widgets/glWidget/QtBaseViewer.cc

@@ -138,6 +138,7 @@ glViewer::glViewer( QGraphicsScene* _scene,
   glDebugLogger_(0),
 #endif
   pickCache_(0),
+  mouseCache_(nullptr),
   updatePickCache_(true),
   pickCacheSupported_(true),
   constrainedRotationAxis_(std::numeric_limits<double>::quiet_NaN(), 0, 0),
@@ -217,6 +218,8 @@ glViewer::~glViewer()
   delete glstate_;
 
   deleteGLDebugLogger();
+  if (mouseCache_ != nullptr)
+      deleteQFBO(mouseCache_);
 }
 
 
@@ -1563,12 +1566,31 @@ void glViewer::contextMenuEvent(QGraphicsSceneContextMenuEvent* _e)
 
 void glViewer::mousePressEvent(QGraphicsSceneMouseEvent* _e)
 {
+  makeCurrent();
   QPoint p (_e->scenePos().x(), _e->scenePos().y());
   QMouseEvent me(QEvent::MouseButtonPress ,p, _e->screenPos(), _e->button(),
                  _e->buttons(), _e->modifiers());
   _e->accept ();
 
   emit signalMakeActive();
+  const GLuint prevFBO = ACG::GLState::getFramebufferDraw();
+
+  //recreate FBO if gl area was resized
+  if (mouseCache_ != nullptr && QFBOResized(mouseCache_))
+  {
+      deleteQFBO(mouseCache_);
+      mouseCache_ = nullptr;
+  }
+
+  if (mouseCache_ == nullptr)
+  {
+      GLuint fboHandle;
+      int samples = 0;
+      createQFBO(mouseCache_, &fboHandle, glWidth() , glHeight(), &samples);
+  }
+
+  bindQFBO(mouseCache_);
+
   glScene_->update ();
 
   // right button pressed => popup menu (ignore here)
@@ -1608,6 +1630,8 @@ void glViewer::mousePressEvent(QGraphicsSceneMouseEvent* _e)
         break;
     }
   }
+  //restore old FBO
+  ACG::GLState::bindFramebuffer(GL_FRAMEBUFFER_EXT,prevFBO);
 }
 
 
@@ -1894,7 +1918,7 @@ void glViewer::handleNormalNavigation( QMouseEvent* _event ) {
   switch (_event->type()) {
 
     case QEvent::MouseButtonPress: {
-      
+
       // Get the depth at the current mouse position ( projected )
       // This is used to do the translation in world coordinates
       // As the scene is rendered, we can get the depth directly from the framebuffer.

widgets/glWidget/QtBaseViewer.hh

@@ -573,6 +573,8 @@ private:
 
   // wrapper to create QFramebufferObject returns true if QFBO is valid if samples is -1 the default samples are retrieved
   bool createQFBO(QOpenGLFramebufferObject*& _ptr, GLuint* _handle, int _width, int _height, int* _samples);
+  bool bindQFBO(QOpenGLFramebufferObject* _ptr);
+  bool QFBOResized(QOpenGLFramebufferObject* _ptr);
   void blitQFBO(QOpenGLFramebufferObject* _ptr1, const QRect& _size1, QOpenGLFramebufferObject* _ptr2, const QRect& _size2);
   void deleteQFBO(QOpenGLFramebufferObject* _ptr);
 
@@ -889,6 +891,7 @@ private:
 
     /// Framebuffer object that holds the pick cache
     QFramebufferObject* pickCache_;
+    QFramebufferObject* mouseCache_;
 
     /// Should the pick cache be updated
     bool updatePickCache_;

widgets/glWidget/QtBaseViewer_qt.cc

@@ -214,6 +214,20 @@ void glViewer::blitQFBO(QOpenGLFramebufferObject* _ptr1, const QRect& _size1, QO
 
 //-----------------------------------------------------------------------------
 
+bool glViewer::bindQFBO(QOpenGLFramebufferObject* _ptr)
+{
+    return _ptr->bind();
+}
+
+//-----------------------------------------------------------------------------
+
+bool glViewer::QFBOResized(QOpenGLFramebufferObject* _ptr1)
+{
+    return _ptr1->size() != QSize(glWidth(), glHeight());
+}
+
+//-----------------------------------------------------------------------------
+
 void glViewer::deleteQFBO(QOpenGLFramebufferObject* _ptr)
 {
   delete _ptr;