don't click here

Porting any Sonic Megadrive game to SNES

Discussion in 'Engineering & Reverse Engineering' started by Hez, Oct 7, 2014.

  1. Hez

    Hez

    Oldbie
    I had an argument with a coworker the other day about the Genesis and the SNES. Long story short, it got to the conversation about how games would play on the other console. I've seen plenty of games that were released for both Genesis and SNES. Question I have....has anyone ever actually attempted to port the game to the SNES? Sonic 1 2 or 3?

    Genuinely curious how difficult it would be, or if possible at all.
     
  2. Might be possible, but you're going to have to optimize it. 3.54MHz do not a fast system make :P
     
  3. ICEknight

    ICEknight

    Researcher Researcher
    I would be interesting to see if the optimizations made for Sonic Classic Heroes would be enough for the port.

    In any case, there's nothing that could be done about the narrower screen resolution unless the game is set to run at one of the hi-res modes, but more complications may arise from attempting that.
     
  4. Machenstein

    Machenstein

    Member
    830
    0
    0
    I don't know about porting Sonic games to Super Nintendo, but a classic Sonic game on the Super Nintendo would be an interesting fan-game idea. A "what if" scenario, so to speak. Sonic Pocket Adventure to me is what a classic Sonic game on the NES would be like (though that was on the Neo Geo Pocket Color) so a Super Nintendo one would be neat. It could be either a fangame or even an elaborate SNES homebrew title.
     
  5. winterhell

    winterhell

    Member
    1,165
    7
    18
    We know that many multiplatform games run slower on the SNES. Still would be nice to see if nintendo really cant pull off a Sonic.
     
  6. RetroKoH

    RetroKoH

    Member
    1,662
    22
    18
    Project Sonic 8x16
    Well, I DO know that someone ported the original Super Mario Bros to the Mega Drive... so the basic argument of porting from system to system IS possible. (But of course that's already been proven obvious... DUH)
    NOW... as for porting Sonic from Mega Drive to SNES... I'm afraid I don't know nearly enough about the SNES to give any sort of legit answer... but I'm of the camp that it'd be an awesome endeavor.

    For what it's worth, I'm plugging an SNES ROM into IDA just to see if I can get a feel for working with SNES code on IDA (which I've started to become semi-proficient with) I'd suggest going with the M6502 processor setting... I'll update you guys with any progress I make (Which will be limited at best, I don't have the most time for this right now)
     
  7. Black Squirrel

    Black Squirrel

    no reverse gear Wiki Sysop
    8,608
    2,485
    93
    Northumberland, UK
    steamboat wiki
    The 256x224 resolution would give you trouble, but I think it's mainly just a speed thing. Given that Sonic games often lag on the Mega Drive when put under strain (namely, losing lots of rings or doing split-screen two player in Sonic 2), I get the impression it would probably cripple a SNES, but if you were going to go down the route of utilising extra chips a la StarFox, you might be able to work some magic.


    Coincidentally I was watching this video earlier today, which talks about attempts at bringing Doom to the Amiga. In 1993 it wasn't a cost-effective idea, but once sales stopped mattering, the hobbiests got close. It would be an interesting experiment... although obviously it has to fail because 90s Sega fanboyism :v:

    (also what happened to that homebrew Sonic game on the NES that was once talked about)
     
  8. flamewing

    flamewing

    Emerald Hunter Tech Member
    1,161
    65
    28
    France
    Sonic Classic Heroes; Sonic 2 Special Stage Editor; Sonic 3&K Heroes (on hold)
    I'd say it would make the end game horrible, either compressed horizontally or having bits chopped off the sides.

    Most likely this. The SNES' processor could run one instruction faster than the Genesis (I think it was the multiplication instruction) at their "native" frequencies, but even this one ended up being slower in practice because most SNES games underclocked the processor to 2.5something. But worse is that the number of sprites in the SNES was far more limited than in the Genesis — check Gunstar Heroes and the lack of SNES equivalents for an example.

    You mentioned Starfox?.
     
  9. Hez

    Hez

    Oldbie
    IRONICALLY that's the exact video that put the idea/argument in me and my coworkers head.

    So with extra chips, it's a maybe? I really want to see a concept of this.
     
  10. Cooljerk

    Cooljerk

    NotEqual Tech, Inc - VR & Game Dev Oldbie
    4,505
    201
    43
    It'd probably play a lot like Uniracers.
     
  11. InvisibleUp

    InvisibleUp

    friendly internet ghost Member
    139
    13
    18
    You might be able to get somewhere with the SA1 chip. It's a coprocessor clocked at 10.74 MHz that runs independent of the SNES CPU. Unfortunately the only real documentation is in the official SNES Dev manual, which isn't awful but it was written for people who knew what they were doing.

    Also, Sonic 1 special stages with smooth rotation would be amazing.
     
  12. flamewing

    flamewing

    Emerald Hunter Tech Member
    1,161
    65
    28
    France
    Sonic Classic Heroes; Sonic 2 Special Stage Editor; Sonic 3&K Heroes (on hold)
    Considering that this video is done in an unmodded Genesis, and considering that the original Starfox had a comparable framerate using an external chip, it will take more than a few chips... but yeah, with enough chips, you can do anything: at worst, you put a Genesis SOC on the cartridge and make it do everything, but that is kind of cheating...
     
  13. Blastfrog

    Blastfrog

    See ya starside. Member
    I'd rather see it attempted with a plain vanilla SNES with nothing added. I would think these approaches are a good idea:

    1. Optimize the hell out of the code and make sacrifices where it may not be noticed.
    2. Maybe slow Sonic's max speed to 5 pixels per frame so that it doesn't look excessively fast.
    3. Have an SCD-style pan forward when running.
    4. Scale what art you can down to 80% original scale horizontally so that at least those don't look distorted.
     
  14. Hez

    Hez

    Oldbie
    I don't think any scaling of sprites would be necessary. the Sonic CD panning would be enough.
     
  15. Stealth's Sonic 1 for GBA does fine with 240x160.
     
  16. Pexs

    Pexs

    Otherwise known as Spex Member
    Anyone ever try this?]

    Because loading Genesis cartridges on the SNES is totally a thing.
     
  17. gold lightning

    gold lightning

    Member
    507
    14
    18
    Yeah... I wouldn't count a console-on-a-chip that happens to use the SNES as a power source.
     
  18. Lilly

    Lilly

    Member
    2,428
    238
    43
    United States
    Shang Mu Architect
    I guess if something like this were to be done, Sonic 1 would be the best to port over? It's the one Genesis game that's the most documented, from what I can tell, unless Sonic 2 by itself is more optimized.

    It's actually possible in the vanilla game, but the programmers turned off smooth rotation. (I don't know why, but somebody mentioned something about motion sickness.) Quite a few hacks in the works right now are turning it back on, and it looks amazing. Add that to the variable jump height more hacks are including, and Sonic 1's Special Stages are legitimately playable to me.

    Yikes. I take it the number of rings Sonic can drop would have be cut down dramatically because of that. (16 versus 32 isn't too bad.) The SNES's resolution is also lower, so less sprites would be on-screen, but that might only marginally help with the limits of the video hardware, as you mentioned.
     
  19. Covarr

    Covarr

    Sentient Cash Register Member
    4,233
    3
    18
    Trapped in my own thoughts.
    Two stageplays, a screenplay, and an album
    It's not just about screen real estate. It's about the fact that the pixels aren't square. It'll display at 4:3, and all the sprites will look too wide.
     
  20. Felik

    Felik

    Member
    1,856
    82
    28
    How does Retro-Gen work?