Example 2.5. A UFO main loop

// main event loop
bool done = false;
while (!done) {
  // pumps events from the system event queue
  display.pumpEvents();
  // dispatchEvents returns true when a quit event was processed.
  done = display.dispatchEvents();

  if (!done) {
    // repaint the frame
    frame->repaint();
    // give other processes a chance
    tk.sleep(1);
  }
}

Example 2.6. A UFO main loop for custom windows

// main event loop
bool done = false;
while (!done) {
  // pump your own events
  // of course, you should only push events you have processed from the system
  display.pushKeyDown(&context, keyCode, unicodeChar);
  display.pushKeyUp(&context, keyCode, 0);
  display.pushMouseMove(&context, x, y);
  display.pushMouseButtonDown(&context, x, y, UMod::LeftButton);
  display.pushMouseButtonUp(&context, x, y, UMod::RightButton);
  display.pushMouseWheelDown(&context, x, y);
  display.pushMouseWheelUp(&context, x, y);
  
  // dispatchEvents returns true when a quit event was processed.
  done = display.dispatchEvents();

  if (!done) {
    // repaint the context
    context.repaint();
    // give other processes a chance
    tk.sleep(1);
  }
}