One of the major changes planned for the next release of PCSX2 is a complete overhaul of the gui/frontend, switching from the current "native" Windows/Linux interfaces to a single unified interface that's (more or less) the same for both platforms. To make such a grand vision possible we needed the help of a third party gui tooolkit, from which there were several to choose from. After much consideration we settled on wxWidgets , which is the same toolkit used by a few other notable emulators, such as Dolphin .
So what are the benefits of the new PCSX2 interface in development?
1. A vastly improved Linux interface.
... and not just in terms of what you see, but how the emulator cooperates with the operating system as a whole. wxWidgets provides dozens of very useful cross-platform tools that are much more well-suited to Linux functionality than the current PCSX2 codebase. The new interface will have a smarter plugin loader, and multilingual support as well. It will also be easier to install and run as a user other than root.
2. Windows XP/Vista Themed appearances will finally work!
Until now, PCSX2 used the old Win95 ASCII-based Common Controls libraries, and this forced Windows to disable themes support when rendering the PCSX2 interface. Buttons were plain and unshaded, and dialog boxes such as the File and Folder pickers were small, ugly, and lacking in features. All of this will be fixed in the next release.
3. More complete internationalization support.
Translations of the PCSX2 interface will be easier to make and maintain, and shouldn't become broken or obsolete from program updates, which was a persistent problem in the older PCSX2 interface design. In addition, PCSX2 will be fully Unicode compliant on both Windows and Linux platforms, which should help resolve various oddball problems the emulator may have encountered on non-English operating systems.
4. A more responsive multithreaded interface which will remain fully accessible even while games are running!
The new interface will run on its own thread separate from the emulator's EE/MTGS threads, allowing it to remain open and accessible in the background, without the need to shut down the GS window. This should improve the stability of "pausing" emulation, and also opens the door for expanding on interface integration; such as binding popup menus, toolbars, status bars, or other useful things to the GS window.
Furthermore, if a game deadlocks the system, the interface will usually remain responsive even as the rest of the emulator freezes up (which might not be much of a feature for end users, but is quite handy for us developers).
5. The Teaser Image!
And here's a sneak peek at the current GUI-Work-in-Progress:
... yeah it's not a whole lot to see yet -- I might post some more as development progresses.
From a coder's perspective:
In all the wxWidgets experience so far has been a decent one. There are a few annoyances, but those tend to be more the fault of cross-platform considerations (some things are not supported well under Linux, or vice versa), or more commonly due to limitations and design flaws in the C++ language itself rather than of wxWidgets (in particular, C/C++ make it especially difficult to work with unicode strings in a 'nice' way). For the most part wx tries to model itself in the image of the .NET Framework and Java Framework API designs, which are good designs to follow.