C64Lib.Core.C64.VBlank C# (CSharp) Method

        public void VBlank(bool draw_frame)
        {
            TheDisplay.PollKeyboard(TheCIA1.KeyMatrix, TheCIA1.RevMatrix, ref joykey);

            if (TheDisplay.QuitRequested)
            {
                quit_thyself = true;
            }

            // Poll the joysticks.
            TheCIA1.Joystick1 = poll_joystick(0);
            TheCIA1.Joystick2 = poll_joystick(1);

            if (GlobalPrefs.ThePrefs.JoystickSwap)
            {
                byte tmp = TheCIA1.Joystick1;
                TheCIA1.Joystick1 = TheCIA1.Joystick2;
                TheCIA1.Joystick2 = tmp;
            }

            // Joystick keyboard emulation.
            if (TheDisplay.SwapJoysticks)
                TheCIA1.Joystick1 &= joykey;
            else
                TheCIA1.Joystick2 &= joykey;

            // Count TOD clocks.
            TheCIA1.CountTOD();
            TheCIA2.CountTOD();

            // Output a frag.
               //     TheSID.VBlank();

            if (have_a_break)
            {
                return;
            }

            // Update the window if needed.
            frame++;

            if (draw_frame)
            {
                // Perform the actual screen update exactly at the
                // beginning of an interval for the smoothest video.
                TheDisplay.Update();

                frameTimer.Stop();

                // Compute the speed index and show it in the speedometer.
                double elapsed_time = (double)frameTimer.ElapsedMicroseconds;
                double speed_index = 20000.0 / elapsed_time * 100.0;

                //System.Diagnostics.Debug.WriteLine(speed_index);

                // Limit speed to 100% if desired
                /*
                if ((speed_index > 100.0) && GlobalPrefs.ThePrefs.LimitSpeed)
                {
                    int sleeptime = (int)((20000 - elapsed_time) / 1000.0);
                    Thread.Sleep(sleeptime);
                    speed_index = 100.0;
                }
                */

                emulationSpeed = emulationSpeed * 0.99f + ((float) speed_index) * 0.01f;

                frameTimer.Reset();
                frameTimer.Start();

            }
        }