[Tuxpaint-devel] plug-in API changes

[Albert C. <aca...@gm...>]

I'm planning to change things as follows. I hope it
does not cause trouble for anybody. Let me know
if you see any problems.

//////////////////////////////////////////
static int bigbricks_click(int x, int y, SDL_Rect * update_rect){
    ....
}

static int smallbricks_click(int x, int y, SDL_Rect * update_rect){
    ....
}

static int bigbricks_release(int x, int y, SDL_Rect * update_rect){
    ....
}

static int smallbricks_release(int x, int y, SDL_Rect * update_rect){
    ....
}

static struct fns{
    .click = bigbricks_click;
    .release = bigbricks_release;
    ...
}bigbricks;

static struct fns{
    .click = smallbricks_click;
    .release = smallbricks_release;
    ...
}smallbricks;

// see below for what PLUG_FUNCTION is about
void PLUG_FUNCTION init(...){
    register_magic(&bigbricks);
    register_magic(&smallbricks);
}
////////////////////////////////////////

Note that left-out functions become NULL. The core
can substitute do-nothing functions as required, or
just check for NULL. (checking at every call is messier
there, but would allow for a const struct that can be
directly used)

The tools call directly into the core. To enable this,
various core functions are marked for export, essentially
like this:

#ifdef WIN32
__declspec(dllexport)
#else
__attribute__((visibility(default)))
#endif

(with a proper define of course, under Makefile control)

That should allow hidden visibility to work, which will
slightly improve start-up performance.

The real goal here is to simplify the problem of making
it possible to build Tux Paint with all the tools compiled in.