Some key terms that are used in this document are defined below.
Adhesion: The ability of an object to stick to other objects
Ambient light: The overall lighting level in the environment
Avatar: The representation of a player within the game world
Azimuth: The horizontal angle of rotation for a vector from the X axis
Cohesion: The ability of an object to stick to similar objects
Co-latitude: The vertical angle of rotation for a vector from the Y axis
Deathmatch: A game where multiple players fight each other and the last one standing is the winner
Diffuse light: The amount of light that is scattered when it hits the object
Emergent behavior: A player interaction that was not explicitly defined by the creators of the game but adds to the gameplay
Heightmap: A 2D grayscale image where height is defined by color (black is the lowest value and white is the highest)
Particle system: A system that manages groups of small "particles" that represent real-world entities such as water and wind
Point light source: A light source that is placed at a single point and uniformly spreads the light at a certain radius
Shader: A program that is executed exclusively on the graphics card (GPU) which allows it to run at a high speed
Specular light: The amount of light that is directly reflected off of an object