Hi everyone

I'm using QGraphicsView drawbackground() to draw my openGL texture

Qt Code: 
  1. void
  2. Gview::drawBackground(QPainter *painters, const QRectF &rect)
  3. {
  4.         if(isFirstImg){
  5.             glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
  6.             glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
  7.             glBindTexture( GL_TEXTURE_2D, texture[0] );
  8.             glTexImage2D(GL_TEXTURE_2D,
  9.                          0,
  10.                          GL_RGB,
  11.                          1920,
  12.                          1080,
  13.                          0,
  14.                          GL_RGB,
  15.                          GL_UNSIGNED_BYTE,
  16.                          m_rgbSrc );
  17.  
  18.  
  19.             isFirstImg = false;
  20.         }else
  21.         {
  22.             glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
  23.             glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
  24.             glBindTexture( GL_TEXTURE_2D, texture[0] );
  25.             glTexSubImage2D(GL_TEXTURE_2D,
  26.                             0,
  27.                             0,
  28.                             0,
  29.                             1920,
  30.                             1080,
  31.                             GL_RGB,
  32.                             GL_UNSIGNED_BYTE,
  33.                             m_rgbSrc);
  34.         }
  35.  
  36.         glViewport(0,0,(GLint)this->width(), (GLint)this->height());
  37.  
  38.         glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
  39.         glMatrixMode(GL_MODELVIEW);
  40.         glLoadIdentity();
  41.         glEnable(GL_TEXTURE_2D);
  42.         glBindTexture(GL_TEXTURE_2D, texture[0]);
  43.         glBegin(GL_QUADS);
  44.         {
  45.             glTexCoord2f(0.0f, 1.0f);glVertex2f(-1.0f, -1.0f);
  46.             glTexCoord2f(1.0f, 1.0f);glVertex2f( 1.0f, -1.0f);
  47.             glTexCoord2f(1.0f, 0.0f);glVertex2f( 1.0f,  1.0f);
  48.             glTexCoord2f(0.0f, 0.0f);glVertex2f(-1.0f,  1.0f);
  49.         }
  50.         glEnd();
  51.         glDisable(GL_TEXTURE_2D);
  52.         glFlush();
  53.         isUpdated = false;
  54.  
  55. }
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and I add some GUI in QGraphicsScene in QGraphicsView.

Qt Code: 
  1. m_scene = new QGraphicsScene();
  2.     m_view  = new Gview();
  3.     m_view->setViewportUpdateMode(
  4.                 QGraphicsView::BoundingRectViewportUpdate);
  5.  
  6.     m_view->setHorizontalScrollBarPolicy(  Qt::ScrollBarAlwaysOff );
  7.     m_view->setVerticalScrollBarPolicy ( Qt::ScrollBarAlwaysOff );
  8.     m_view->setViewport(new QGLWidget(QGLFormat(QGL::SampleBuffers)));
  9.     m_view->setGraphicsScene(m_scene);
  10.     m_view->setGeometry(50,50,300,300);
  11.     m_view->show();
  12.  
  13.     QDialog *dialog = new QDialog(0);
  14.     dialog->setWindowOpacity(0.5);
  15.     dialog->setLayout(new QVBoxLayout);
  16.     dialog->layout()->addWidget(new QLabel("Hello!"));
  17.     dialog->layout()->addWidget(new QPushButton("Ok", 0));
  18.     m_scene->addWidget(dialog, dialog->windowFlags());
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sometime the texture is fine, sometime it isn't.

the openGL texture usually disappear in my window and remain the QDialog, if I shut the QDialog window when the programe is running, the openGL texture will be appeared.

so what's the problem??



thanks you help.