Main loop: Main game loop (Part 6 of 6)

       Name: Main game loop (Part 6 of 6)                            [Show more]
       Type: Subroutine
   Category: Main loop
    Summary: Process non-flight key presses (FUNC keys, docked keys)
  Deep dive: Program flow of the main game loop
    Context: See this subroutine in context in the source code
 Variations: See code variations for this subroutine in the different versions
 References: This subroutine is called as follows:
             * BAY calls via FRCE
             * TT219 calls via FRCE


 This is the second half of the minimal game loop, which we iterate when we are
 docked. This section covers the following:

   * Process more key presses (FUNC keys, docked keys etc.)

 It also supports joining the main loop with a key already "pressed", so we can
 jump into the main game loop to perform a specific action. In practice, this
 is used when we enter the docking bay in BAY to display Status Mode (FUNC-9),
 and when we finish buying or selling cargo in BAY2 to jump to the Inventory
 (FUNC-0).


 Other entry points:

   FRCE                 The entry point for the main game loop if we want to
                        jump straight to a specific screen, by pretending to
                        "press" a key, in which case A contains the internal key
                        number of the key we want to "press"


.FRCE

 JSR TT102              \ Call TT102 to process the key pressed in A

 LDA QQ12               \ Fetch the docked flag from QQ12 into A

 BNE MLOOP              \ If we are docked, loop back up to MLOOP just above
                        \ to restart the main loop, but skipping all the flight
                        \ and spawning code in the top part of the main loop

 JMP TT100              \ Otherwise jump to TT100 to restart the main loop from
                        \ the start