Process for performing a windowing operation in an array move, a

Details Process for performing a windowing operation in an array move, a Process for performing a windowing operation in an array move, a

1993-12-03

1994-12-20

Herndon, Heather R.

395164, G06F 1562

Patent

active

053751981

ABSTRACT:
The present invention is a graphics data processor which includes the capability of determining whether a defined pixel location in a graphics display is within a window in an X Y coordinate system. The respective X and Y coordinates of the selected pixel are separately compared with the window limits. The window limits are preferable expressed as the X and Y coordinates of two diagonally opposite vertexes of a rectangular window. The results of this comparison are preferable available in two forms. In a first embodiment a single data processing instruction enables the generation of a digital data word which indicates the relation of the pixel to the window. This digital word includes a separate indication of the relationship of the pixel to the vertical and horizontal window limits. This indication can be used to generate a "trivial rejection" in determining whether a line or line segment passes through the window by ANDing the results for two points on the line. In a second embodiment the window compare capability is employed to determine whether or not a destination pixel is within the window. This is useful in array move instructions in which an entire array of pixels is moved to a location in the display. The array move may be aborted if a window violation is found or the move may be modified to plot to the display only those pixels within the window. This capability enables saving a great deal of time in graphics applications in which windows are employed by reducing the overhead needed for window determinations.

REFERENCES:
patent: 4257044 (1981-03-01), Fukuoka
patent: 4412296 (1983-10-01), Taylor
patent: 4481594 (1984-11-01), Staggs et al.
patent: 4495491 (1985-01-01), Postl
patent: 4598384 (1986-07-01), Shaw et al.
patent: 4779210 (1988-10-01), Katsura et al.
patent: 5077678 (1991-12-01), Guttag et al.
patent: 5185859 (1993-02-01), Guttag et al.
patent: 5283863 (1994-02-01), Guttag et al.

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