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PostPosted: Tue Apr 18, 2017 4:12 pm 
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Something's wrong... or I believe so. They've added emulation rewind. Yes, the feature discussed HERE & implemented by a few emulators is now present in this official compilation.

Did they get the source code without permission to incorporate on their project? AFAIK, this Capcom project is not open source, so... What do you think about it?


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PostPosted: Tue Apr 18, 2017 4:20 pm 
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https://en.wikipedia.org/wiki/Backbone_ ... pse_Engine


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PostPosted: Tue Apr 18, 2017 4:27 pm 
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Revenant wrote:
https://en.wikipedia.org/wiki/Backbone_Entertainment#Eclipse_Engine

It's an ancient idea that I never understand it. Well, let me change the question. Are the MegaMan ROMs included in the PC program?


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PostPosted: Tue Apr 18, 2017 4:33 pm 
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I'm pretty sure that rewinding in games wasn't invented by NESDev people. I think that Prince of Persia: The Sands of Time, for example, predates the use of this feature in any emulator. This is a pretty generic mechanic really, like jumping or attacking, so I don't see it as something "copyrightable" that can be "stolen".


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PostPosted: Tue Apr 18, 2017 4:40 pm 
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And the Prince of Persia people were inspired by a Donald Duck game that had rewinding.


Back to the original topic...
I was watching Frank Cifaldi's video about how his team did the port of Megaman legacy collection to modern C code. It's a port, decompiled from the ASM, but done as C code, and it still does writes to an emulated PPU and everything. But they can add new featues into the game in modern way, since they can edit the C code, and skip the emulated PPU.
Companies are scared of using a real emulator for some reason, and want a port instead so they can avoid legal risks.

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PostPosted: Tue Apr 18, 2017 5:09 pm 
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Dwedit wrote:
Back to the original topic...

Wait, wasn't "rewinding" the original topic? The engine was mentioned in a reply...


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PostPosted: Tue Apr 18, 2017 5:15 pm 
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My (hasty) reply was just to point out that the Digital Eclipse / Capcom game collections don't use third-party emulators. Dwedit elaborated on it nicely.


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PostPosted: Tue Apr 18, 2017 6:02 pm 
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"A port"... as easy as 2+2=4. Yeah. I'd like an example of such thing in the community, one example of porting a NES game from ASM to C. The only idea was a NES C compiler + user interface. An ancient emulator named "PCNES" had an "ability" to be encapsulated with an single ROM to be "executable" in a PC, do you remember it?

About the rewind, I said it is/was an ancient idea, BUT the idea of applying it in NES emulators has been born here... OR do you really think that a 20-years-old guy from the Eclipse team had an idea (an insight) about "why not a rewind feature, like they did in Prince of Persia back in 80s"? No.


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PostPosted: Tue Apr 18, 2017 6:25 pm 
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You do know who Frank Cifaldi is, right? He's a legend. He ran theredeye.net way back in the day (2002-2005), a rom release site for rare, obscure, and prototype games, complete with screenshots of 8-bit nudity. Then he ran lostlevels.org, a prototype rom release blog and discussion site which looks far more clean and professional, due to less foul language and no more nudity. Then he did a bunch of random writing jobs for gaming news sites.

He also originated the comment suggesting that "Nintendo sold you a ROM they downloaded from the internet", which went viral.

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PostPosted: Tue Apr 18, 2017 6:41 pm 
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Dwedit wrote:
I was watching Frank Cifaldi's video about how his team did the port of Megaman legacy collection to modern C code. It's a port, decompiled from the ASM, but done as C code, and it still does writes to an emulated PPU and everything. But they can add new featues into the game in modern way, since they can edit the C code, and skip the emulated PPU.
Companies are scared of using a real emulator for some reason, and want a port instead so they can avoid legal risks.

That and for a period of several months years ago, Apple's App Store Review Guidelines required a port because Apple was trying to kill Adobe AIR. Apple wouldn't sign an app for distribution to the public for use on iOS devices unless its source code (that is, the preferred form for making modifications to the program) was in either Objective-C++ or JavaScript. If you want sources, I can dig them up.

But I agree that rewinding in general isn't proprietary to the emulation scene.


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PostPosted: Tue Apr 18, 2017 6:43 pm 
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Dwedit wrote:
You do know who Frank Cifaldi is, right?

Nope. :mrgreen:
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He's a legend.

Wow. :shock:
Quote:
He ran theredeye.net way back in the day (2002-2005), a rom release site for rare, obscure, and prototype games, complete with screenshots of 8-bit nudity. Then he ran lostlevels.org, a prototype rom release blog and discussion site which looks far more clean and professional, due to less foul language and no more nudity. Then he did a bunch of random writing jobs for gaming news sites.

He also originated the comment suggesting that "Nintendo sold you a ROM they downloaded from the internet", which went viral.

Fine. Now I'd like a proof of concept - take a NES ROM and convert it to a PC-executable or C source code. As I said, it's an ancient concept that I never saw it.


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PostPosted: Tue Apr 18, 2017 7:04 pm 
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Can't find any sources right now, but I remember an interview where the developers of Sonic CD for PC said they too used a tool to convert the original 68000 code into C, way back in '96.


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PostPosted: Tue Apr 18, 2017 7:26 pm 
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The only nearest think I can remember is dynamic recompilation, used in Nintendo64 emulators as a "shiny" speed resource. Perhaps I'm not phrasing my thoughts correctly. Converting 6502 code to C isn't a common practice, but emulating the system. Do you remember the MegaMan Mania, for Gameboy Advance? It was cancelled due to the lack of the original source code? Well, no GBA to C technique that time, eh?


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PostPosted: Tue Apr 18, 2017 7:33 pm 
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Zepper wrote:
Now I'd like a proof of concept - take a NES ROM and convert it to a PC-executable or C source code. As I said, it's an ancient concept that I never saw it.

There is MULS, a transpiler-assisted port of Super Mario Bros. to 68000 assembly language for use with a Sega Genesis. There is also a C preprocessor macro pack for translating x86 assembly. And Microchess ported from 6502 on KIM-1 to C.


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PostPosted: Tue Apr 18, 2017 7:34 pm 
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Couldn't find anything about a tool, but this interview contains the following bit:
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The amazing bit was how they translated the game from assembler to C, because the code was very funny -- when I read it on the screen (I don't have a copy) in the office in Tokyo, it was obvious that the C code was "emulating" the assembler code logic, rather than being a "fresh re-design".


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