splay is calculated by taking the bitwise OR of the new and old colors. On a monochrome display, this corresponds to drawing on a clear plastic overlay. The OR operation is applied to the indexes of the colors as opposed to their RGB values.</DD>
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MM_AND</DT><DD>The color value to display is calculated by taking the bitwise AND of the new and old colors. Where either drawing is blank, the result will be blank. On a monochrome display, this results in a &quot;clipping&quot; effect. The AND operation is a