more GUI Widgets

[FrMo]

The first agar GUI objects were introduced with gravit 0.5.0 (issue #41).

In addition to keyboard shortcuts, the console and customiation via gravit.cfg/screensaver.cfg, all major functions should be availeable via menues or other clickable objects.

[FrMo]

Meanwhile, it seems that agar is on a trip to "refactoring hell". The API of the svn trunk is totally different, no new releases since 1.4.1, problems with 64-bit windows, no pre-build packages availeable on linux, no signs of support for the new SDL2.

We need to go for something different, for example:

• CEGUI, which seems to support SDL (http://cegui.org.uk/wiki/How_to_use_CEGUI_with_SDL_and_OpenGL)
• Guichan, designed for games using Allegro, SDL and/or OpenGL (http://guichan.sourceforge.net/oldsite/features.shtml)

@gak: do you have experiences with one of these? (I am a lousy GUI programmer, so I'd like to rely on you to make gravit look&feel awesome)

[gak]

I have played with CEGUI, and looked into it for Gravit. I chose not to use it because it was C++ and there was a C alternative. Haven't heard of Guichan before.

Both look fine and I have no issues with adding C++ into the code. Whatever is a more simple API imo.

[FrMo]

In fact, my experiences with C++ are very limited. I can live with some C++ files, but would prefer to keep the .c code free of C++ features; it should be simple to build extern "C" wrappers around the main GUI code.

Maybe it's a good idea to use a C++ GUI lib; agar seems to try being object-oriented with C, and the resulting API is horribly complicated; full of macros, casts, string parameters and void pointers...