Skip to content

Games

Minecraft

  • Genre: Sandbox/Expolration
  • Mechanics
  • Getting Stuff: Requires Inventory, Collision Detection, Pick up button, Items System, Destroying blocks, Gravity,
  • Movement:
  • Survival: Eating, Hunger, Enemy AI, Crafting
  • Animation
  • Combat System
  • Respawn System
  • Day/Night Cycle
  • Render the World
  • World Generation System
  • Save/Load System

The Witcher

  • Genre: RPG
  • Mechanics:
  • Complete Quests: Dialog System, Quest System, Experience System, Combat System
  • Day/Night Cycle
  • Inventory System
  • Potion Crafting System
  • Mount System
  • Physics/Collision System
  • Render Pipeline
  • Save/Load System
  • Audio System
  • Cut-Scene Manager
  • Character Selector
  • Story/Narrative System
  • Map System

Skyrim

  • Genre: RPG
  • Mechnaics:
  • Pick-Pocketing
  • Fast-Travel
  • Character Customisation
  • Economy
  • Loot-System
  • Progression and Leveling System (Trade Assignment)
  • Menus/UI
  • Save/Load System
  • Character Interaction (Relationships, )
  • Content Generation System (for e.g. quest generation)
  • Health System
  • Graphics System
  • Audio System
  • Camera System

Common Systems between Games

A game engine should have common systems:

  • Graphics
  • Input/Output
  • Movement
  • Low-Level IO (disk write, memory, etc)
  • High-Level (Keyboard, Mouse, Controllers, ...)
  • Physics
  • Collision
  • Gravity
  • Objects
  • Networking
  • Persistence
  • Music/Sound/Art
  • Memory Management

A game engine should be a fully featured, reusable software development kit. In addition efficiency is important! A game engine also should be able to accomplish the creative vision.

Pong

  1. User Input
  2. I/O System (Load System)
  3. Paddle and Ball
  4. Rendering System
  5. Collision Detection
  6. Physics
  7. Audio
  8. UI

  9. Scoring System

  10. Reset the state of the game

2D Platformer

  • IO System
  • Collision
  • Physics
  • Gravity
  • Platform-System
  • Input
  • Player
  • Winning/Loosing Condition
  • Level-System
  • UI
  • Render System
  • Animation
  • AI (on the side)
graph 
level[Level System] --> io[IO System]
level --> player
level --> platforms
level --> enemies
collision
physics --> collision
gravity --> physics
platforms --> physics

rendering --> level
ui --> rendering
ui --> win[Win Condition]

level_generation[Level Generation] --> level

Engine vs Game

An engine is...

  • ... usually more data driven
  • ... generalised
  • ... extensible
  • ... reusable

A game usually does not support this properties (, however, there are exceptions).

There are properties that both the engine and games should have, like efficiency.

Optimisations

A game engine can optimises for different things:

  • Hardware A game might be optimised for a console or a PC. Since a console has a very specific set of hardware, optimising for this is easier.

  • Style of Games

  • Graphics 2D or 3D

  • Multiplayer

P2P or server/client

However, one thing to consider, with every optimisation the game engine strays further from generalisbility.

Deadlines

A game has internal deadlines (e.g. framerate targets, asset loading, ...). Games can, and often do run without meeting these constraint. Thus, this is a soft constraint.