Nestopia Core

[Cepheidsong]

I've done a lot of trying to compare NES emulators by myself in the past, and Nestopia has always come out as crisper and cleaner, most especially and noticeably in the audio/music department. Since there is look into updating cores, I wanted to see if I could get an opinion if it would be worth replacing FCEUX in Provenance with Nestopia. When doing some research, a lot of the RetroPie emulator players seem to prefer Nestopia also, but I don't know of any compatibility issues with Provenance, or if there is a reason for FCEUX preference I don't know about.

I want to look more into this myself even, and try to figure it out despite my little knowledge of Xcode, but just wanted to see anyone's feedback.

[sevdestruct]

@Cepheidsong… I haven't heard anyone having any issues with the current NES core recently (and I just finished a huge comb-through spring-cleaning of the entire Issues board…), so I doubt you're going to get much traction at the moment as that sounds lower priority than the new core additions ahead of this, unless you want to take this on yourself and submit a PR, which you are more than welcome to.

There is work ahead to get Per-Core Configs (#680) in and, additionally, support for switching core preference, as we currently have overlapping cores right now that aren't accessible to the users. You could submit your core addition for once core-swapping is implemented. I've added it to the Core Additions project for tracking purposes in the meanwhile…

[Cepheidsong]

Okay, thanks! I'll try using this as a learning experience and see what I can do about it as a side-project and then see if anyone likes it.

[sevdestruct]

@Cepheidsong: if you are going to take it on, I recommend you take a look at and clone the work off the UIRedesign branch, which has the latest work being done on the core framework that @JoeMatt has been working on - good chance you'll need to start with a clean install of Provenance, so you might want to back up your game saves/data before you delete the app.

[JoeMatt]

We will eventually be in a position to support multiple cores per system type. I'm finishing up some work to separate the concept of core and system in the code and make the scanning of such dynamic based on the frameworks in the app bundle, like OpenEmu's .oeplugins (though they need to be built into the app not downloaded after install like OpenEmu can).

A little trick to easily add new cores.

• Copy a sub-project for a core from OpenEmu
• Import it into the Provenance workspace
• Make a new target for an iOS framework in the copied OpenEmu core project
• Select the .oecore target from the sub-project targets. Go the 'build phases' tab, and expand the 'compile sources' table.
• Highlight all the sources in that list
• Right click and choose - 'Revel in project navigator'. Now they should all be highlighted in the file browser
• On Xcode's right pane where you can select the targets the files are associated to, select your new iOS framework target. Now all the sources are in the iOS target.
• Repeat with a tvOS framework

At this point you have to manually do some things

• Change OpenEmu's 'includes' to PVSupport frameowork. OEGameCore class to our equilvant 'PVEmulatorCore'
• Add any frameworks to be linked, usually about the same as OpenEmu's but sometimes they change, like Cocoa.framework would be Foundation and UIKit, OpenGL would be OpenGLES etc.
• Look at the compiler flags for the OpenEmu target. They use x86 and OpenGL. Search the code and see if you have to change -D's to OpenGLES or GLES2 or something like that. It helps to google around for apps like librertro or other open source projects that also use the same sub-projects as cores and look what their compiler flags are for Android and iOS builds if they have in their Makefile or CMake files. I usually learn a lot about the nuances of optimisation flags here. Sometimes projects have things like #if MACOSX that needs to be changed to MACOSX || IOS and add a new -DIOS to the preprocessor flags if they have stuff like handling OS X file systems etc.
• IF the core uses OpenGLES, somethings the #includes are for Android mobile only and need to be changed to <OpenGLES/ES2/glex.ht> and few others. Search the Workspace for other places I did this already, like PicoDrive, Mupen, Mednafen etc.

If the framework compiles for iOS. It's time to link it to the the Provenance app target, add systems.plist data, add it to the Core facrtory classes and hook up controller input callbacks from PVEmulatorViewController etc.

It sounds like a lot but I've gotten cores done in an evening for the simpler ones, though I've done about 7 of them now.

[sevdestruct]

@Cepheidsong: dev generosity right there, ⬆️…hope you have what you need to start your project.

[clobber]

OpenEMU

Hey, it's OpenEmu as in Emulator :P

[jasarien]

@Clobber! 🤟😆

[sevdestruct]

fixed/edited it for you, @clobber 😉 represent.

[sevdestruct]

@JoeMatt clobber just wanted the app name written correctly. but i think 'e was just jokin' - i did fix the typos though.