3D geometry: SetPointVisibility

       Name: SetPointVisibility                                      [Show more]
       Type: Subroutine
   Category: 3D geometry
    Summary: Set the status byte for multiple points to indicate that their
             coordinates and visibility have been calculated
    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * ProcessRunwayLine (Part 2 of 5) calls SetPointVisibility
             * ProcessRunwayLine (Part 4 of 5) calls SetPointVisibility


 Arguments:

   X                    The ID of the point to update


.SetPointVisibility

 LDA #%10000000         \ Set bit 7 of point X's status byte, to indicate that
 ORA pointStatus,X      \ the point's coordinates and visibility have been
 STA pointStatus,X      \ calculated

 DEX                    \ Decrement X to point to the previous point

 BNE SetPointVisibility \ Loop back until we have set the status byte for points
                        \ X down to 1, i.e. points 1 to X

 RTS                    \ Return from the subroutine