renderText of QGLWidget not working

Hello!

I try to display some text in my QT/OpenGL application. I try to use the methond renderText... but instead of letters "squares" are drawn (you can see them on red on the top left corner of the attached screenshot). I hope you can help me.

The code I use is this:

Code:

---

void OGLFrame::paintGL_R(GLenum mode, int x, int y)
{
  GLint vp[4];
  bool select;
 
  glViewport(_vp[0], _vp[1],  _vp[2], _vp[3]);
 
  if(mode != GL_SELECT)
    {
      select = false;
 
      glRenderMode(GL_RENDER);
 
      glMatrixMode(GL_PROJECTION);
      glPushMatrix();
      glLoadIdentity();
    }
  else
    {
      select = true;
 
      glGetIntegerv(GL_VIEWPORT, vp);
 
      glRenderMode(GL_SELECT);
      glInitNames();
      glPushName(0);
 
      glMatrixMode(GL_PROJECTION);
      glPushMatrix();
      glLoadIdentity();
 
      gluPickMatrix((GLdouble) x, (GLdouble) y, 5.0, 5.0, vp);
    }
 
  gluPerspective(_fovy, _aspect, 0.01, 2*EXT);
 
  glMatrixMode( GL_MODELVIEW );
  glPushMatrix();
  glLoadIdentity();
 
  this->setCamera();
 
  _ph->drawObjects(select);
 
  this->drawBackGround();
 
  glColor4f(1.0, 0.0, 0.0, 1.0);
  this->renderText(100, 100, "Hola");
 
//        glMatrixMode(GL_PROJECTION);
//        glPushMatrix();
//        glLoadIdentity();
 
//        glMatrixMode(GL_MODELVIEW);
//        glPushMatrix();
//        glLoadIdentity();
 
//        renderText(100, 100, "Hola");
 
//        glMatrixMode(GL_MODELVIEW);
//        glPopMatrix();
//        glMatrixMode(GL_PROJECTION);
//        glPopMatrix();
 
 
  glMatrixMode(GL_MODELVIEW);
  glPopMatrix();
 
  glMatrixMode(GL_PROJECTION);
  glPopMatrix();
 
  glFlush();
  glFinish();
}

---

As you can see, I made different attempts, but I always get the same result.

Thanks for your help

Upgrading from qt 4.3.4 to 4.4.0 made it work.

Is it a bug of qt 4.3? or was I doing something wrong?

Hi,

I am facing similar issue after porting my code to Qt5 from Qt 4.8, instead of text square/rectangular blocks are displayed on QGLWidget.
Please let me know if u found reason for this issue. Text displayed fine with Qt 4.8.

Thanks.