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Feralstorm

Asteroids source/disassembly?

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I haven't done a lot of searching, but I have done some, and come up dry.

 

There's a lot of hacks of Asteroids out there - has anyone got source code/disassemblies for 2600 Asteroids? (preferably with comments, but I take what I can get)

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Thankyew.

 

I barely qualify as a hacker, but I've done a few things, and the variations of Asteroids in the FB2 started me thinking in "How I woulda dunnit" terms.

 

I don't have the programming skills (or the patience to learn) to do much beyond graphic hacks tho'

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Thanks again for the disassembly. I'm in the middle of a hack which will get lost in the wealth of Asteroids hacks out there, along with a test or two of graphic experiments. I'm just a bit-hacker, but there's a lot one can do in bit hacking when one has a roadmap.

 

Which leads me to a follow-up question for anyone willing to listen. Is there a way (with bit-hacking) to disable the difficulty switch check? My goal is to set the UFOs as on regardless of the switch position.

 

Thanx in advance

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Which leads me to a follow-up question for anyone willing to listen. Is there a way (with bit-hacking) to disable the difficulty switch check? My goal is to set the UFOs as on regardless of the switch position.

:idea: Search for SWCHB (probably BIT SWCHB) and where the two highest bits are checked (probably by bpl/bmi and bvc/bvs).

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Thanks again for the aid. I managed to do what I was shooting for mostly by trial and error, since I was bit-hacking as opposed to assembly-hacking. Sorta like turning on and off lamps in your home by pounding the circuit breaker with a hammer. :) No apparent side-effects so far, so I'm hopeful.

 

I also stared over, using Sadistroids as a baseline this time (since it already had a few things I wanted already in place.) Hope you don't mind... eheh.

 

Getting close to done either way - watch this space.

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I also stared over, using Sadistroids as a baseline this time (since it already had a few things I wanted already in place.) Hope you don't mind... eheh.

No problem. After all, it's only a hack.

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Okee-doke.

 

I'm beta-testing/playtesting and tweaking, mostly so the "slow" game doesn't totally kick my ass. :)

939741[/snapback]

 

In cases of checking just to make sure that the game mechanics work as expected, I usually add in cheat options to the assembly file (most game cheats are easily added by looking though the listing for collision register checks). For example:

 

      BIT CXPPMM;check player/player collisions
     BPL LXXXX;branch if no collision

 

...could be changed to be:

  IF CHEAT
     JMP LXXXX;always skip to the "no collsions" address
     NOP;extra byte
 ELSE
     BIT CXPPMM;check player/player collisions
     BPL LXXXX;branch if no collision
 ENDIF

 

Then at the top of the assembly, you can set CHEAT to be 0 or 1 before you assemble the binary.

 

'Course, not all games use collision registers ;)

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