Drawing pixels: TWOS2

       Name: TWOS2                                                   [Show more]
       Type: Variable
   Category: Drawing pixels
    Summary: Ready-made two-bit pixel bytes for plotting colour pixels
    Context: See this variable in context in the source code
 References: This variable is used as follows:
             * CPIX uses TWOS2


 This table contains ready-made pixel bytes for drawing a one-pixel colour or
 two-pixel white dot in the high-resolution screen mode on the Apple II.

 Bit 7 in each byte is set, so when this is used as a mask byte via AND, it
 retains bit 7 (which sets the colour palette).

 The pixels in bits 0 to 6 appear in that order on-screen, so bit 0 is on the
 left. The comments below show how the bits map into the screen, with seven
 pixels per byte.

 See the CPIX routine for details.


.TWOS2

 EQUB %10000011         ; xx00000
 EQUB %10000110         ; 0xx0000
 EQUB %10001100         ; 00xx000
 EQUB %10011000         ; 000xx00
 EQUB %10110000         ; 0000xx0
 EQUB %11100000         ; 00000xx
 EQUB %11000000         ; 000000x