The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 28, 1995
Filed:
Dec. 30, 1993
Darwin P Rackley, Boca Raton, FL (US);
R Michael West, Colchester, VT (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Method and apparatus for adjusting the color of the sprite in display systems, so that the sprite is always distinctively visible irrespective of the underlying displayed data. A palette DAC of a display system is provided with sprite control logic, which derives the color of a sprite to be overlaid on an image displayed on a video display unit of a display system by inverting only the most significant bit (MSB) of each of the red, green and blue pixel data components of the underlying image. In a preferred embodiment, the sprite control logic circuit comprises first, second and third multiplexors (MUXes) each having a first input connected to receive the MSB of the red, green and blue pixel data components of the underlying image, respectively, and a second input connected to receive the output of first, second and third XOR gates, respectively. Each of the first, second and third XOR gates similarly have a first input connected to receive the MSB of the red, green and blue pixel data components of the underlying image, respectively, and a second input connected to receive sprite data from a sprite RAM, which sprite data represents a sprite character to be overlaid on the displayed image.