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⌂ ∞ ▽ The Sentinel on the BBC Micro

Graphics: clearPixelMask

       Name: clearPixelMask                                          [Show more]
       Type: Variable
   Category: Graphics
    Summary: A table for converting a pixel number in the range 0 to 3 into a
             screen mode 5 bit mask with that pixel's bits clear and others set

    Context: See this variable in context in the source code
 References: This variable is used as follows:
             * DitherScreenBuffer uses clearPixelMask
             * DrawSights uses clearPixelMask




.clearPixelMask

 EQUB %01110111         \ Pixel bit mask with all pixels set except pixel 0

 EQUB %10111011         \ Pixel bit mask with all pixels set except pixel 1

 EQUB %11011101         \ Pixel bit mask with all pixels set except pixel 2

 EQUB %11101110         \ Pixel bit mask with all pixels set except pixel 3

 EQUB %10001000         \ These bytes appear to be unused
 EQUB %01000100
 EQUB %00100010
 EQUB %00010001