It's probably for the sake of an example, but writing a game/render loop with Sleep is a bad idea, perhaps even on a realtime OS. What you should be doing is to

It's probably for the sake of an example, but writing a game/render loop with Sleep is a bad idea, perhaps even on a realtime OS. What you should be doing is to render the frame that's meant for the current time. This way slowdowns, hiccups, boosts don't alter the speed of animations, and you can regulate how frequent you render regardless of the timer precision.