Guess who's back...

Engines 

Ladies and gentlemen, I've got to say it is good to be back. With thoughts to spill on a page and a course worth talking about, let's jump right in. 

Game engines are the topic of discussion so this blog is going to give a you an overview of some of the breakthrough engines created in the past decade. The ones that have set the bar and those that have created an entire community of modders - individuals who like to take the idea of making a game your own to a whole nother level. So let's begin by asking the most fundamental question, what is a game engine? 

Built not bought

A game engine is a framework of visual development tools as well as reusable software components which are provided in an integrated development environment to enable simplified and rapid development of video games in a data-driven manner. Each game engine is unique and as such no one game engine may be used to design all game  genres. There is context and precision in each engine and no two are ever alike. Back in the day, companies built their engines purely to run their games and nobody else's. Eventually, gaming companies realized that there were gamers who wanted to play around with the engines they built and along came Quake II and the Unreal Engine which provided tools for gamers to let their imaginations run wild and modify what they had built.

As engines grew in complexity and structure they were put on the market and SDKs (Software Development Kits) became available for purchase and commercial use. You may be thinking, "But you just said no game engine can be used to design all game genres." While that might be true, there is still much similarity between the mechanics and game logic of many genres and with a solid engine and a lot of tweaking, a little could go a long way. Building a game used to mean starting from scratch and re-inventing the wheel - compiling all new code. So when did this change? What changed? Who helped? 

Let's find out. 

Information found on this blog has been taken from Paul Lilly's (write for MaximumPC) article on a visual history of 3D game engines found here.

I wouldn't leave if I were you, DOS is much worse

One of the many infamous quit messages from the game that sends you on a serious guilt trip when attempting to leave. Doom was most certainly one of the most memorable and important PC games of all time. The reason for this was that Doom pushed reusable game engines as a viable programming model. The best part was that id software's Doom engine wasn't really a 3D engine at all but a very well conceived 2D sector-based engine with flat sprites representing objects, characters and anything not tied down to the map. This meant a good rendering speed for the hardware of the time which only really had to be capable of handling texture-mapped environments. 

After a time, NovaLogic came out with their Voxel Space engine, introducing the concept of a voxel (a combination of the words volumetric and pixel) which was used by several games for specific rendering of in-game items or even vehicles. Voxel was a way to represent volumetric objects as 3D bitmaps instead of as vectors. Terrain was rendered in layers making graphics more smoothly contoured and detailed. This, in turn, also provided smoother gameplay.

Build followed in the footsteps of the Doom engine with Duke Nukem 3D as far as rendering worlds on a 2D plane with sprites populating on the map went. The Build engine broke the entire world into individual sectors arranged in a grid with the ceiling and floors in each sector built at a different height. This meant that, unlike in Doom, players could now look up and down. 

Enter 3D

Let's move into the world of 3D gradually and begin with the Jedi engine. The Jedi engine was responsible for Star Wars and proved highly successful in creating 3D-like environments by allowing for areas (sectors) to be stacked. Yet, not everything was 3D with models being rendered into bitmaps form different angles in 45-degree intervals. Upto 32 angles were supported for each object which would be continually rescaled as the player got closer. 

The first truly 3D game engine was the Quake engine which had to be meticulously crafted in order to ensure that it ran smoothly without a ton of processing power. One of the neat techniques used in Quake was map purging, where an area of a map wasn't processed if the player couldn't see it. This reduced the number of polygons by at least half if not much more. Additionally, the Quake engine made use of Z-buffering, included 3D light sources and supported 3D hardware acceleration. 

Renderware is one of the more popular game engines which claims over 200 game titles on several platforms making it a multiplatform game engine. Renderware allowed developers to manipulate art and game processes in real time. That means a developer could change the paint job on a car without altering the underlying code and having to render the scene all over again. Rudimentary physics within the engine worked the same way. 

The original Quake offered hardware graphics acceleration. Along came Quake II and offered native OpenGL support and included coloured lighting effects and a new game model which allowed for both software and OpenGL renders instead of having to choose between the two. As mentioned earlier, Quake II was known for its moddability when id released their source code into the modding community in 2001 while still keeping the rest of their engine proprietary. With such a robust game engine, savvy developers were able to use it to power full-fledged role-playing games with additional features.

The Unreal engine was the main competitor to Quake II and also happened to become a popular engine in the modding community. UnrealScript was the engine's very own scripting language which was bundled with the game along with a map editor and UnrealEd (a modification program). Software and hardware rendering were both present in the Unreal engine amongst collision detection, colored lighting and rudimentary texture filtering. 

In Conclusion

With the gaming technology on the rise, there is room for a lot of growth in the game engine territory. There is so much we have yet to see and so much we have to build on. Continuing innovation gives us hope for games to grow closer and closer to reality. We look back at all the engines that have preceded our time and we admire the ingenuity of developers back then. But we also use their design patterns, their ideas and their motivation to build better and more efficient engines that will power the games of tomorrow.

It's good to be back.