Keep game in sync

There can be hard to keep the game in exact sync. I found this article with Glenn Fiedler that describe how you keep everything in sync even when graphic very in speed.

Everything is written for C++ but I use LibGDX where some step are built in, so I had to convert it. I did skip the last part he talk about because my game just don’t benefit from it. The code went very clean in the end.

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float timeToProgress = 0.01f;
public void update(float delta) {
  if (delta > 0.25)
    delta = 0.25f;
  accumulator += delta;
  while (accumulator >= timeToProgress) {
    worldController.update(timeToProgress);
    accumulator -= timeToProgress;
  }
  worldRender.render();
}

First if-statement just make sure I don’t run into a spiral of death, if calculation on the word take more then 25 milliseconds it just set 25. Then I add delta and loop so many times I need, so if there been 5 milliseconds from last time update was called it will loop 5 times and do the update to the world. Last thing is just render everything out.