Game Loop
Runs the frame-by-frame cycle that reads input, updates logic, updates physics, updates audio, and renders the screen.
Engine Breakdown
Game engine systems
A game engine is made of specialized systems that work together to create a smooth interactive world.
Renderer
Draws sprites, models, lighting, shadows, materials, particles, post-processing, and the final image.
Camera
Controls what the player sees, including perspective, field of view, following behavior, shake, zoom, and cutscenes.
Asset Pipeline
Imports, converts, compresses, organizes, and loads models, images, sounds, animations, scripts, and level data.
Scene System
Organizes levels and worlds into objects with positions, rotations, components, scripts, lights, and cameras.
Components
Lets developers attach reusable behaviors such as renderers, colliders, rigidbodies, audio sources, and custom scripts.
Physics
Handles gravity, velocity, collisions, triggers, rigidbodies, raycasts, friction, and movement simulation.
Input
Reads keyboard, mouse, controller, touchscreen, and other device input, then maps that input to game actions.
Scripting
Defines gameplay rules, object behavior, player actions, enemy reactions, scoring, progression, and events.
Animation
Controls movement, state machines, blending, cutscenes, character poses, inverse kinematics, and animation events.
Audio
Plays sound effects, music, ambience, voice lines, UI sounds, spatial audio, reverb, and audio zones.
AI
Controls enemies and NPCs using state machines, behavior trees, pathfinding, perception, utility decisions, and scripts.
User Interface
Creates menus, HUDs, health bars, inventory screens, dialogue boxes, maps, buttons, subtitles, and settings screens.
Networking
Keeps multiplayer games synchronized using servers, clients, replication, prediction, lag compensation, and authority rules.
Save System
Stores progress such as inventory, player position, quests, world changes, settings, achievements, and unlocked content.
Build System
Packages the game into a playable build for Windows, macOS, Linux, web, console, mobile, or VR platforms.
Engine vs. game
The engine is the reusable technology. The game is the specific content, rules, art, sound, levels, story, and experience built with that technology.
Engine = kitchen Game = meal Assets = ingredients Code = recipe Developers = chefs Players = hungry goblins with controllers
The same engine can power a 2D platformer, a 3D horror game, a VR simulator, a racing game, or a multiplayer shooter. The engine provides the tools. Developers create the experience.