Game Loop Architecture

Understanding the Game Loop Foundation

The game loop is the heartbeat of any interactive system. It manages the continuous cycle of input processing, logic updates, and rendering that creates the illusion of real-time interaction.

Core Components

Every game loop consists of three primary phases:

1. Input Processing - Collecting and interpreting player actions
2. Update Logic - Modifying game state based on the accumulated input
3. Rendering - Displaying the current state to the player

Fixed Timestep Considerations

A critical decision in game loop design is whether to use a fixed or variable timestep. Fixed timesteps provide consistency and predictability, while variable timesteps can optimize performance in low-resource environments.

deltaTime = clock.tick()
accumulator += deltaTime

while accumulator >= FIXED_TIMESTEP:
    update(FIXED_TIMESTEP)
    accumulator -= FIXED_TIMESTEP

render(accumulator / FIXED_TIMESTEP)

Performance Implications

The game loop frequency directly impacts perceived smoothness and responsiveness. A 60 Hz loop provides approximately 16.67 milliseconds per frame, creating a tight constraint on processing time.

Event Synchronization

In narrative games, the game loop must synchronize with story events. This requires a messaging system that allows systems to communicate without tight coupling.

The game loop architecture becomes the foundation for all subsequent systems, making early decisions crucial for long-term maintainability.