main.h

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/*
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/

#ifndef OMGUI_MAIN_H
#define OMGUI_MAIN_H

#include <omgui/app.h>
#include <omgui/dllimpexp.h>

#ifdef OMGUI_WIN32
#include <windows.h>
#endif

namespace omgui {

omgui::App *main(const omgui::App::cmd_line &cmd);
typedef omgui::App *(main_ptr)(const omgui::App::cmd_line &);

// win32 has a different entry function, and omgui::entry function than other ports
#ifdef OMGUI_WIN32
    int OMGUI_API entry(main_ptr, HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow);
#else // !OMGUI_WIN32
    int OMGUI_API entry(main_ptr, int argc, char *argv[]);
#endif // OMGUI_WIN32

} // omgui

// platform specific entry function
// only include this part in user applications

/*
Explanation for the following code:

  The plan is to avoid requiring an IMPLEMENT_APP macro which declares the entry functions.
  Instead of the macro, omgui uses omgui::main() as an applications
  first entry point. omgui::main() is expected to create a omgui::App derivative and give that
  object to omgui. This omgui::App object is the actual application, and all further code execution
  is routed through this class.

  Because win32 dll's are not capable of calling a function defined in an application dll and prototyped
  in the dll headers, I cannot put the entry functions into the omgui library itself. To work around this
  restriction, I declare and implement them here, heavily if guarded. I realize this file could be included
  in two different source files, which causes multiply defined sybmols, but that is the fault of the programmer
  as this file is only required to be included once.

  The purpose of omgui::entry is to avoid implementing more code than is neccessary in this header file,
  allowing for at least slight binary compatability between changes so long as this header file is not modified.
  entry will call app->init(), and app->run() to actually run the application.

  omgui::entry is given a pointer to the omgui::main() function, as well as native entry function arguments.
*/
#if !defined(OMGUI_ENTRY_IMPLEMENTED) && !defined(OMGUI_BUILDING)
#define OMGUI_ENTRY_IMPLEMENTED

#ifdef OMGUI_WIN32
    int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
    {
        return omgui::entry(omgui::main, hInstance, hPrevInstance, lpCmdLine, nCmdShow);
    }
#else // !OMGUI_WIN32
    int main(int argc, char *argv[])
    {
        return omgui::entry(omgui::main, argc, argv);
    }
#endif // OMGUI_WIN32

#endif // !defined(OMGUI_ENTRY_IMPLEMENTED) && !defined(OMGUI_BUILDING)

#endif // OMGUI_MAIN_H

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