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Main loop: Main flight loop (Part 6 of 16)

[BBC Micro disc version, Flight]

Name: Main flight loop (Part 6 of 16) [Show more] Type: Subroutine Category: Main loop Summary: For each nearby ship: Move the ship in space and copy the updated INWK data block back to K% Deep dive: Program flow of the main game loop Program flow of the ship-moving routine Ship data blocks
Context: See this subroutine in context in the source code References: No direct references to this subroutine in this source file

The main flight loop covers most of the flight-specific aspects of Elite. This section covers the following: * Continue looping through all the ships in the local bubble, and for each one: * Move the ship in space * Copy the updated ship's data block from INWK back to K%
.MA21 JSR MVEIT \ Call MVEIT to move the ship we are processing in space \ Now that we are done processing this ship, we need to \ copy the ship data back from INWK to the correct place \ in the K% workspace. We already set INF in part 4 to \ point to the ship's data block in K%, so we can simply \ do the reverse of the copy we did before, this time \ copying from INWK to INF LDY #NI%-1 \ Set a counter in Y so we can loop through the NI% \ bytes in the ship data block .MAL3 LDA INWK,Y \ Load the Y-th byte of INWK and store it in the Y-th STA (INF),Y \ byte of INF DEY \ Decrement the loop counter BPL MAL3 \ Loop back for the next byte, until we have copied the \ last byte from INWK back to INF