   Regarding choosing viewport drawing area
  Hi,I am a newbie to OpenGL and have some doubts of choosing drawing area when I am splitting my GL window into two areas.Let me explain it.I have an OpenGL widget which is to be devided into two parts. Let say, 80% of the widget(upper area) will be drawing 3D objects, for which all mouse functions like rotation, pan, zooming will work when mouse is inside that area. Remaining 20% of widget(lower area) will have only text.For that I have activated mouse movement function(in Qt's opengl module). If mouse's y coordinate is inside 80% of the widget area, all mouse functions will work, otherwise not.glViewport(0, 0.20*glheight, glwidth, glheight);if(mousecoordy > 0.80*glheight) activatemouse = 0else activatemouse = 1;Now my question is, how can I choose this area? Right now whatever I do, even text drawing, in paintGL function, it default drawn in 80% of the area. How can I switch to remaining 20% of the area?Is this the right way of doing it. Suggestions are welcome.Thanks.M   
  Set the viewport to the top 80% and draw your stuff that belongs there: glViewport(0, 0.2*glheight, glwidth, 0.8*glheight);Then set the viewport to the bottom 20% and draw that stuff:glViewport(0, 0, glwidth, 0.2*glheight);;  You may need to set glScissor along with glViewport to avoid overdrawing.   