Id Software are something of an anomaly in the games industry. Not only can they promise the world, but inevitably they deliver it too, and in an era when anti-hype has crushed some previously highly anticipated releases, it is something of a testament to the skill of the Texas based developers that nobody in the industry doubts that Doom 3 will be a major success. With the game's release arriving at the end of 2003 or early 2004 (the old 'when it's done' scenario), perhaps it's time to recap on the story so far, as it were.
Id have always gone their own way. Despite their massive critical and financial successes over the years, they have resisted the temptation to grow for growths sake - Id still numbers around the 20 employees mark. This is partly down to Carmack's well known apathy towards anything other than programming and rocketry, but also perhaps partly due to the fact that Id is one of the few developers out there lacking in outright leadership. Carmack himself owns 40% of the company, with artists Adrian Carmack and Kevin Cloud holding over 50% and the remainder spread between other employees. The result is a level of infighting that would tear other companies apart. Indeed, divisions were rife over the decision to make Doom 3 itself, and eventually resulted in the sacking of artist Paul Steed after he organised a rebellion of employees who were in favour remaking the early classic.
Once development began, however, further strife was avoided and the game is now considered technologically complete, with only minor fixes and changes ahead before final release sometime in the next eight months. That, of course, does not mean that there is not considerable work to be done. The much vaunted Doom 3 technology causes the developers some considerable problems as well as offering opportunities. The root of the problem is the massively increased level of detail the engine can handle - this looks incredible but it must first be generated, and the increased content needs of a graphics engine that can handle models of up to 250,000 polygons take a considerable toll on a small company like Id.
Carmack's genius was to design an engine that utilised models built to full CG specifications, and then convert them to a low polygon version with very little noticeable loss of detail. This is accomplished through a variety of means, the most important of which is modelling the shadows created on the full CG model in a texture format, creating the illusion of a far higher polygon count.
The engine is, of course, the real star of the show. Carmack has always shown incredible foresight, and Doom 3 will be the first mainstream game engine to offer dynamic lighting. In older engines (Quake 3 and before, Unreal, etc.), when a level designer compiles a level, the compiler calculates the lighting of the level based on the position and strength of the light sources placed within it, including a certain amount of reflected light (light that bounces-off surfaces). This information is stored in something called a lightmap that is used, along with the level geometry, to load the level that the player sees. Doom 3, however, does away with such lightmaps once and for all by calculating the effects of all light sources dynamically during the game.
This has several important implications. In the older engines lightmaps imposed limits on the amount of lighting that could be changed in the game - perhaps the main character might have a shadow, as well as the enemies. Later iterations might introduce new tricks to make the light seem more dynamic - light switches, shooting out lights, etc. But the fact is, in Doom 3, all lighting is dynamic. Shoot a ceiling lamp and it will swing, and all the objects in the room will have their shadows recalculated on the fly. One consequence of the move to dynamic lighting is the loss of reflected light calculations, meaning that any area where there is no direct lighting will be rendered black, but this is a small matter for a game designed to invoke fear. These changes bring tremendous possibilities, however, and for the first time we should see lighting techniques inherited from cinema being utilised to create fear, suspense and foreboding.