Window dependent pixel datatypes in a computer video graphics system

In a computer video graphics system capable of displaying a plurality of windows on a monitor, the system having a frame buffer having pixels, a plurality of color lookup tables, and a processor including an electronically alterable mapping memory, a method of displaying different datatypes and formats for different windows comprising the steps of:

• a. providing a window number for each pixel in the frame buffer;
• b. providing a mapping configuration word corresponding to each window number, each of said mapping configuration words comprising a mode field, a shift field, a pixel bit mask field, and a color map base address field;
• c. for each window, performing steps comprising:
• shifting each pixel value of the window by an amount contained in the shift field of the mapping configuration word associated with the window;
• masking selected bits of the shifted pixel value, said selected bits determined by the pixel bit mask field of the mapping configuration word associated with the window;
• in the event the mode field of the mapping configuration word associated with the window matches a first selected value, processing the pixel values by multiplexing the masked pixel value and adding each multiplexed pixel value to the color map base address field;
• and
• in the event the mode field of the mapping configuration word associated with the window matches a second selected value, processing the pixel values by dividing the masked pixel value into multiple color channels and adding each of said color channels to the color map base address field;
• and
• d. providing the processed pixel values to the color lookup tables for display.