment. In a preferred embodiment, N is a positive power of 2.

Abstract: An integer arithmetic graphic line scan-conversion procedure sub-divides a pixel grid into a 1/N sub-pixel grid, where N is a positive integer selected to provide a desired precision. A line segment is defined by a pair of vertices relative to the sub-pixel grid. The vertices are ordered such that the line segment is in one of the first and the second quadrants, depending upon the slope of the line segment. An integer estimate is made of the slope of the line segment relative to the sub-pixel grid. The scan progresses along a major axis at pixel intervals, while best-fit integer projections of the line segment are made along an orthogonal axis relative to the sub-pixel grid. A resulting array of integer line-scan points relative to the sub-pixel grid are used to adjust color and brightness attributes of display pixels, and the resulting adjusted pixels are output to a display device to create an image of the scanned line segment. In a preferred embodiment, N is a positive power of 2.

Abstract: Apparatus and methods are defined for increasing the effective bandwidth of a system bus for commanding a co-processor in an information processing system. The system processor commands the co-processor by sending a command block including one or more command parameters via the system bus. The bus includes an address phase and a data phase, and the effective bus bandwidth is increased by using a significant portion of the address phase and all of the data phase for sending the command parameters. The system processor disassembles the parameters and packs these into the address portion and the data phase of as few bus transfer commands as required. The co-processor includes a front end which receives the command and uses the command to select an appropriate procedure for unpacking and reassembling the received command parameters. Previous methods have transferred the command parameters using only the data phase of the system bus transfers.