Polygon based engines, however, remained the most popular and effective way of delivering 3D gameplay, and as computing power increased throughout the late 1980’s designers improved the technology. A PC port of the BBC micro and Acorn computer title Elite, Elite Plus was a complex trading and combat simulation, wherein the player was given a spaceship and a small amount of funds then tasked with traveling to various star systems and earning money. Firebird Software’s 1987 release of Elite Plus represents one of the first documented implementations of filled polygons (Rollings, 516-517), a technique that solved the “glass enemies” issues of Battlezone by calculating and removing lines that would be blocked in a solid object. By combining these calculations with the ability to fill the polygons that made up the enemy ships with color, Elite Plus created enemies that had the illusion of a solid construction. This was a crucial step towards realism. Elite Plus also featured an impressive amount of gameplay for its time, with eight galaxies and thousands of planets. Even today, having a designer specifically craft such a universe would be a daunting task, so the authors of the software chose to use a technique of pseudo-random generation of the worlds, allowing a complex universe in a relatively small amount of space with a minimum of design effort.
The id Software title Wolfenstein 3D, released in 1992, is generally accepted as the start of the “First-Person Shooter” genre of 3D games, but id software was not the first to experiment with texture mapped 3D games. That honor goes to the now-defunct Looking Glass Technologies for their March 1992 title Ultima Underworld: The Stygian Abyss, which was also the first Role Playing Game, or RPG, to feature first-person action in a 3D environment. All 3D RPG titles from Morrowwind to World of Warcraft share Ultima Underworld as a common ancestor, both graphically and spiritually, though World of Warcraft utilizes a slightly different third person perspective. For better or for worse, Underworld moved the text-based RPG out of the realm of imagination and into the third dimension.
Ultima Underworld: The Stygian Abyss featured an extremely advanced graphical engine, far more advanced than what the better known Wolfenstein 3D would support. Underworld could support a number of features that would not appear again until the release of Doom on December 10th, 1993 and, in at least one case, the release of Duke Nukem 3D years later on January 29th, 1996. While Wolfenstein would consist of a world with only 90 degree angles and ceilings all of the same height, Underworld allowed the use of varying height ceilings, and walls at 45 degree angles, allowing for much more complex and realistic architecture. Further, while id software’s Doom and Apogee’s Rise of the Triad would introduce stairs, it would not be until Duke Nukem 3D that a major title from a company other than Looking Glass would feature inclined surfaces, allowing ramps and other effects. All of these elements were in place in 1992 for Ultima Underworld and David Kusner states in “Masters of Doom” that id software only contemplated the idea of applying texture mapping after designer John Romero was informed of what Looking Glass was doing with Ultima Underworld. Id software’s lead programmer, John Carmack, admits that id’s game Catacombs 3D, a dungeon-based title that beat Ultima Underworld to market by 6 months, was motivated primarily by Romero’s interest in having id attempt a game with texture mapping. (Kusner, 89; Kent, 458).
The texture mapping that Carmack added to Catacombs 3D was a significant innovation over previous titles. The texture maps were simple, consisting mostly of stone walls with moss or vines across them, but combined with the black ceiling texture it helped to enhance the feeling of being outside (in certain levels) or trapped deep beneath the earth. In an e-mail to the author, former id game designer and creative director on Catacombs 3D,Tom Hall, stated that the texture mapping in Catacombs was “… the Wolfenstein technology, but in EGA”. Catacombs 3D also introduced a now-familiar element of many first-person shooter games; a visible weapon in the bottom center of the screen. In Catacombs 3D, that visible weapon was one’s hand, from which a variety of magical spells could be projected to slay enemies. Again, level design and layout were relatively simple, but the addition of the texture maps went a long way to deepening the immersion of the game.
Catacombs 3D itself was an evolution of an earlier id title called Hovertank 3D, wherein the player drove around in a hovering tank, destroying enemies with its main gun and rescuing trapped people. The gameplay was relatively straightforward, but it was the engine that was something new. Id software’s head programmer, John Carmack, was bothered by what he saw as excessively slow gameplay in flight simulator titles like Wing Commander and sought to create a faster 3D engine (Kushner 81-82). Carmack utilized a technique known as ray casting, allowing the computer to essentially draw only what the viewer could see. This meant that the first id game based on this technology, Hovertank 3D, and its successor, Catacombs 3D, were much faster than any other 3D rendered game of the time. This emphasis on speed, however, meant less complexity in the levels, at least as compared to Ultima. Since both Hovertank 3D and Catacombs 3D made it to market before Ultima, though, players were unaware of the difference. The third id game featuring the technology, Wolfenstein 3D, would prove to be a genre-defining smash title.
Wolfenstein 3D was the first commercially successful 3D
title, but was limited to movement only on two axes
Wolfenstein 3D was a remake of Castle Wolfenstein, a title programmed by the late Silas Warner and originally created for the Apple II computer in 1981 (Kent, 458). Castle Wolfenstein was subsequently ported to the Commodore 64 in 1983 and finally to DOS in 1984. The Wolfenstein 3D game engine was based on the same principles as that of Hovertank and Catacombs but with some major additions made by John Carmack. Catacombs 3D’s engine supported EGA graphics, meaning that it could only display 16 colors, far from the millions of colors the human eye can discern in real life. Wolf3D also supported 16 color graphics, but included support for the VGA standard, allowing for 256 colors, a major step up (Kushner, 97). VGA also allowed for Wolfenstein to feature higher resolutions. These graphical upgrades, combined with the speed of John Carmack’s improved rendering engine, achieved a level of immersion that surpassed anything id had done before.
The emphasis on speed, however, again led to limitations on how detailed the world was. Like Hovertank and Catacombs, the Wolf3D engine would draw just the walls, leaving the floors and ceiling a flat color (Kushner, 95; Hall). In a game set completely indoors in a Nazi castle this was a decision that ultimately had little impact on immersion, but it served to limit the flexibility of the engine. Texture mapped floors and ceilings would have to wait until id’s next project.
Interactivity in Wolf3D was relatively limited, with the player having only two ways to interact with the world; shooting things to kill them and opening doors by pressing the spacebar, a universal “use” key. Wolf3D upped the ante, though, by adding in “push walls”. These walls appeared like any of the normal solid walls in the game, but if a user hit the spacebar in front of them, the wall would slowly slide back, revealing a hidden room (Kushner, 108). Hidden rooms and secret levels would play a major part in future id games, and First-Person Shooters in general. The push walls were another innovation by Tom Hall, who served as the director of Wolfenstein 3D (Kushner, 108-112), and served to reward the player for thoroughly exploring the game world. It was an interesting gameplay mechanic, and one that grew out of a tradition in the video game industry for including secrets, or “Easter eggs” for players to find (Kent 188-189). While many would consider these “Easter eggs” to be afterthoughts, they present an important opportunity for level designers to maximize player investment and interest in the game world. Additionally, the careful placement of such Easter eggs or bonus areas can confer additional replay value to a title, as well as providing significant benefit to the curious player. Armor, medical kits and additional weaponry or ammunition are traditionally found concealed in such hidden rooms, though later FPS titles such as Duke Nukem 3D added in secret rooms that contained little benefit to the player but gave insight into the minds and interests of the game and level designers.
Wolfenstein 3D also expanded on the weapon choices available to the player. In keeping with the style established by Catacombs 3D, the player’s chosen weapon was visible at the center of the bottom of the screen. This helped both with aiming and adding a sense of actually seeing the world from your avatar’s perspective. This technique has become a standard immersive device in First Person Shooters, and later titles have expanded on the functionality, with some titles actually adding the ability so see the players own feet when they look down. DreamWorks Interactive’s 1998 First Person Shooter Trespasser, based on the Jurassic Park license, took the concept to the extreme, with the player being able to look down and see the female avatar’s ample bosom. The player avatar had a heart tattoo on the upper part of the left breast which served as a health indicator, removing the need for a health indicator in the player view.
The design of the levels in Wolf3D was accomplished using a proprietary program, called TED5, developed by John Romero (Romero; Hall). TED5 was an evolution of earlier tile-based editing programs that id used on Hovertank 3D and Catacombs 3D (Hall). The levels were designed from a top-down perspective which was simple to do since all ceilings and walls had the same height in the Wolf3D engine (Romero). Designing what Romero referred to as a “high quality level” in TED5 for Wolf3D could take “a few hours”. Romero also observes that “Back then, it didn't take much to do a Wolf3D level since it was all abstractly represented by tiles - what you saw on the screen in the editor is not what you saw on the screen in the game.” In terms of pre-production, the designers would start by laying out the episodes, general themes and enemies first, then start designing levels that the level designer themselves found to be fun. There were few if any paper sketches of levels made, since the simplicity and speed of the editor made it more time-efficient to simply create levels on the fly, versus doing extensive pre-planning. Again, such simplicity was a direct result of the limited state of the 3D presented in these early id software titles. In effect, the games were not truly three dimensional, but could better be referred to as pseudo-three dimensional, since the player did not have full range of movement, and all rooms were of a fixed height. There were no stairs in Wolf3D, no ramps, and no way to change the players’ altitude.
Many of these engine limitations would soon be overcome, however, when id software released Doom in December of 1993. Doom fundamentally altered the First-Person Shooter genre, cementing many of the innovations in Hovertank 3D and Wolfenstein 3D as fundamental elements for any FPS. Fast paced gameplay, a variety of powerful weaponry and detailed, realistic environments became hallmarks of FPS’s subsequent to the release of Doom (Kent, 459). Indeed, Doom was such a watershed moment that most of the First-Person Shooters that followed its release were referred to, somewhat derisively, as Doom clones.