Ejemplo n.º 1
0
        private void RunGameLoopInBackground()
        {
            try
            {
                int hertz          = 60;
                var second         = Stopwatch.Frequency;
                var shortFrame     = second / hertz;
                var longFrameCount = (int)(second % hertz);

                var  nextFrame   = Stopwatch.GetTimestamp();
                var  nextSecond  = nextFrame + second;
                int  frameIndex  = 0;
                bool wasPrepared = true;

                while (_running && _gameLoop.Running)
                {
                    var now = Stopwatch.GetTimestamp();

                    if (nextSecond <= now)
                    {
                        // TODO: Add metric reporting
                        nextSecond += second;
                    }

                    // Erase all the empty seconds (due to a long application pause).
                    while (nextSecond <= now)
                    {
                        nextSecond += second;
                    }

                    if (now < nextFrame)
                    {
                        if (wasPrepared)
                        {
                            // TODO: Pick the optimal sleep strat.
                            // https://randomascii.wordpress.com/2012/06/05/in-praise-of-idleness/
                            Thread.Sleep(1);
                        }
                        else
                        {
                            _gameLoop.PrepareScene();
                            wasPrepared = true;
                        }
                    }
                    else
                    {
                        _gameLoop.FrameUpdate();
                        wasPrepared = false;

                        // Stretch the leftover sub-frame across all the other frames.
                        nextFrame += shortFrame + Convert.ToInt64(frameIndex < longFrameCount);
                        frameIndex = (frameIndex + 1) % hertz;
                    }
                }

                _gameLoop.Close();

                if (!_running)
                {
                    _logger.LogDebug("Game loop exited gracefully via disposal.");
                }
                else
                {
                    _logger.LogDebug("Game loop exited gracefully via game loop.");
                }
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "Error in game loop.");
            }
        }