simpleGLGraphicsScene.cc

/*===========================================================================*\
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//=============================================================================
//
//  CLASS SimpleGLGraphicsScene - IMPLEMENTATION
//
//=============================================================================

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

#include <ACG/GL/acg_glew.hh>
#include <OpenFlipper/common/GlobalOptions.hh>
#include <OpenFlipper/BasePlugin/PluginFunctions.hh>
#include <OpenFlipper/widgets/glWidget/QtBaseViewer.hh>
#include <QApplication>
#include <QPainter>
#include <QPaintEngine>
#include <QGraphicsSceneMouseEvent>

#include "simpleGLGraphicsScene.hh"

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

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

SimpleGLGraphicsScene::SimpleGLGraphicsScene () :
  QGraphicsScene (),
  view_(),
  initialized_(false)
{
  cursorPainter_ = new CursorPainter (this);
  cursorPainter_->setEnabled( OpenFlipperSettings().value("Core/Gui/glViewer/nativeMouse",false).toBool() );
}


void SimpleGLGraphicsScene::drawBackground(QPainter *_painter, const QRectF &_rect)
{
  
  // Check for switch in qt4.6 to OpenGL2
  if (_painter->paintEngine()->type() != QPaintEngine::OpenGL && _painter->paintEngine()->type() != QPaintEngine::OpenGL2 ) {
    std::cerr << "QtGLGraphicsScene: drawBackground needs a QGLWidget to be set as viewport on the graphics view\n";
    return;
  }
  
  // Initialize background first
  _painter->setBackground(QApplication::palette().window());
  _painter->eraseRect(_rect);

  if (!view_)
    return;
  
  // From now on we do OpenGL direct painting on the scene
  // Tell Qt that we directly use OpenGL
  _painter->beginNativePainting();

  if (!initialized_)
  {
    // we use GLEW to manage extensions
    // initialize it first
    #ifndef __APPLE__
    glewInit();
    #endif
    view_->initializeGL();
    cursorPainter_->initializeGL ();
    initialized_ = true;
  }

  if (cursorPainter_->enabled())
  {
    // avoid projection matrix stack overflow
    GLdouble mat[16];
    glGetDoublev(GL_PROJECTION_MATRIX, mat);

    glMatrixMode(GL_MODELVIEW);
    glPushMatrix ();

    glPushAttrib (GL_ALL_ATTRIB_BITS);
    view_->updateCursorPosition(cursorPainter_->cursorPosition ());
    glPopAttrib ();

    glMatrixMode(GL_PROJECTION);
    glLoadMatrixd (mat);
    glMatrixMode(GL_MODELVIEW);
    glPopMatrix ();
    glClear(GL_DEPTH_BUFFER_BIT);
  }
  
  // Clear the depth buffer (This is required since QT4.6 Otherwise we get an emtpty scene!
  glClear(GL_DEPTH_BUFFER_BIT);

  view_->paintGL();
  
  // The rest is painting through QT again. 
  _painter->endNativePainting();
}


void SimpleGLGraphicsScene::mouseMoveEvent(QGraphicsSceneMouseEvent* _e)
{
  QGraphicsScene::mouseMoveEvent(_e);
  if (_e->isAccepted())
    return;

  if (view_)
    view_->mouseMoveEvent(_e);
}

void SimpleGLGraphicsScene::setView(glViewer * _view)
{
  view_ = _view;
  cursorPainter_->registerViewer (view_);
}

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

bool SimpleGLGraphicsScene::event(QEvent *_event)
{
  if (_event->type() == QEvent::Enter)
  {
    cursorPainter_->setMouseIn (true);
  }
  else if (_event->type() == QEvent::Leave)
  {
    cursorPainter_->setMouseIn (false);
    update ();
  }
  else if (cursorPainter_ && _event->type() == QEvent::GraphicsSceneMouseMove)
  {
    QGraphicsSceneMouseEvent *e = static_cast<QGraphicsSceneMouseEvent*>(_event);
    cursorPainter_->updateCursorPosition (e->scenePos ());
    update ();
  }
  return QGraphicsScene::event (_event);
}

//=============================================================================
//=============================================================================