# Visualization Library

A lightweight C++ OpenGL middleware for 2D/3D graphics

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# Basic Scene Setup

## Setting up the rendering of a simple scene

The following example shows how to implement a simple 3D application by simply subclassing the UIEventListener class. The example below uses the vlWin32 bindings but the concepts remain valid for other bindings as well.

Complete source: `src/examples/Win32_direct.cpp`

    #include <vlCore/VisualizationLibrary.hpp>
    #include <vlCore/Time.hpp>
    #include <vlGraphics/Rendering.hpp>
    #include <vlGraphics/SceneManagerActorTree.hpp>
    #include <vlGraphics/Geometry.hpp>
    #include <vlGraphics/GeometryPrimitives.hpp>
    #include <vlGraphics/Light.hpp>
    #include <vlGraphics/TrackballManipulator.hpp>
    #include <vlGraphics/UIEventListener.hpp>
    #include <vlGraphics/OpenGLContext.hpp>
    #include <vlWin32/Win32Window.hpp>

    class MyApplet: public vl::UIEventListener
    {
    public:
      MyApplet()
      {
        // allocate rendering and scene manager
        mRendering    = new vl::Rendering;
        mSceneManager = new vl::SceneManagerActorTree;
        mRendering->sceneManagers()->push_back( mSceneManager.get() );
      }

      // ----- UIEventListener -----

      virtual void initEvent()
      {
        // --- scene setup ---

        // bind the Transform with the transform tree of the rendring pipeline
        mCubeTransform = new vl::Transform;
        rendering()->transform()->addChild( mCubeTransform.get() );

        // create the teapot's Geometry and compute its normals to support lighting
        vl::ref<vl::Geometry> teapot = vl::makeTeapot( vl::vec3(0,0,0), 15 );
        teapot->computeNormals();

        // setup the effect to be used to render the teapot
        vl::ref<vl::Effect> effect = new vl::Effect;
        // enable depth test and lighting
        effect->shader()->enable(vl::EN_DEPTH_TEST);
        // add a Light to the scene, since no Transform is associated to the Light it will follow the camera
        effect->shader()->setRenderState( new vl::Light, 0 );
        // enable the standard OpenGL lighting
        effect->shader()->enable(vl::EN_LIGHTING);
        // set the front and back material color of the teapot
        // "gocMaterial" stands for "get-or-create Material"
        effect->shader()->gocMaterial()->setDiffuse( vl::gold );
        effect->shader()->gocMaterial()->setSpecular( vl::white );
        effect->shader()->gocMaterial()->setShininess( 60 );

        // add actor to the scene
        sceneManager()->tree()->addActor( teapot.get(), effect.get(), mCubeTransform.get()  );

        // --- render target, viewport, camera position ---

        // install the render target belonging to the opengl window
        rendering()->renderer()->setFramebuffer( openglContext()->framebuffer() );

        // set clear color to white
        rendering()->camera()->viewport()->setClearColor( vl::white );

        // define the camera position and orientation
        vl::vec3 eye    = vl::vec3(0,10,20); // camera position
        vl::vec3 center = vl::vec3(0,0,0);   // point the camera is looking at
        vl::vec3 up     = vl::vec3(0,1,0);   // up direction
        vl::mat4 view_mat = vl::mat4::getLookAt(eye, center, up);
        rendering()->camera()->setViewMatrix( view_mat );

        // --- trackball manipulator ---

        vl::ref<vl::TrackballManipulator> trackball = new vl::TrackballManipulator;
        // bind the camera to be manipulated
        trackball->setCamera( rendering()->camera() );
        // manipulate the camera's transform
        trackball->setTransform(NULL);
        // rotation pivot coordinates
        trackball->setPivot( vl::vec3(0,0,0) );
        // install the trackball
        openglContext()->addEventListener(trackball.get());
      }

      virtual void updateEvent()
      {
        // --- scene update ---

        // rotates the teapot around the Y axis 15 degrees per second
        vl::real degrees = vl::Time::currentTime() * 15;
        vl::mat4 matrix = vl::mat4::getRotation( degrees, 0,1,0 );
        mCubeTransform->setLocalMatrix( matrix );

        // --- rendering ---

        // set frame time (used for animation updates etc.)
        rendering()->setFrameClock( vl::Time::currentTime() );

        // execute rendering
        rendering()->render();

        // swap back and front buffers
        if ( openglContext()->hasDoubleBuffer() )
          openglContext()->swapBuffers();
      }

      virtual void resizeEvent(int w, int h)
      {
        // update viewport dimensions
        rendering()->camera()->viewport()->set( 0, 0, w, h );

        // update the projection matrix
        vl::mat4 proj_matr = vl::mat4::getPerspective( 60 /*FOV*/, (float)w/h, 5/*near plane*/, 100/*far plane*/);
        rendering()->camera()->setProjectionMatrix( proj_matr, vl::PMT_PerspectiveProjection );

        /* can also be done like this:
        (the camera already knows the viewport dimensions and aspect ratio)
        rendering()->camera()->setProjectionPerspective( 60, 5, 100 ); */
      }

      virtual void destroyEvent() {}

      virtual void enableEvent(bool) {}

      virtual void addedListenerEvent(vl::OpenGLContext*) {}

      virtual void removedListenerEvent(vl::OpenGLContext*) {}

      virtual void mouseMoveEvent(int, int) {}

      virtual void mouseUpEvent(vl::EMouseButton, int, int) {}

      virtual void mouseDownEvent(vl::EMouseButton, int, int) {}

      virtual void mouseWheelEvent(int) {}

      virtual void keyPressEvent(unsigned short, vl::EKey) {}

      virtual void keyReleaseEvent(unsigned short, vl::EKey) {}

      virtual void fileDroppedEvent(const std::vector<vl::String>&) {}

      virtual void visibilityEvent(bool) {}

      // ----- user methods -----

      const vl::Rendering* rendering() const { return mRendering.get(); }
      vl::Rendering* rendering() { return mRendering.get(); }

      const vl::SceneManagerActorTree* sceneManager() const { return mSceneManager.get(); }
      vl::SceneManagerActorTree* sceneManager() { return mSceneManager.get(); }

    public:
      vl::ref<vl::Rendering> mRendering;
      vl::ref<vl::SceneManagerActorTree> mSceneManager;
      vl::ref<vl::Transform> mCubeTransform;
    };

    int APIENTRY WinMain(HINSTANCE /*hCurrentInst*/, HINSTANCE /*hPreviousInst*/, LPSTR /*lpszCmdLine*/, int /*nCmdShow*/)
    {
      /* open a console so we can see the applet's output on stdout */
      vl::showWin32Console();

      /* init Visualization Library */
      vl::VisualizationLibrary::init();

      /* setup the OpenGL context format */
      vl::OpenGLContextFormat format;
      format.setDoubleBuffer(true);
      format.setRGBABits( 8,8,8,0 );
      format.setDepthBufferBits(24);
      format.setStencilBufferBits(8);
      format.setFullscreen(false);
      format.setMultisampleSamples(16);
      format.setMultisample(false);

      /* Initialize the OpenGL context and window properties */
      vl::ref<vlWin32::Win32Window> win32_window = new vlWin32::Win32Window;
      int x = 0, y = 0, width = 512, height= 512;
      win32_window->initWin32GLWindow(NULL, NULL, "Golden Teapot", format, x, y, width, height );

      /* bind the applet so it receives all the GUI events related to the OpenGLContext */
      win32_window->addEventListener( new MyApplet );

      /* show the window */
      win32_window->show();

      /* run the Win32 message loop */
      int res = vlWin32::messageLoop();

      /* deallocate the window with all the OpenGL resources before shutting down Visualization Library */
      win32_window = NULL;

      /* shutdown Visualization Library */
      vl::VisualizationLibrary::shutdown();

      return res;
    }
    // Have fun!

## Implementing a rotating cube using the vl::Applet utility class

Visualization Library comes with several utility components to quickly develop applictions under several GUI frameworks. The vl::Applet class is an utility class that implements an event-driven application with a default rendering pipeline. Below is a practical examples of how to implement a vl::Applet that renders a spinning cube and how to use it (unchanged!) with `Win32`, `MFC`, `Qt4`, `SDL` and `GLUT!`

The vl::Applet subclasses the UIEventListener in a way very similar to the MyApplet class seen in the example above, but provides a few useful "pre-packaged" services such as quitting the application by pressing ESC, swticthing to fullscreen by pressing F1, taking a screenshot by pressing F5, both tracball and ghost manipulators etc. See the documentation page of vl::Applet for more information.

Complete source: `src/examples/Applets/App_RotatingCube.hpp`

    #include <vlGraphics/Applet.hpp>
    #include <vlGraphics/GeometryPrimitives.hpp>
    #include <vlGraphics/SceneManagerActorTree.hpp>
    #include <vlGraphics/Rendering.hpp>
    #include <vlGraphics/Actor.hpp>
    #include <vlGraphics/Effect.hpp>
    #include <vlCore/Time.hpp>
    #include <vlGraphics/Light.hpp>

    class App_RotatingCube: public vl::Applet
    {
    public:
      // called once after the OpenGL window has been opened
      void initEvent()
      {
        // allocate the Transform
        mCubeTransform = new vl::Transform;
        // bind the Transform with the transform tree of the rendring pipeline
        rendering()->as<vl::Rendering>()->transform()->addChild( mCubeTransform.get() );

        // create the cube's Geometry and compute its normals to support lighting
        vl::ref<vl::Geometry> cube = vl::makeBox( vl::vec3(0,0,0), 10, 10, 10 );
        cube->computeNormals();

        // setup the effect to be used to render the cube
        vl::ref<vl::Effect> effect = new vl::Effect;
        // enable depth test and lighting
        effect->shader()->enable(vl::EN_DEPTH_TEST);
        // add a Light to the scene, since no Transform is associated to the Light it will follow the camera
        effect->shader()->setRenderState( new vl::Light, 0 );
        // enable the standard OpenGL lighting
        effect->shader()->enable(vl::EN_LIGHTING);
        // set the front and back material color of the cube
        // "gocMaterial" stands for "get-or-create Material"
        effect->shader()->gocMaterial()->setDiffuse( vl::crimson );

        // install our scene manager, we use the SceneManagerActorTree which is the most generic
        vl::ref<vl::SceneManagerActorTree> scene_manager = new vl::SceneManagerActorTree;
        rendering()->as<vl::Rendering>()->sceneManagers()->push_back(scene_manager.get());
        // add the cube to the scene using the previously defined effect and transform
        scene_manager->tree()->addActor( cube.get(), effect.get(), mCubeTransform.get()  );
      }

      // called every frame
      virtual void updateScene()
      {
        // rotates the cube around the Y axis 45 degrees per second
        vl::real degrees = vl::Time::currentTime() * 45.0f;
        vl::mat4 matrix = vl::mat4::getRotation( degrees, 0,1,0 );
        mCubeTransform->setLocalMatrix( matrix );
      }

    protected:
      vl::ref<vl::Transform> mCubeTransform;
    };
    // Have fun!

Using the Qt4 Utility Bindings

Complete source: `src/examples/Qt4_example.cpp`

    #include <vlCore/VisualizationLibrary.hpp>
    #include <vlQt4/Qt4Widget.hpp>
    #include "Applets/App_RotatingCube.hpp"

    using namespace vl;
    using namespace vlQt4;

    int main(int argc, char *argv[])
    {
      QApplication app(argc, argv);

      /* init Visualization Library */
      VisualizationLibrary::init();

      /* setup the OpenGL context format */
      OpenGLContextFormat format;
      format.setDoubleBuffer(true);
      format.setRGBABits( 8,8,8,8 );
      format.setDepthBufferBits(24);
      format.setStencilBufferBits(8);
      format.setFullscreen(false);
      //format.setMultisampleSamples(16);
      //format.setMultisample(true);

      /* create the applet to be run */
      ref<Applet> applet = new App_RotatingCube;
      applet->initialize();
      /* create a native Qt4 window */
      ref<vlQt4::Qt4Widget> qt4_window = new vlQt4::Qt4Widget;
      /* bind the applet so it receives all the GUI events related to the OpenGLContext */
      qt4_window->addEventListener(applet.get());
      /* target the window so we can render on it */
      applet->rendering()->as<Rendering>()->renderer()->setFramebuffer( qt4_window->framebuffer() );
      /* black background */
      applet->rendering()->as<Rendering>()->camera()->viewport()->setClearColor( black );
      /* define the camera position and orientation */
      vec3 eye    = vec3(0,10,35); // camera position
      vec3 center = vec3(0,0,0);   // point the camera is looking at
      vec3 up     = vec3(0,1,0);   // up direction
      mat4 view_mat = mat4::getLookAt(eye, center, up);
      applet->rendering()->as<Rendering>()->camera()->setViewMatrix( view_mat );
      /* Initialize the OpenGL context and window properties */
      int x = 10;
      int y = 10;
      int width = 512;
      int height= 512;
      qt4_window->initQt4Widget( "Visualization Library on Qt4 - Rotating Cube", format, NULL, x, y, width, height );
      /* show the window */
      qt4_window->show();

      /* run the Win32 message loop */
      int val = app.exec();

      /* deallocate the window with all the OpenGL resources before shutting down Visualization Library */
      qt4_window = NULL;

      /* shutdown Visualization Library */
      VisualizationLibrary::shutdown();

      return val;
    }
    // Have fun!

Using the wxWidgets Utility Bindings

Complete source: `src/examples/WX_example.cpp`

    #include <vlWX/WXGLCanvas.hpp>
    #include <vlCore/VisualizationLibrary.hpp>
    #include "Applets/App_RotatingCube.hpp"

    using namespace vlWX;
    using namespace vl;

    //-----------------------------------------------------------------------------
    // main window
    //-----------------------------------------------------------------------------
    class MyFrame: public wxFrame
    {
    public:
      MyFrame(wxWindow *parent, const wxString& title, const wxPoint& pos, const wxSize& size, long style = wxDEFAULT_FRAME_STYLE):
        wxFrame(parent, wxID_ANY, title, pos, size, style) {}
      ~MyFrame(){}
    };
    //-----------------------------------------------------------------------------
    // implement the application
    //-----------------------------------------------------------------------------
    class MyApp: public wxApp
    {
    public:
      bool OnInit();
      int OnExit();
    };
    //-----------------------------------------------------------------------------
    IMPLEMENT_APP(MyApp)
    //-----------------------------------------------------------------------------
    bool MyApp::OnInit()
    {
      /* open a console so we can see the applet's output on stdout */
      showWin32Console();

      /* init Visualization Library */
      VisualizationLibrary::init();

      MyFrame *frame = new MyFrame(NULL, L"WXGLCanvas", wxDefaultPosition, wxSize(400, 300));

      /* Initialize the OpenGL context and window properties */
      // WX_GL_RGBA:            Use true colour
      // WX_GL_BUFFER_SIZE:     Bits for buffer if not WX_GL_RGBA
      // WX_GL_LEVEL:           0 for main buffer, >0 for overlay, <0 for underlay
      // WX_GL_DOUBLEBUFFER:    Use doublebuffer
      // WX_GL_STEREO:          Use stereoscopic display
      // WX_GL_AUX_BUFFERS:     Number of auxiliary buffers (not all implementation support this option)
      // WX_GL_MIN_RED:         Use red buffer with most bits (> MIN_RED bits)
      // WX_GL_MIN_GREEN:       Use green buffer with most bits (> MIN_GREEN bits)
      // WX_GL_MIN_BLUE:        Use blue buffer with most bits (> MIN_BLUE bits)
      // WX_GL_MIN_ALPHA:       Use alpha buffer with most bits (> MIN_ALPHA bits)
      // WX_GL_DEPTH_SIZE:      Bits for Z-buffer (0,16,32)
      // WX_GL_STENCIL_SIZE:    Bits for stencil buffer
      // WX_GL_MIN_ACCUM_RED:   Use red accum buffer with most bits (> MIN_ACCUM_RED bits)
      // WX_GL_MIN_ACCUM_GREEN: Use green buffer with most bits (> MIN_ACCUM_GREEN bits)
      // WX_GL_MIN_ACCUM_BLUE:  Use blue buffer with most bits (> MIN_ACCUM_BLUE bits)
      // WX_GL_MIN_ACCUM_ALPHA: Use blue buffer with most bits (> MIN_ACCUM_ALPHA bits)
      int context_format[] =
      {
        WX_GL_RGBA,
        WX_GL_DOUBLEBUFFER,
        WX_GL_MIN_RED, 8,
        WX_GL_MIN_GREEN, 8,
        WX_GL_MIN_BLUE, 8,
        WX_GL_MIN_ALPHA, 8,
        WX_GL_DEPTH_SIZE, 24,
        WX_GL_STENCIL_SIZE, 8,
        /*WX_GL_LEVEL, 0,
        WX_GL_AUX_BUFFERS, 0*/
        0
      };
      ref<WXGLCanvas> vl_gl_canvas = new WXGLCanvas( frame, NULL, wxID_ANY, wxDefaultPosition, wxDefaultSize, wxFULL_REPAINT_ON_RESIZE, context_format );

      /* create the applet to be run */
      ref<Applet> applet = new App_RotatingCube;

      applet->initialize();

      /* target the window so we can render on it */
      applet->rendering()->as<Rendering>()->renderer()->setFramebuffer( vl_gl_canvas->framebuffer() );

      /* black background */
      applet->rendering()->as<Rendering>()->camera()->viewport()->setClearColor( black );

      /* define the camera position and orientation */
      vec3 eye    = vec3(0,10,35); // camera position
      vec3 center = vec3(0,0,0);   // point the camera is looking at
      vec3 up     = vec3(0,1,0);   // up direction
      mat4 view_mat = mat4::getLookAt(eye, center, up);
      applet->rendering()->as<Rendering>()->camera()->setViewMatrix( view_mat );

      /* show the window */
      frame->Show();

      /* THE ORDER IS IMPORTANT IMPORTANT */
      vl_gl_canvas->initGLContext();

      /* bind the applet so it receives all the GUI events related to the OpenGLContext */
      vl_gl_canvas->addEventListener(applet.get());

      /* these must be done after the window is visible */
      int x = 0;
      int y = 0;
      int width = 512;
      int height= 512;
      frame->SetPosition( wxPoint(x,y) );
      frame->SetClientSize( wxSize(width,height) );
      frame->SetLabel(wxT("Visualization Library on wxWindows - Rotating Cube"));

      return true;
    }
    //-----------------------------------------------------------------------------
    int MyApp::OnExit()
    {
      VisualizationLibrary::shutdown();
      return 0;
    }
    //-----------------------------------------------------------------------------
    // Have fun!

Using the Win32 Utility Bindings

Complete source: `src/examples/Win32_example.cpp`

    #include <vlCore/VisualizationLibrary.hpp>
    #include <vlWin32/Win32Window.hpp>
    #include "Applets/App_RotatingCube.hpp"

    using namespace vl;
    using namespace vlWin32;

    int APIENTRY WinMain(HINSTANCE /*hCurrentInst*/, HINSTANCE /*hPreviousInst*/, LPSTR /*lpszCmdLine*/, int /*nCmdShow*/)
    {
      /* open a console so we can see the applet's output on stdout */
      showWin32Console();

      /* init Visualization Library */
      VisualizationLibrary::init();

      /* setup the OpenGL context format */
      OpenGLContextFormat format;
      format.setDoubleBuffer(true);
      format.setRGBABits( 8,8,8,0 );
      format.setDepthBufferBits(24);
      format.setStencilBufferBits(8);
      format.setFullscreen(false);
      format.setMultisampleSamples(16);
      format.setMultisample(false);

      /* create the applet to be run */
      ref<Applet> applet = new App_RotatingCube;
      applet->initialize();

      /* create a native Win32 window */
      ref<vlWin32::Win32Window> win32_window = new vlWin32::Win32Window;

      /* bind the applet so it receives all the GUI events related to the OpenGLContext */
      win32_window->addEventListener(applet.get());

      /* target the window so we can render on it */
      applet->rendering()->as<Rendering>()->renderer()->setFramebuffer( win32_window->framebuffer() );

      /* black background */
      applet->rendering()->as<Rendering>()->camera()->viewport()->setClearColor( black );

      /* define the camera position and orientation */
      vec3 eye    = vec3(0,10,35); // camera position
      vec3 center = vec3(0,0,0);   // point the camera is looking at
      vec3 up     = vec3(0,1,0);   // up direction
      mat4 view_mat = mat4::getLookAt(eye, center, up);
      applet->rendering()->as<Rendering>()->camera()->setViewMatrix( view_mat );

      /* Initialize the OpenGL context and window properties */
      int x = 0;
      int y = 0;
      int width = 512;
      int height= 512;
      win32_window->initWin32GLWindow(NULL, NULL, "Visualization Library on Win32 - Rotating Cube", format, x, y, width, height );

      /* show the window */
      win32_window->show();

      /* run the Win32 message loop */
      int res = vlWin32::messageLoop();

      /* deallocate the window with all the OpenGL resources before shutting down Visualization Library */
      win32_window = NULL;

      /* shutdown Visualization Library */
      VisualizationLibrary::shutdown();

      return res;
    }
    // Have fun!

Using the MFC Utility Bindings

Complete source: `src/examples/MFC_example/MFC_example.cpp`

    #include "StdAfx.h"
    #include <vlCore/VisualizationLibrary.hpp>
    #include <vlMFC/MFCWindow.hpp>
    #include "Applets/App_RotatingCube.hpp"

    using namespace vl;
    using namespace vlMFC;

    /* MFC_Example: implements the MFC application */
    class MFC_Example: public CWinApp
    {
    public:
      MFC_Example() {}

      virtual BOOL InitInstance();
      virtual int ExitInstance();
      /*virtual int Run();*/
      virtual BOOL OnIdle(LONG lCount);

    protected:
      ref<MFCWindow> mVLCWin;

      DECLARE_MESSAGE_MAP ()
    };
    BEGIN_MESSAGE_MAP(MFC_Example, CWinApp)
    END_MESSAGE_MAP()

    /* instance of the MFC application */
    MFC_Example mfc_app;

    /* updates the GL window */
    BOOL MFC_Example::OnIdle(LONG lCount)
    {
      if( mVLCWin->continuousUpdate() )
        mVLCWin->Win32Context::update();
      else
        Sleep(1);
      return TRUE;
    }

    /* called when the application exits */
    int MFC_Example::ExitInstance()
    {
      CWinApp::ExitInstance();

      /* destroy the window and the OpenGL rendering context */
      mVLCWin = NULL;

      /* shutdown Visualization Library */
      VisualizationLibrary::shutdown();

      return 0;
    }

    /* called when the application starts */
    BOOL MFC_Example::InitInstance()
    {
      CWinApp::InitInstance();

      /* open a console so we can see the program's output on stdout */
      showWin32Console();

      /* init Visualization Library */
      VisualizationLibrary::init();

      /* setup the OpenGL context format */
      OpenGLContextFormat format;
      format.setDoubleBuffer(true);
      format.setRGBABits( 8,8,8,0 );
      format.setDepthBufferBits(24);
      format.setStencilBufferBits(8);
      format.setFullscreen(false);
      format.setMultisampleSamples(16);
      format.setMultisample(true);

      /* create the applet to be run */
      ref<Applet> applet = new App_RotatingCube;
      applet->initialize();
      /* instance the MFC window/OpenGLContext */
      mVLCWin = new MFCWindow;
      /* bind the applet so it receives all the GUI events related to the OpenGLContext */
      mVLCWin->addEventListener(applet.get());
      /* target the window so we can render on it */
      applet->rendering()->as<Rendering>()->renderer()->setFramebuffer( mVLCWin->framebuffer() );
      /* black background */
      applet->rendering()->as<Rendering>()->camera()->viewport()->setClearColor( black );
      /* define the camera position and orientation */
      vec3 eye    = vec3(0,10,35); // camera position
      vec3 center = vec3(0,0,0);   // point the camera is looking at
      vec3 up     = vec3(0,1,0);   // up direction
      mat4 view_mat = mat4::getLookAt(eye, center, up);
      applet->rendering()->as<Rendering>()->camera()->setViewMatrix( view_mat );
      /* Initialize the OpenGL context and window properties */
      int x = 100;
      int y = 100;
      int width = 512;
      int height= 512;
      mVLCWin->initMFCWindow(NULL, NULL, "Visualization Library on MFC - Rotating Cube", format, x, y, width, height);

      /* MFC specific stuff */
      m_pMainWnd = mVLCWin.get();
      m_pMainWnd->ShowWindow(m_nCmdShow);
      m_pMainWnd->UpdateWindow();

      return TRUE;
    }
    // Have fun!

Using the SDL GUI Utility Bindings

Complete source: `src/examples/SDL_example.cpp`

    #include <vlCore/VisualizationLibrary.hpp>
    #include <vlSDL/SDLWindow.hpp>
    #include "Applets/App_RotatingCube.hpp"

    using namespace vl;

    int main(int argc, char* args[])
    {
      /* init Visualization Library */
      VisualizationLibrary::init();

      /* setup the OpenGL context format */
      OpenGLContextFormat format;
      format.setDoubleBuffer(true);
      format.setRGBABits( 8,8,8,8 );
      format.setDepthBufferBits(24);
      format.setStencilBufferBits(8);
      format.setFullscreen(false);
      //format.setMultisampleSamples(16);
      //format.setMultisample(true);

      /* create the applet to be run */
      ref<Applet> applet = new App_RotatingCube;
      applet->initialize();
      /* create a native SDL window */
      ref<vlSDL::SDLWindow> sdl_window = new vlSDL::SDLWindow;
      /* bind the applet so it receives all the GUI events related to the OpenGLContext */
      sdl_window->addEventListener(applet.get());
      /* target the window so we can render on it */
      applet->rendering()->as<Rendering>()->renderer()->setFramebuffer( sdl_window->framebuffer() );
      /* black background */
      applet->rendering()->as<Rendering>()->camera()->viewport()->setClearColor( black );
      /* define the camera position and orientation */
      vec3 eye    = vec3(0,10,35); // camera position
      vec3 center = vec3(0,0,0);   // point the camera is looking at
      vec3 up     = vec3(0,1,0);   // up direction
      mat4 view_mat = mat4::getLookAt(eye, center, up);
      applet->rendering()->as<Rendering>()->camera()->setViewMatrix( view_mat );
      /* Initialize the OpenGL context and window properties */
      int x = 0;
      int y = 0;
      int width = 512;
      int height= 512;
      sdl_window->initSDLWindow( "Visualization Library on SDL - Rotating Cube", format, x, y, width, height );

      /* run SDL message loop */
      vlSDL::messageLoop();

      /* deallocate the window with all the OpenGL resources before shutting down Visualization Library */
      sdl_window = NULL;

      /* shutdown Visualization Library */
      VisualizationLibrary::shutdown();

      return 0;
    }
    // Have fun!

Using the GLUT GUI Utility Bindings

Complete source: `src/examples/GLUT_example.cpp`

    #include <vlCore/VisualizationLibrary.hpp>
    #include <vlGLUT/GLUTWindow.hpp>
    #include "Applets/App_RotatingCube.hpp"

    using namespace vl;

    int main ( int argc, char *argv[] )
    {
      /* init GLUT */
      int pargc = argc;
      glutInit( &pargc, argv );

      /* init Visualization Library */
      VisualizationLibrary::init();

      /* install Visualization Library shutdown function */
      atexit( vlGLUT::atexit_visualization_library_shutdown );

      /* setup the OpenGL context format */
      OpenGLContextFormat format;
      format.setDoubleBuffer(true);
      format.setRGBABits( 8,8,8,8 );
      format.setDepthBufferBits(24);
      format.setStencilBufferBits(8);
      format.setFullscreen(false);
      //format.setMultisampleSamples(16);
      //format.setMultisample(true);

      /* create the applet to be run */
      ref<Applet> applet = new App_RotatingCube;
      applet->initialize();
      /* create a native GLUT window */
      ref<vlGLUT::GLUTWindow> glut_window = new vlGLUT::GLUTWindow;
      /* bind the applet so it receives all the GUI events related to the OpenGLContext */
      glut_window->addEventListener(applet.get());
      /* target the window so we can render on it */
      applet->rendering()->as<Rendering>()->renderer()->setFramebuffer( glut_window->framebuffer() );
      /* black background */
      applet->rendering()->as<Rendering>()->camera()->viewport()->setClearColor( black );
      /* define the camera position and orientation */
      vec3 eye    = vec3(0,10,35); // camera position
      vec3 center = vec3(0,0,0);   // point the camera is looking at
      vec3 up     = vec3(0,1,0);   // up direction
      mat4 view_mat = mat4::getLookAt(eye, center, up);
      applet->rendering()->as<Rendering>()->camera()->setViewMatrix( view_mat );
      /* Initialize the OpenGL context and window properties */
      int x = 0;
      int y = 0;
      int width = 512;
      int height= 512;
      glut_window->initGLUTWindow( "Visualization Library on GLUT - Rotating Cube", format, x, y, width, height );

      /* ... you can open more than one GLUT window! */

      /* enter the GLUT main loop */
      glutMainLoop();

      /* this point is never reached since glutMainLoop() never returns! */

      return 0;
    }
    // Have fun!

Visualization Library v2011.09.1162 Reference Documentation
Copyright 2005-2011 Michele Bosi. All rights reserved.
Updated on Thu Jan 26 2012 00:43:57.
Permission is granted to use this page to write and publish articles regarding Visualization Library.