\ --- Mod: Code added for Demonstration Disc: ---------> .RefineApproach LDX #0 \ Set RAT2 = 0 STX RAT2 STX INWK+30 \ Set the pitch counter to 0 to stop any pitching EOR XX15 \ A is negative, so this sets the sign of A to the same EOR XX15+1 \ as -XX15 * XX15+1, or -ship_x * ship_y ASL A \ Shift the sign bit into the C flag, so the C flag has \ the following sign: \ \ * Positive if ship_x and ship_y have different signs \ * Negative if ship_x and ship_y have the same sign LDA #2 \ Set A = +2 or -2, giving it the sign in the C flag, ROR A \ and store it in byte #29, the roll counter, so that STA INWK+29 \ the ship rolls towards the target LDA XX15 \ If |ship_x * 2| >= 12, i.e. |ship_x| >= 6, then set ASL A \ the C flag so when we return from the subroutine, we CMP #12 \ jump to to PH22 to slow right down, as the target is \ not in our sights RTS \ Return from the subroutine \ --- End of added code ------------------------------->Name: RefineApproach [Show more] Type: Subroutine Category: Demo Summary: Refine our approach using pitch and roll to aim for the targetContext: See this subroutine in context in the source code References: This subroutine is called as follows: * AttackTarget calls RefineApproach * DOCKIT calls RefineApproach
The code in this routine has been copied from the DOCKIT routine in the disc version of Elite.