QtBaseViewer.cc

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//=============================================================================
//
//  CLASS glViewer - IMPLEMENTATION
//
//=============================================================================


//== INCLUDES =================================================================

#include <ACG/GL/acg_glew.hh>

#include "QtBaseViewer.hh"
#include "QtGLViewerLayout.hh"
#include "PostProcessing.hh"

#include <ACG/QtWidgets/QtWheel.hh>
#include <ACG/Scenegraph/CoordsysNode.hh>
#include <ACG/Scenegraph/SceneGraphAnalysis.hh>
#include <ACG/Scenegraph/StencilRefNode.hh>
#include <ACG/GL/GLError.hh>
#include <ACG/GL/IRenderer.hh>

#include <QGraphicsWidget>
#include <QString>
#include <QBoxLayout>
#include <QtNetwork/QUdpSocket>
#include <QToolBar>
#include <QGraphicsSceneDragDropEvent>
#include <QPropertyAnimation>

#include <QMimeData>

#include <QClipboard>
#include <QApplication>
#include <QSplitter>
#include <QColorDialog>

#include <QGraphicsView>
#include <QGraphicsProxyWidget>

#include <QImageWriter>


#include <QOpenGLFramebufferObject>

#ifdef max
#  undef max
#endif

#ifdef min
#  undef min
#endif

#include <OpenFlipper/BasePlugin/PluginFunctions.hh>
#include <OpenFlipper/common/ViewObjectMarker.hh>

#include <OpenFlipper/common/GlobalOptions.hh>

#include <OpenFlipper/common/RendererInfo.hh>
#include <QOpenGLWidget>

//== NAMESPACES ===============================================================



//== IMPLEMENTATION ==========================================================

static const char          COPY_PASTE_VIEW_START_STRING[] =
  "ACG::QtWidgets::QGLViewerWidget encoded view";

//== IMPLEMENTATION ==========================================================


glViewer::glViewer( QGraphicsScene* _scene,
                    OFGLWidget* _glWidget,
                    Viewer::ViewerProperties& _properties,
                    QGraphicsWidget* _parent) :
  QGraphicsWidget(_parent),
  glareaGrabbed_(false),
  projectionUpdateLocked_(false),
  glScene_(_scene),
  glWidget_(_glWidget),
  glDebugLogger_(0),
  pickCache_(0),
  mouseCache_(nullptr),
  updatePickCache_(true),
  pickCacheSupported_(true),
  constrainedRotationAxis_(std::numeric_limits<double>::quiet_NaN(), 0, 0),
  clickEvent_(QEvent::MouseButtonPress, QPoint (), Qt::NoButton, Qt::NoButton, Qt::NoModifier),
  properties_(_properties),
  glstate_(0),
  initialized_(false),
  flyAnimationPerspective_(0),
  flyAnimationOrthogonal_(0),
  flyAngle_(0.0),
  currentAnimationPos_(0.0),
  flyMoveBack_(false),
  postproc_(0)
{

  // widget stuff
  createWidgets();

  // bind GL context to GL state class
  glstate_ = new ACG::GLState(true, _glWidget->format().profile() != OFGLFormat::CoreProfile);

  properties_.setglState( glstate_ );

  // state
  isRotating_       = false;
  lookAround_       = false;

  sceneGraphRoot_   = 0;

  normalsMode_      = NORMALIZE_NORMALS;
  projectionMode_   = PERSPECTIVE_PROJECTION;
  navigationMode_   = NORMAL_NAVIGATION;

  trackMouse_ = false;

  // Note: we start locked (initialization of updateLocked_)
  // will be unlocked in initializeGL()

  QSizePolicy sp = sizePolicy();
  sp.setHorizontalPolicy( QSizePolicy::Expanding );
  sp.setVerticalPolicy( QSizePolicy::Expanding );
  sp.setHorizontalStretch( 1 );
  sp.setVerticalStretch( 1 );
  setSizePolicy( sp );

  redrawTime_.start();

  // timer for animation
  timer_ = new QTimer( this );
  connect( timer_, SIGNAL(timeout()), this, SLOT( slotAnimation()) );

  fovyModifier_ = 1.0;

  allowRotation_ = true;


  connect( &properties_,SIGNAL(updated()), this, SLOT( slotPropertiesUpdated() ) );


  //check for updated properties once
  slotPropertiesUpdated();

  setAcceptDrops(true);

  setHome();

  clickTimer_.setSingleShot (true);
  connect (&clickTimer_, SIGNAL(timeout ()), this, SLOT(slotClickTimeout ()));
}


//-----------------------------------------------------------------------------


glViewer::~glViewer()
{
  delete glstate_;

  deleteGLDebugLogger();
  if (mouseCache_ != nullptr)
      deleteQFBO(mouseCache_);
}


//-----------------------------------------------------------------------------


//QSizeF
//glViewer::sizeHint(Qt::SizeHint which, const QSizeF & constraint) const
//{
//  return QSizeF( 600, 600 );
//}

//-----------------------------------------------------------------------------


void glViewer::makeCurrent() {

  const GLuint prevFbo = ACG::GLState::getFramebufferDraw();
  const GLuint prevReadFbo = ACG::GLState::getFramebufferRead();


  // calling makeCurrent binds the default FBO when QOpenGLWidget is used
  makeWidgetCurrent();

  //restore the previously bound FBO, if it was not 0 as Qt Documentation says we shall not bind 0
  if(prevFbo != 0)
    ACG::GLState::bindFramebuffer(GL_DRAW_FRAMEBUFFER, prevFbo);
  if(prevReadFbo != 0)
      ACG::GLState::bindFramebuffer(GL_READ_FRAMEBUFFER, prevFbo);

}


//-----------------------------------------------------------------------------

void glViewer::sceneGraph(ACG::SceneGraph::BaseNode* _root,
                          unsigned int               _maxPasses,
                          ACG::Vec3d                 _bbmin,
                          ACG::Vec3d                 _bbmax,
                          const bool _resetTrackBall)
{
  sceneGraphRoot_ = _root;

  if (sceneGraphRoot_ )
  {

    // set max number of render pass
    glstate_->set_max_render_passes(_maxPasses);
    
    if ( ( _bbmin[0] > _bbmax[0] ) ||
         ( _bbmin[1] > _bbmax[1] ) ||
         ( _bbmin[2] > _bbmax[2] )   ) {
      
      // Invalid bounding box, try to recover
      setScenePos( properties_.sceneCenter() , properties_.sceneRadius(), _resetTrackBall );
    
      // Update bounding box to match the scene geometry after recovery
      _bbmin = ACG::Vec3d(-1.0,-1.0,-1.0);
      _bbmax = ACG::Vec3d( 1.0, 1.0, 1.0);
    } else {
      
      // For very small scenes, we set the scene radius to 0.1
      // otherwise we take the real radius
      if ( ( _bbmax - _bbmin ).max() < OpenFlipperSettings().value("Core/Gui/glViewer/minimalSceneSize",0.1).toDouble() )  {
        setScenePos( ( _bbmin + _bbmax )        * 0.5,
                     OpenFlipperSettings().value("Core/Gui/glViewer/minimalSceneSize",0.1).toDouble(),
                     _resetTrackBall);
                   
      } else {
        setScenePos( ( _bbmin + _bbmax )        * 0.5,
                     ( _bbmax - _bbmin ).norm() * 0.5,
                     _resetTrackBall); 
      }
                   
    }
                   
    // remember the new bounding box for the state
    glstate_->set_bounding_box(_bbmin,_bbmax);
    
  }
  

  updateGL();

  emit(signalSceneGraphChanged(sceneGraphRoot_));
}


//-----------------------------------------------------------------------------


void glViewer::trackMouse(bool _track)
{
  trackMouse_ = _track;
}


//-----------------------------------------------------------------------------

void glViewer::setCoordSysProjection(ProjectionMode _mode) {
  // Find coordsys node
  ACG::SceneGraph::BaseNode* node = 0;
  node = PluginFunctions::getSceneGraphRootNode()->find("Core Coordsys Node");

  // set the projection mode for the coordinate system node
  if (node != 0) {
    ACG::SceneGraph::CoordsysNode* cnode = dynamic_cast<ACG::SceneGraph::CoordsysNode*> (node);
    if (_mode ==  ORTHOGRAPHIC_PROJECTION) {
      cnode->setProjectionMode(ACG::SceneGraph::CoordsysNode::ORTHOGRAPHIC_PROJECTION);
    } else {
      cnode->setProjectionMode(ACG::SceneGraph::CoordsysNode::PERSPECTIVE_PROJECTION);
    }
  }
}


//-----------------------------------------------------------------------------


void glViewer::perspectiveProjection()
{
  projectionMode(PERSPECTIVE_PROJECTION);
  updateGL();
}


void glViewer::orthographicProjection()
{
  projectionMode(ORTHOGRAPHIC_PROJECTION);
  updateGL();
}


void glViewer::toggleProjectionMode()
{
  if (projectionMode_ == ORTHOGRAPHIC_PROJECTION)
    projectionMode(PERSPECTIVE_PROJECTION);
  else
    projectionMode(ORTHOGRAPHIC_PROJECTION);

  updateGL();
}


void glViewer::projectionMode(ProjectionMode _p)
{
  if ((projectionMode_ = _p) == ORTHOGRAPHIC_PROJECTION)
    emit projectionModeChanged( true );
  else
    emit projectionModeChanged( false );

  updateProjectionMatrix();

  setCoordSysProjection(_p);

  emit viewChanged();
}

void glViewer::toggleNavigationMode()
{
  if (navigationMode_ == NORMAL_NAVIGATION)
    navigationMode(FIRSTPERSON_NAVIGATION);
  else
    navigationMode(NORMAL_NAVIGATION);
}


void glViewer::navigationMode(NavigationMode _n)
{
  if ((navigationMode_ = _n) == NORMAL_NAVIGATION)
    emit navigationModeChanged( true );
  else
    emit navigationModeChanged( false );
}

void glViewer::setFOVY(double _fovy) {
    
  if(_fovy <= 0.0 || _fovy >= 180) {
    std::cerr << "Error: Minimum or maximum fovy angle exceeded!" << std::endl;
    return;
  }
  
  OpenFlipperSettings().setValue("Core/Projection/FOVY", _fovy);
  updateProjectionMatrix();
}

void glViewer::updateProjectionMatrix(double _aspect)
{
  if( projectionUpdateLocked_ )
    return;

  makeCurrent();

  glstate_->reset_projection();

  const double aspect = _aspect ? _aspect : this->aspect_ratio();
  // In stereo mode we have to use a perspective matrix
  if ( projectionMode_ == PERSPECTIVE_PROJECTION)
  {

    // Get fovy
    const double fovy = this->field_of_view_vertical();

    glstate_->perspective(fovy, (GLdouble) aspect,
                          near_plane(), far_plane());
  }
  else
  {

    glstate_->ortho( -ortho_width(), ortho_width(),
                     -ortho_width() / aspect, ortho_width() / aspect,
                     near_plane(), far_plane() );
  }

}


//-----------------------------------------------------------------------------


void glViewer::setScenePos(const ACG::Vec3d& _center, double _radius, const bool _resetTrackBall)
{
  if(_resetTrackBall) {
    properties_.trackballCenter(_center);
  }

  properties_.sceneCenter(_center);

  properties_.sceneRadius(_radius);
  properties_.trackballRadius(_radius);

  ACG::Vec3d c = glstate_->modelview().transform_point(properties_.sceneCenter());

  double nearPlane = std::max(0.0001f * properties_.sceneRadius(),  -(c[2] + properties_.sceneRadius()));
  double farPlane  = std::max(0.0002f * properties_.sceneRadius(),  -(c[2] - properties_.sceneRadius()));

   // Safety check, if near < 0
   if ( nearPlane <= 0.0 ) {
     std::cerr << "Error in BaseViewer drawScene, nearplane <= 0.0" << std::endl;
     nearPlane = 0.000000000000001;
   }

  // Safety check. Make sure that they are in the right order
  if ( nearPlane > farPlane ) {
    std::cerr << "Error in BaseViewer setScenePos, Nearplane > Farplane" << std::endl;
    std::swap(nearPlane,farPlane);
  }

  properties_.setPlanes(nearPlane,farPlane);

  updateProjectionMatrix();
  updateGL();

  emit viewChanged();
}


//----------------------------------------------------------------------------


void glViewer::viewingDirection( const ACG::Vec3d& _dir, const ACG::Vec3d& _up )
{
  // calc eye point for this direction
  ACG::Vec3d eye = properties_.sceneCenter() - _dir * ( 3.0 * properties_.sceneRadius());

  glstate_->reset_modelview();
  glstate_->lookAt((ACG::Vec3d)eye, (ACG::Vec3d)properties_.sceneCenter(), (ACG::Vec3d)_up);

  emit viewChanged();
}

//-----------------------------------------------------------------------------

void glViewer::lookAt(const ACG::Vec3d& _eye, const ACG::Vec3d& _center, const ACG::Vec3d& _up) {
    
    glstate_->reset_modelview();
    glstate_->lookAt(_eye, _center, _up);
    
    properties_.sceneCenter( _center );
    properties_.sceneRadius( (properties_.sceneCenter() - _eye).norm() );
    
    emit viewChanged();
}

//-----------------------------------------------------------------------------

void glViewer::normalsMode(NormalsMode _mode)
{
  if (glstate_->compatibilityProfile())
  {
    makeCurrent();

    switch (normalsMode_ = _mode)
    {
    case DONT_TOUCH_NORMALS:
      ACG::GLState::disable(GL_NORMALIZE);
      break;

    case NORMALIZE_NORMALS:
      ACG::GLState::enable(GL_NORMALIZE);
      break;
    }

    updateGL();
  }
}


//-----------------------------------------------------------------------------


void glViewer::updateGL()
{
  if (!properties_.updateLocked() && isVisible() )
  {
    updatePickCache_ = true;
    update();

    emit viewUpdated();
  }
}



//-----------------------------------------------------------------------------


void glViewer::drawScene(double _aspect)
{
  
  // Inside the glWidget rendering, the system should not send extra updates
  properties_.blockSignals(true);
  
  QElapsedTimer  timer;
  timer.start();

  // *****************************************************************
  // Adjust clipping planes
  // *****************************************************************
  // Far plane
  ACG::Vec3d c = glstate_->modelview().transform_point(properties_.sceneCenter());

  double nearPlane = std::max(0.0001f * properties_.sceneRadius(),  -(c[2] + properties_.sceneRadius()));
  double farPlane  = std::max(0.0002f * properties_.sceneRadius(),  -(c[2] - properties_.sceneRadius()));

  // Safety check, if near < 0
  if ( nearPlane <= 0.0 ) {
    std::cerr << "Error in BaseViewer drawScene, nearplane < 0" << std::endl;
    nearPlane = 0.000000000000001;
  }

  // Safety check. Make sure that they are in the right order
  if ( nearPlane > farPlane ) {
    std::cerr << "Error in BaseViewer drawScene, Nearplane > Farplane" << std::endl;
    std::swap(nearPlane,farPlane);
  }

  properties_.setPlanes(nearPlane,farPlane);

  updateProjectionMatrix(_aspect);

  // store time since last repaint in gl state and restart timer
  glstate_->set_msSinceLastRedraw (redrawTime_.restart ());

  makeCurrent();
  if(!glstate_->compatibilityProfile())
    defaultVAO_.bind();

  // draw mono or stereo
  // If stereo mode is selected, we have to provide multiple ways of rendering.

  // 1. Default internal pipeline : Directly to output buffer (no stereo support!)
  // 2. Non default : Non-stereo Directly to output buffer (no stereo support!)
  //
  //

//  if (OpenFlipper::Options::stereoMode () == OpenFlipper::Options::OpenGL && OpenFlipper::Options::glStereo ())
//  {
//    // Stereo      : Hardware support (OpenGL stereo : left and right buffer with offset eyes)
//
//    return;
//  }
//  else if (OpenFlipper::Options::stereoMode () == OpenFlipper::Options::AnaglyphCustom && customAnaglyphSupported_)
//  {
//    //Stereo      : No Hardware support (Left and right frame buffer with offset eyes)
//  } else {
//
//  }

  // save hardware backbuffer
  GLuint backbufferFbo = 0;
  GLuint backbufferTarget = 0;
  glGetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, (GLint*)&backbufferFbo);
  glGetIntegerv(GL_DRAW_BUFFER, (GLint*)&backbufferTarget);



  // Render plugins do not have to worry about using scissor test for clearing their viewports later on.
  glClearColor(properties_.backgroundColor()[0], properties_.backgroundColor()[1],
    properties_.backgroundColor()[2], properties_.backgroundColor()[3]);
  GLint curViewport[4];
  glGetIntegerv(GL_VIEWPORT, curViewport);
  glScissor(curViewport[0], curViewport[1], curViewport[2], curViewport[3]);
  glEnable(GL_SCISSOR_TEST);
  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  glDisable(GL_SCISSOR_TEST);



  // setup scene target fbo
  if (!postproc_)
    postproc_ = new PostProcessing();

  const int numPostProcessors = postProcessorManager().numActive(properties_.viewerId());

  bool stereoOpenGL = false;
  bool stereoAnaglyph = false;
  ACG::GLMatrixd projSave = glstate_->projection();
  ACG::GLMatrixd projLR[2];

  if (properties_.stereo()) {
    stereoOpenGL = OpenFlipper::Options::stereoMode () == OpenFlipper::Options::OpenGL && OpenFlipper::Options::glStereo ();
    stereoAnaglyph = !stereoOpenGL;
    computeProjStereo(glstate_->viewport_width(), glstate_->viewport_height(), properties_, projLR, projLR+1);
  }

  if (!stereoOpenGL && !stereoAnaglyph)
  {
    // setup render target fbo
    postproc_->setupScene(properties_.viewerId(), glstate_->viewport_width(), glstate_->viewport_height(),
      properties_.multisampling() ? 16 : 0, -1);
  }



  // Check if we use build in default renderer
  if ( renderManager().activeId( properties_.viewerId() ) == 0 ) {
    drawScene_mono();
  } else {
    RenderInterface* renderPlugin = renderManager().active( properties_.viewerId() )->plugin;

    // eventually set viewer id in IRenderer
    ACG::IRenderer* shaderRenderPlugin = dynamic_cast<ACG::IRenderer*>(renderPlugin);

    if (shaderRenderPlugin)
    {
      shaderRenderPlugin->setViewerID( properties_.viewerId() );
      shaderRenderPlugin->setCoreProfileMode( OpenFlipper::Options::coreProfile() );
    }

    if (stereoOpenGL || stereoAnaglyph) {
      // save current fbo
      GLuint backbufferFbo = 0;
      GLuint backbufferTarget = 0;
      glGetIntegerv(GL_DRAW_FRAMEBUFFER_BINDING, (GLint*)&backbufferFbo);
      glGetIntegerv(GL_DRAW_BUFFER, (GLint*)&backbufferTarget);

      // setup stereo rendering

      // left eye: fbo 0
      // right eye: fbo 1

      for (int eye = 0; eye < 2; ++eye) {
        glstate_->set_projection(projLR[eye]);
        if (stereoOpenGL && !numPostProcessors) {
          // render directly into back_left
          glDrawBuffer(eye ? GL_BACK_RIGHT : GL_BACK_LEFT);
          glEnable(GL_SCISSOR_TEST);
          glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
          glDisable(GL_SCISSOR_TEST);
        }
        else {
          postproc_->setupScene(properties_.viewerId(), glstate_->viewport_width(), glstate_->viewport_height(),
            properties_.multisampling() ? 16 : 0, eye);
        }

        renderPlugin->render(glstate_,properties_);
        drawCursor();
      }

      // restore projection
      glstate_->set_projection(projSave);

      // restore backbuffer
      glBindFramebuffer(GL_FRAMEBUFFER, backbufferFbo);
      glDrawBuffer(backbufferTarget);
    }
    else {
      renderPlugin->render(glstate_,properties_);
      drawCursor();
    }
  }
  checkGLError();

  // =================================================================================
  // Post-Processing pipeline


  postproc_->postProcess(properties_.viewerId(),
    glstate_,
    glstate_->modelview(),
    (stereoOpenGL || stereoAnaglyph) ? projLR[0] : glstate_->projection(),
    projLR[1],
    stereoOpenGL);

  if (stereoAnaglyph)
    postproc_->resolveStereoAnyglyph(properties_.viewerId());

  // =================================================================================
  glBindFramebuffer(GL_FRAMEBUFFER, backbufferFbo);
  glDrawBuffer(backbufferTarget);
  // unbind vbo for qt log window
  ACG::GLState::bindBuffer(GL_ARRAY_BUFFER, 0);
  ACG::GLState::activeTexture(GL_TEXTURE0);
  ACG::GLState::bindTexture(GL_TEXTURE_2D, 0);
//  fbo.release();
//
//  QRect blitRect(0,0,glstate_->viewport_width(),glstate_->viewport_height());
//
//  //
//  //QTime time;
//  //time.restart();
//  QGLFramebufferObject::blitFramebuffer( 0 , blitRect, &fbo, blitRect , GL_COLOR_BUFFER_BIT );
//  //std::cerr << "Elapsed for blit: " << time.elapsed() << std::endl;
  glFinish();

  frame_time_ = timer.elapsed();

  
  // Inside the glWidget rendering, the system should not send extra updates
  properties_.blockSignals(false);
}


//-----------------------------------------------------------------------------


void glViewer::drawScene_mono()
{
  if (sceneGraphRoot_) {
    ViewObjectMarker *oM = properties_.objectMarker();
    GLuint refBits = 0;
    QSet<GLuint> references;

    if (oM)
    {
      glClear (GL_STENCIL_BUFFER_BIT);
      ACG::GLState::enable (GL_STENCIL_TEST);
      glStencilOp (GL_KEEP, GL_KEEP, GL_ZERO);
      glStencilFunc (GL_ALWAYS, 0, ~0);

      for (PluginFunctions::ObjectIterator o_it(PluginFunctions::ALL_OBJECTS, DATA_ALL) ;
          o_it != PluginFunctions::objectsEnd(); ++o_it)
      {
        bool ok;
        GLuint ref;

        ok = oM->stencilRefForObject(*o_it, ref);

        if (ok)
        {
          o_it->stencilRefNode ()->setReference (ref);
          o_it->stencilRefNode ()->show ();
          refBits |= ref;
          references << ref;
        }
        else
          o_it->stencilRefNode ()->hide ();
      }
    }

    // First pass
    ACG::SceneGraph::DrawAction pass1( properties_.drawMode(), *glstate_ , false);
    ACG::SceneGraph::traverse_multipass(sceneGraphRoot_, pass1, *glstate_, properties_.drawMode() );

    // Second Pass for Blending operations
    ACG::SceneGraph::DrawAction pass2(properties_.drawMode(), *glstate_, true);
    ACG::SceneGraph::traverse_multipass(sceneGraphRoot_, pass2, *glstate_, properties_.drawMode());

    if (oM)
    {
      if (oM->type() == ViewObjectMarker::PerBit)
      {
        references.clear ();
        for (unsigned int i = 0; i < sizeof (GLuint) * 8; i++)
          if (refBits & (1 << i))
            references << (1 << i);
      }

      glPushAttrib(GL_ALL_ATTRIB_BITS);

      ACG::GLState::enable(GL_BLEND);
      ACG::GLState::disable(GL_DEPTH_TEST);

      if (glstate_->compatibilityProfile())
        ACG::GLState::disable(GL_LIGHTING);

      ACG::GLState::disable(GL_DITHER);

      int vp_l, vp_b, vp_w, vp_h;
      glstate_->get_viewport (vp_l, vp_b, vp_w, vp_h);

      glMatrixMode(GL_PROJECTION);
      glPushMatrix ();
      glLoadIdentity();
      glOrtho(0, vp_w, vp_h, 0, 0, 1.0);
      glMatrixMode(GL_MODELVIEW);
      glPushMatrix ();
      glLoadIdentity();

      glStencilOp (GL_KEEP, GL_KEEP, GL_KEEP);

      foreach (unsigned int ref, references)
      {
        bool ok;
        GLenum sfactor;
        GLenum dfactor;
        ACG::Vec4f color;
        unsigned int mask = ~0;

        if (oM->type() == ViewObjectMarker::PerBit)
        {
          ok = oM->blendForStencilRefBit (ref, sfactor, dfactor, color);
          mask = ref;
        }
        else
          ok = oM->blendForStencilRefNumber (ref, sfactor, dfactor, color);

        if (!ok)
          continue;

        glStencilFunc (GL_EQUAL, ref, mask);

        ACG::GLState::blendFunc (sfactor, dfactor);
        glColor4f (color[0], color [1], color [2], color[3]);

        glBegin (GL_QUADS);
        glVertex2i(0, 0);
        glVertex2i(0, vp_h);
        glVertex2i(vp_w, vp_h);
        glVertex2i(vp_w, 0);
        glEnd ();

      }

      glMatrixMode(GL_PROJECTION);
      glPopMatrix ();
      glMatrixMode(GL_MODELVIEW);
      glPopMatrix ();

      glPopAttrib ();
      ACG::GLState::disable (GL_STENCIL_TEST);
    }


  }

  drawCursor();

}


void glViewer::drawCursor()
{
  if (properties_.cursorPainter() && properties_.cursorPainter()->enabled () && properties_.cursorPositionValid() )
  {
    glstate_->push_modelview_matrix ();
    // reset view transformation
    glstate_->reset_modelview ();
    // translate cursor position to 0,0
    glstate_->translate ( properties_.cursorPoint3D() );
    // paint cursor
    properties_.cursorPainter()->paintCursor (glstate_);
    glstate_->pop_modelview_matrix ();
  }
}


void glViewer::setHome()
{
  home_modelview_          = glstate_->modelview();
  home_inverse_modelview_  = glstate_->inverse_modelview();
  homeOrthoWidth_          = properties_.orthoWidth();
  home_center_             = properties_.trackballCenter();
  home_radius_             = properties_.trackballRadius();
}


void glViewer::home()
{
  makeCurrent();
  glstate_->set_modelview(home_modelview_, home_inverse_modelview_);
  properties_.orthoWidth( homeOrthoWidth_ );
  properties_.trackballCenter( home_center_ );
  properties_.trackballRadius(home_radius_);
  updateProjectionMatrix();
  updateGL();

  emit viewChanged();

}

//-----------------------------------------------------------------------------

void glViewer::viewAll()
{
  makeCurrent();
  // update scene graph (get new bounding box and set projection right, including near and far plane)
  properties_.lockUpdate();

  unsigned int maxPases = 1;
  ACG::Vec3d bbmin,bbmax;
  // update scene bounding boxes
  ACG::SceneGraph::analyzeSceneGraph(PluginFunctions::getSceneGraphRootNode(),maxPases,bbmin,bbmax);

  // update scene properties (near, far plane, scene radius according to the computed bounding boxes)
  sceneGraph ( PluginFunctions::getSceneGraphRootNode(), maxPases,bbmin,bbmax,true);


  // update camera
  // move center (in camera coords) to origin and translate in -z dir
  translate(-(glstate_->modelview().transform_point(properties_.sceneCenter()))
            - ACG::Vec3d(0.0, 0.0, 3.0 * properties_.sceneRadius()));

  properties_.orthoWidth( 1.1 * properties_.sceneRadius() );
  double aspect = (double) glWidth() / (double) glHeight();
  if (aspect > 1.0)
    properties_.orthoWidth( aspect * properties_.orthoWidth() ) ;

  properties_.unLockUpdate();
  updateProjectionMatrix();
  updateGL();