OpenSceneGraph/examples/osgviewerSDL/osgviewerSDL.cpp

// C++ source file - (C) 2003 Robert Osfield, released under the OSGPL.
// (C) 2005 Mike Weiblen http://mew.cx/ released under the OSGPL.
// Simple example using GLUT to create an OpenGL window and OSG for rendering.
// Derived from osgGLUTsimple.cpp and osgkeyboardmouse.cpp

#include <osgViewer/Viewer>
#include <osgViewer/ViewerEventHandlers>
#include <osgGA/TrackballManipulator>
#include <osgDB/ReadFile>

#include "SDL.h"

#include <iostream>

bool convertEvent(SDL_Event& event, osgGA::EventQueue& eventQueue)
{
    switch (event.type) {

        case SDL_MOUSEMOTION:
            eventQueue.mouseMotion(event.motion.x, event.motion.y);
            return true;

        case SDL_MOUSEBUTTONDOWN:
            eventQueue.mouseButtonPress(event.button.x, event.button.y, event.button.button);
            return true;

        case SDL_MOUSEBUTTONUP:
            eventQueue.mouseButtonRelease(event.button.x, event.button.y, event.button.button);
            return true;

        case SDL_KEYUP:
            eventQueue.keyRelease( (osgGA::GUIEventAdapter::KeySymbol) event.key.keysym.unicode);
            return true;

        case SDL_KEYDOWN:
            eventQueue.keyPress( (osgGA::GUIEventAdapter::KeySymbol) event.key.keysym.unicode);
            return true;

        case SDL_VIDEORESIZE:
            eventQueue.windowResize(0, 0, event.resize.w, event.resize.h );
            return true;

        default:
            break;
    }
    return false;
}

int main( int argc, char **argv )
{
    if (argc<2)
    {
        std::cout << argv[0] <<": requires filename argument." << std::endl;
        return 1;
    }

    // init SDL
    if ( SDL_Init(SDL_INIT_VIDEO) < 0 )
    {
        fprintf(stderr, "Unable to init SDL: %s\n", SDL_GetError());
        exit(1);
    }
    atexit(SDL_Quit);
    

    // load the scene.
    osg::ref_ptr<osg::Node> loadedModel = osgDB::readNodeFile(argv[1]);
    if (!loadedModel)
    {
        std::cout << argv[0] <<": No data loaded." << std::endl;
        return 1;
    }

    // Starting with SDL 1.2.10, passing in 0 will use the system's current resolution.
    unsigned int windowWidth = 0;
    unsigned int windowHeight = 0;

    // Passing in 0 for bitdepth also uses the system's current bitdepth. This works before 1.2.10 too.
    unsigned int bitDepth = 0;

    // If not linked to SDL 1.2.10+, then we must use hardcoded values
    const SDL_version* linked_version = SDL_Linked_Version();
    if(linked_version->major == 1 && linked_version->minor == 2)
    {
	if(linked_version->patch < 10)
	{
	    windowWidth = 1280;
	    windowHeight = 1024;
	}
    }

    SDL_GL_SetAttribute( SDL_GL_RED_SIZE, 5 );
    SDL_GL_SetAttribute( SDL_GL_GREEN_SIZE, 5 );
    SDL_GL_SetAttribute( SDL_GL_BLUE_SIZE, 5 );
    SDL_GL_SetAttribute( SDL_GL_DEPTH_SIZE, 16 );
    SDL_GL_SetAttribute( SDL_GL_DOUBLEBUFFER, 1 );
    
    // set up the surface to render to
    SDL_Surface* screen = SDL_SetVideoMode(windowWidth, windowHeight, bitDepth, SDL_OPENGL | SDL_FULLSCREEN | SDL_RESIZABLE);
    if ( screen == NULL )
    {
        std::cerr<<"Unable to set "<<windowWidth<<"x"<<windowHeight<<" video: %s\n"<< SDL_GetError()<<std::endl;
        exit(1);
    }

    SDL_EnableUNICODE(1);
    
    // If we used 0 to set the fields, query the values so we can pass it to osgViewer
    windowWidth = screen->w;
    windowHeight = screen->h;
    
    osgViewer::Viewer viewer;
    osg::ref_ptr<osgViewer::GraphicsWindowEmbedded> gw = viewer.setUpViewerAsEmbeddedInWindow(0,0,windowWidth,windowHeight);
    viewer.setSceneData(loadedModel.get());
    viewer.setCameraManipulator(new osgGA::TrackballManipulator);
    viewer.addEventHandler(new osgViewer::StatsHandler);
    viewer.realize();

    bool done = false;
    while( !done )
    {
        SDL_Event event;

        while ( SDL_PollEvent(&event) )
        {
            // pass the SDL event into the viewers event queue
            convertEvent(event, *(gw->getEventQueue()));

            switch (event.type) {

                case SDL_VIDEORESIZE:
                    gw->resized(0, 0, event.resize.w, event.resize.h );
                    break;

                case SDL_KEYUP:

                    if (event.key.keysym.sym==SDLK_ESCAPE) done = true;
                    if (event.key.keysym.sym=='f') 
                    {
                        SDL_WM_ToggleFullScreen(screen);
                        gw->resized(0, 0, screen->w, screen->h );
                    }

                    break;

                case SDL_QUIT:
                    done = true;
            }
        }

        if (done) continue;


        // draw the new frame
        viewer.frame();

        // Swap Buffers
        SDL_GL_SwapBuffers();
    }
   
    return 0;
}

/*EOF*/