The solution came in the form of a brilliant feat of coding Ingalls called “BitBlt,” an abbreviation of the term “bit boundary block transfer” that was pronounced “bitblit.” BitBlt was a way to shift whole rectangles, or blocks, of the bitmap from one location to another in a single operation. It enabled the system to bypass the tedium of delving into memory, locating all the components of the rectangular image, and changing them one by one; and thus cut out most of the computation that had made full-bitmap procedures so slow. Suddenly graphical changes on the display were faster, more direct,
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