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⌂ ∞ ▽ The Sentinel on the BBC Micro

Graphics: DrawStars

       Name: DrawStars                                               [Show more]
       Type: Subroutine
   Category: Graphics
    Summary: Draw 80 randomly positioned stars on the screen in colour 2
             (white, yellow, cyan or red)

    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * ClearScreen calls DrawStars




.DrawStars

 LDA #%10000000         \ Set bit 7 of A to pass to the DrawRandomDots routine
                        \ so we draw random dots on-screen in colour 2 to look
                        \ like stars

 BNE DrawRandomDots     \ Jump to DrawRandomDots to draw 80 coloured dots on the
                        \ screen (this BNE is effectively a JMP as A is never
                        \ zero)