Game Engines

I suppose game engines are the bones of the game, the frame on which to apply the muscle, the blood, the flesh! Aahahhhaa! …As far as I can comprehend, the game engine governs physics, AI interaction, interaction within the game world, rendering the graphics, the scripting, and is pretty much the basis for us artists to build upon and make it all pretty and shiny with nice character models, worlds and objects for the engine to work with.

Engines are created by developers to suit their needs for the games they desire to make. Many developers choose buy current engines already popularised by games of the genre as using a pre-made engine cuts on development costs, for example, the Unreal engine. A disadvantage is that the developer will have to work around the limitations of the engine which could be restricting on the potential of what can be achieved within the game. Having to start an engine from scratch is expensive and difficult but is often vital to create those particular and original games. Other engine technologies include additional engines for the individual purposes and needs of the game, such as separate AI or physics engines that a developer can purchase and add to their current engine.

Now, finding out about subtractive and additive game development hurt my head but as far as I can tell, they are terms simply used to describe the production of a playable space or environment within a game. In an additive environment, you start with emptiness, or “The Void”, a space in which you can create your objects and build up your level. Examples include the Quake and Half-Life engines. Alternately, the subtractive environment is the opposite and begins with “infinite solid”, which you have to carve into and extract areas to create the environment. This is how the Unreal engine works. Interesting stuff, and it makes me more eager to get my ass in gear and have a go with the Unreal Editor.

Now with next-gen engines, the key issues seem to be on engines with powerful shaders and the manipulation of light. The engine used within Crysis, CryENGINE2, is said to use subsurface scattering, where light is able to penetrate translucent surfaces (such as skin) and is reflected at irregular angles before passing back out. It makes for some scarily realistic looking stuff and I’m sure you’ll agree.

Image from Crytec's "Crysis", showing subsurface scattering