Game Loop and Typical Implementation

Synonyms

Game engine loop; Game engine main loop; Game engine update loop

Definitions

At the innermost core of every game engine is a compact infinite loop. This loop continuously iterates through the steps of receiving and processing player input, updating the entire game state, and rendering and displaying the game objects. This loop is executed at a short but discretised time interval supporting seemingly instantaneous interactions between the players’ input and the graphical gaming elements. This constantly running loop is referred to as the game loop.

Introduction

To convey a lifelike sense of instantaneity, each cycle of the game loop must be completed within a normal human’s reaction time. This is often referred to as real time: the amount of time that is too short for humans to perceive both visually and cognitively. Typically, real-time can be achieved when the game loop is running at a rate of at least 40–60 cycles in a second. The speed of a standard game loop, with one...