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⌂ ∞ ▽ Aviator on the BBC Micro

3D geometry: SetObjectCoords (Part 3 of 11)

       Name: SetObjectCoords (Part 3 of 11)                          [Show more]
       Type: Subroutine
   Category: 3D geometry
    Summary: Logic for checking which objects to pre-process
  Deep dive: 3D objects

    Context: See this subroutine in context in the source code
 References: No direct references to this subroutine in this source file




.objc1

                        \ If we get here then this is not a bullet

 LDA N                  \ Set GG = N
 STA GG                 \        = 216 + object ID
                        \
                        \ so GG contains the point ID that we use for storing
                        \ the object's anchor point

 CPY #6                 \ If the object ID < 6, jump to objc3 to check the next
 BCC objc3              \ range

 CPY #10                \ If the object ID >= 10, jump to objc3 to check the
 BCS objc3              \ next range

                        \ Otherwise the object ID is 6, 7, 8 or 9, so fall
                        \ through into part 4 to pre-process the object