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.");
}
}