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Descent (video game)
Encyclopedia
Descent is a 3D
first-person shooter
video game developed by Parallax Software
and released by Interplay Entertainment Corp.
in 1995. The game features six degrees of freedom
gameplay and garnered several expansion pack
s. It spawned two direct sequels: Descent II
and Descent 3.
The trademark registration for Descent was allowed to lapse by Interplay in 2002 and was re-registered in 2008.
, from the Moon
to Mercury
, then outbound towards Pluto's moon Charon
. After defeating the boss robot on Charon, the Material Defender is informed he cannot return to the PTMC's headquarters in Earth orbit, as there is a chance his ship may be infected with the same virus as the defeated robots. His employer also mentions that PTMC has lost contact with their deep-space installations outside the Solar system, hinting at what is going to happen in the sequel.
Descent also features a complementary points system. Players can score points by destroying enemy robots, picking up power-ups, and detonating the reactor. Bonus points are awarded on completion of each level. These bonus points are based on the player's shield and energy count, the skill level played, and a combination of picking up any hostages and safely rescuing them.
or nausea – a common complaint found in reviews for the game.
The player is given the choice to natively use a keyboard, mouse, joystick, or combinations of these devices. Use of a second input device with or without a keyboard provides a greater amount of control due to the additional degrees of movement. The game also supports the use of two independently configured joysticks.
Like DOOM
, Descent provides a navigational wire frame
map that displays any area of the mine visited or seen by the player, which revolves around the player's position. Use of the slide controls (commonly the joystick "Hat" switch) allows the player to navigate to areas of the map away from their current location. The use of wire-frame models meant that areas at varying distances would appear to mix together when overlapping. This was overcome in Descent 3 with the use of opaque wall brushes
and lighting closely matching that found in-game. Additionally, Descent 3's map system allowed the player the ability to move the viewpoint through the tunnels in map mode.
, the next two on Venus
, and two more on Mercury
. The seventh level features the game's first boss rather than a reactor, and was the last level of the shareware. In the full version, the player moves on through twenty more mines in an outward pattern from Earth: Mars
, Io
, Europa
, Ganymede
, Titan
, Hyperion
, Tethys
, Miranda
, Oberon
, Triton
, Nereid
, Pluto
, and the final level and boss fight on Charon
.
The player accesses the three secret levels using alternative exit doors hidden in specific levels.
s floating in the mines or ejected by destroyed enemies. Energy can also be topped up (to a maximum of 100) units at "energy centers," permanent recharge locations.
Descent uses shield power as health
. Like energy, the ship "maxes out" at 200 shield units; unlike energy, shields can only be restored by acquiring "shield orb" power-ups. If the player finishes a level with shield power or energy power below 100 units, the ship will be recharged to 100 units for the next level.
When the player's ship is destroyed, all acquired power-ups and weapons are strewn about the area as power-ups.
and is touted as being one of the first games to allow initiating sessions conveniently from a menu within the game as well as on-the-fly joining of multiplayer games, whereas in many similar games of the era, such as Doom, it is presumed that all players have to be queued prior to initiating the match.
With the advent of Internet IPX
clients such as Kali
and Kahn, Descent and Descent II were increasingly played over the Internet. Descent II was especially popular online due to its support for short packets and variable packet rate, which significantly improved quality of play over the slower Internet connections prevalent at the time.
Since then, Descent source ports have added UDP support.
and is (with some tweaking) playable on 386
-based PCs
at 33 MHz. However, for good-quality rendering with full-screen view and better than minimal render depth, a 486
running at least 66 MHz is required. For maximum rendering quality, a faster Pentium
CPU is required; with the release of the Pentium, the performance requirements were no longer an issue. While Descent generally runs fine on PC's using Windows 95
, it is not compatible with Windows XP
. Descent was ported to Apple
's Power Macintosh
in 1996 and both versions support multiplayer network play over a variety of protocols. A console port of Descent was created for the Sony
PlayStation. Another console port for the Sega Saturn
was developed and was internally playable, but never released. Interplay, the publisher, as well as Parallax, the developer lost faith in the economic viability of the project. [Mike Kulas, Parallax Software]
's Doom (December 1993). Like most games of its era, Descent uses a software renderer, because mainstream 3D graphics accelerator cards did not exist at the time. However, while most of its contemporaries—Doom included—use sprites
, to render enemies, Descent renders enemies in full 3D using polygon meshes, a technique employed by Quake the following year. (However, Descent does use sprites for power-ups and the hostages.) Unlike Doom and Quake, Descent does not use BSP
trees for visibility culling (to speed up rendering), instead taking advantage of the game's use of collections of cubes to form rooms and tunnels. This system was very efficient, and made possible one of the first true 3D textured environments in a video game. On lower-end systems, detail levels could be reduced to cut out some of the smaller polygons on robots and render solid color blocks in place of textures on distant walls and across passageways in the distance.
The original Descent uses indexed 8-bit
color in DOS's display mode 13h
, using 320 × 200 resolution. Unlike its sequel, it uses only one 256-color set during gameplay, rather than a unique set for each group of levels; these colors tinge red during damage and purple during fusion charging. The Macintosh and later PC versions allow higher resolutions, such as 640 × 480. The default engine uses a software renderer in which the perspective transformation for texture mapping is only performed once every 32 pixels, causing textures to appear to pop or shift when viewed from certain angles. The software renderer also uses nearest-neighbor texture filtering, as opposed to bilinear filtering
or trilinear filtering
used by modern video cards. Nearest-neighbor texture filtering causes aliasing artifacts, such as blocky textures. These rendering compromises allowed the game to be played on most PCs contemporary with it, while better rendering techniques would have prevented it from being run on any but the most powerful gaming PCs in 1995.
The engine for Descent is a portal rendering
engine, operating on the premise of interconnected cube-shaped sectors. Sides of cubes can be attached to other cubes, or display up to two texture maps. Cubes can be deformed so long as they remain convex
. To create effects like doors and see-through grating, walls could be placed at the connected sides of two cubes. Descent introduced an elaborate static lighting scheme as well as simple dynamic lighting, where the environment could be lit with flares—another advancement compared to Doom. (Descent II later added more dynamic lighting effects, including the ability to shoot out light fixtures.)
to the original Descent (minus the audio code, which was replaced with that of the Allegro library
) was released in 1997. The source code to Descent II was subsequently released in 1999. Parallax Software released the source code to the original Descent and Descent II under the terms of a non-free
source code license in which that all commercial or revenue-generating distribution is restricted.
and Nivek Ogre of Skinny Puppy
), prerendered cinematics (using the same cinematic engine as Descent II
), and radiosity colored lighting effects.
in the winter of 2010.
, an RPG that used a modified version of the Descent graphics engine, but that was otherwise unrelated as it took place in a Medieval fantasy setting.
Perhaps the most well-known "Descent clone" was Forsaken, which was released in 1998 for PC, PlayStation, and Nintendo 64
. Forsaken had similar graphics to Descent, and almost identical gameplay.
Descent: FreeSpace – The Great War was released by Volition, Inc. in 1998. It shared the Descent name, but otherwise had no connection to the series; it was given the "Descent" prefix to avoid trademark issues (in Europe, it was released as Conflict: FreeSpace – The Great War). FreeSpace was a space simulator, and while it was still technically a 3D shooter, it did not retain Descent's characteristic "six degrees of freedom" control scheme, save for a cheat code that would force the player's ship to loosely mimic Descent's physics. Some early drafts of the FreeSpace story had the pilot searching for Descent's "Material Defender" , but the story of the finished game was unrelated.
Around that time, Volition also began work on Descent 4
, but development was canceled in 2000, owing mostly to disappointing sales of Descent 3. Descent 4 may have been originally planned as a prequel to Descent, and reportedly served as a basis for the first-person shooter Red Faction
. Similarities include a reference to a "humans first" strike in Descents opening briefing, and plot points such as nanotechnology, an evil faceless corporation, and the virus they are attempting to harness. Mike Kulas (president of Volition) stated in an interview that the Red Faction and Descent universes are strictly separate, however he did admit that code intended for Descent 4 had been used in Red Faction.
3D computer graphics
3D computer graphics are graphics that use a three-dimensional representation of geometric data that is stored in the computer for the purposes of performing calculations and rendering 2D images...
first-person shooter
First-person shooter
First-person shooter is a video game genre that centers the gameplay on gun and projectile weapon-based combat through first-person perspective; i.e., the player experiences the action through the eyes of a protagonist. Generally speaking, the first-person shooter shares common traits with other...
video game developed by Parallax Software
Parallax Software
Parallax Software was a video game developer best known for creating the Descent series of computer games. Parallax Software was started in 1993 by Matt Toschlog and Mike Kulas. After the release of Descent II in 1997, the company was split to form Volition, Inc. in Champaign, Illinois, and...
and released by Interplay Entertainment Corp.
Interplay Entertainment
Interplay Entertainment Corporation is an American video game developer and publisher, founded in 1983 as Interplay Productions by Brian Fargo. The company had been a quality developer until they started publishing their own games in 1988, like Neuromancer and Battle Chess. The company was renamed...
in 1995. The game features six degrees of freedom
Six degrees of freedom
Six degrees of freedom refers to motion of a rigid body in three-dimensional space, namely the ability to move forward/backward, up/down, left/right combined with rotation about three perpendicular axes...
gameplay and garnered several expansion pack
Expansion pack
An expansion pack, expansion set, or supplement is an addition to an existing role-playing game, tabletop game or video game. These add-ons usually add new game areas, weapons, objects, and/or an extended storyline to a complete and already released game...
s. It spawned two direct sequels: Descent II
Descent II
Descent II is a 3D first-person shooter video game noted for popularizing the use of true 3D rendering technology and providing the player with six full degrees of freedom to move and to look around....
and Descent 3.
The trademark registration for Descent was allowed to lapse by Interplay in 2002 and was re-registered in 2008.
Storyline
The game begins with a briefing between a bald anonymous executive (in later games named Dravis) of the Post Terran Minerals Corporation (PTMC) and the player, a "Material Defender" (revealed as MD1032 in the briefings, also using the callsign "Vertigo-1") hired on a mercenary basis to eliminate the threat of an alien computer virus infecting the robots used for off-world mining operations. The game progresses through the Solar systemSolar System
The Solar System consists of the Sun and the astronomical objects gravitationally bound in orbit around it, all of which formed from the collapse of a giant molecular cloud approximately 4.6 billion years ago. The vast majority of the system's mass is in the Sun...
, from the Moon
Moon
The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...
to Mercury
Mercury (planet)
Mercury is the innermost and smallest planet in the Solar System, orbiting the Sun once every 87.969 Earth days. The orbit of Mercury has the highest eccentricity of all the Solar System planets, and it has the smallest axial tilt. It completes three rotations about its axis for every two orbits...
, then outbound towards Pluto's moon Charon
Charon (moon)
Charon is the largest satellite of the dwarf planet Pluto. It was discovered in 1978 at the United States Naval Observatory Flagstaff Station. Following the 2005 discovery of two other natural satellites of Pluto , Charon may also be referred to as Pluto I...
. After defeating the boss robot on Charon, the Material Defender is informed he cannot return to the PTMC's headquarters in Earth orbit, as there is a chance his ship may be infected with the same virus as the defeated robots. His employer also mentions that PTMC has lost contact with their deep-space installations outside the Solar system, hinting at what is going to happen in the sequel.
Objectives
The game requires the player to navigate labyrinthine mines while fighting virus-infected robots. The player is given the clear objective to find and destroy each mine's reactor core and escape before the mine is destroyed by the meltdown. To obtain access to the reactor, the player must collect the blue, yellow, and red access keys for each location. As an optional objective, the player can also choose to rescue PTMC workers that were taken hostage by the infected robots.Descent also features a complementary points system. Players can score points by destroying enemy robots, picking up power-ups, and detonating the reactor. Bonus points are awarded on completion of each level. These bonus points are based on the player's shield and energy count, the skill level played, and a combination of picking up any hostages and safely rescuing them.
Movement and navigation
Descent demands that players keep their sense of orientation in a fully 3D environment with a flight model featuring six degrees of freedom in zero-gravity. Traditional FPS games require the player to only control two axes and their heading. By employing six degrees of movement, the player is given additional control for vertical movement and banking, introducing more movement controls than traditional FPS games. Descent's unique movement controls also increase the possibility for players to experience motion sicknessMotion sickness
Motion sickness or kinetosis, also known as travel sickness, is a condition in which a disagreement exists between visually perceived movement and the vestibular system's sense of movement...
or nausea – a common complaint found in reviews for the game.
The player is given the choice to natively use a keyboard, mouse, joystick, or combinations of these devices. Use of a second input device with or without a keyboard provides a greater amount of control due to the additional degrees of movement. The game also supports the use of two independently configured joysticks.
Like DOOM
Doom
Doom may refer to:* dōm, the Anglo-Saxon word meaning "judgment", "law"** Doom book the Laws of King Aelfred, Legal Code of Alfred the Great, Code of Alfred 893* Doom , a painting that depicts the Last Judgment...
, Descent provides a navigational wire frame
Wire frame model
A wire frame model is a visual presentation of a three dimensional or physical object used in 3D computer graphics. It is created by specifying each edge of the physical object where two mathematically continuous smooth surfaces meet, or by connecting an object's constituent vertices using straight...
map that displays any area of the mine visited or seen by the player, which revolves around the player's position. Use of the slide controls (commonly the joystick "Hat" switch) allows the player to navigate to areas of the map away from their current location. The use of wire-frame models meant that areas at varying distances would appear to mix together when overlapping. This was overcome in Descent 3 with the use of opaque wall brushes
Brush (video game)
Brushes are used in some 3D video games such as games based on the Source engine, its predecessor the Goldsrc engine, Unreal Engine's tool Unreal Editor, etc. to construct levels. Brushes can be primitive shapes , pre-defined shapes , or custom shapes...
and lighting closely matching that found in-game. Additionally, Descent 3's map system allowed the player the ability to move the viewpoint through the tunnels in map mode.
Levels
Descent features 30 levels, three of which are secret levels. Each level was based in a mine located in various locations in the solar system. The first three levels begin on the MoonMoon
The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...
, the next two on Venus
Venus
Venus is the second planet from the Sun, orbiting it every 224.7 Earth days. The planet is named after Venus, the Roman goddess of love and beauty. After the Moon, it is the brightest natural object in the night sky, reaching an apparent magnitude of −4.6, bright enough to cast shadows...
, and two more on Mercury
Mercury (planet)
Mercury is the innermost and smallest planet in the Solar System, orbiting the Sun once every 87.969 Earth days. The orbit of Mercury has the highest eccentricity of all the Solar System planets, and it has the smallest axial tilt. It completes three rotations about its axis for every two orbits...
. The seventh level features the game's first boss rather than a reactor, and was the last level of the shareware. In the full version, the player moves on through twenty more mines in an outward pattern from Earth: Mars
Mars
Mars is the fourth planet from the Sun in the Solar System. The planet is named after the Roman god of war, Mars. It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance...
, Io
Io (moon)
Io ) is the innermost of the four Galilean moons of the planet Jupiter and, with a diameter of , the fourth-largest moon in the Solar System. It was named after the mythological character of Io, a priestess of Hera who became one of the lovers of Zeus....
, Europa
Europa (moon)
Europa Slightly smaller than Earth's Moon, Europa is primarily made of silicate rock and probably has an iron core. It has a tenuous atmosphere composed primarily of oxygen. Its surface is composed of ice and is one of the smoothest in the Solar System. This surface is striated by cracks and...
, Ganymede
Ganymede (moon)
Ganymede is a satellite of Jupiter and the largest moon in the Solar System. It is the seventh moon and third Galilean satellite outward from Jupiter. Completing an orbit in roughly seven days, Ganymede participates in a 1:2:4 orbital resonance with the moons Europa and Io, respectively...
, Titan
Titan (moon)
Titan , or Saturn VI, is the largest moon of Saturn, the only natural satellite known to have a dense atmosphere, and the only object other than Earth for which clear evidence of stable bodies of surface liquid has been found....
, Hyperion
Hyperion (moon)
Hyperion , also known as Saturn VII, is a moon of Saturn discovered by William Cranch Bond, George Phillips Bond and William Lassell in 1848. It is distinguished by its irregular shape, its chaotic rotation, and its unexplained sponge-like appearance...
, Tethys
Tethys (moon)
Tethys or Saturn III is a mid-sized moon of Saturn about across. It was discovered by G. D. Cassini in 1684 and is named after titan Tethys of Greek mythology. Tethys is pronounced |Odysseus]] is about 400 km in diameter, while the largest graben—Ithaca Chasma is about 100 km wide and...
, Miranda
Miranda (moon)
-External links:* at * at The Nine8 Planets* at Views of the Solar System* * from the...
, Oberon
Oberon (moon)
Oberon , also designated ', is the outermost major moon of the planet Uranus. It is the second largest and second most massive of the Uranian moons, and the ninth most massive moon in the Solar System. Discovered by William Herschel in 1787, Oberon is named after the mythical king of the fairies...
, Triton
Triton (moon)
Triton is the largest moon of the planet Neptune, discovered on October 10, 1846, by English astronomer William Lassell. It is the only large moon in the Solar System with a retrograde orbit, which is an orbit in the opposite direction to its planet's rotation. At 2,700 km in diameter, it is...
, Nereid
Nereid (moon)
Nereid , also known as Neptune II, is the third-largest moon of Neptune. It has a highly eccentric orbit. Nereid was discovered by Gerard Kuiper in 1949 and was the second moon of Neptune to be discovered.- Discovery and naming :...
, Pluto
Pluto
Pluto, formal designation 134340 Pluto, is the second-most-massive known dwarf planet in the Solar System and the tenth-most-massive body observed directly orbiting the Sun...
, and the final level and boss fight on Charon
Charon (moon)
Charon is the largest satellite of the dwarf planet Pluto. It was discovered in 1978 at the United States Naval Observatory Flagstaff Station. Following the 2005 discovery of two other natural satellites of Pluto , Charon may also be referred to as Pluto I...
.
The player accesses the three secret levels using alternative exit doors hidden in specific levels.
Power-ups
The primary weapons in Descent use energy, with the exception of the Vulcan cannon, which uses traditional ammunition. The player's spacecraft has a maximum energy capacity of 200 units; energy is replenished from energy power-upPower-up
In computer and video games, power-ups are objects that instantly benefit or add extra abilities to the game character as a game mechanic. This is in contrast to an item, which may or may not have a benefit and can be used at a time chosen by the player...
s floating in the mines or ejected by destroyed enemies. Energy can also be topped up (to a maximum of 100) units at "energy centers," permanent recharge locations.
Descent uses shield power as health
Health (gaming)
Health is a game mechanic used in role-playing, computer and video games to give value to characters, enemies, NPCs, and related objects. This value can either be numerical, semi-numerical as in hit/health points, or arbitrary as in a life bar....
. Like energy, the ship "maxes out" at 200 shield units; unlike energy, shields can only be restored by acquiring "shield orb" power-ups. If the player finishes a level with shield power or energy power below 100 units, the ship will be recharged to 100 units for the next level.
When the player's ship is destroyed, all acquired power-ups and weapons are strewn about the area as power-ups.
Multiplayer
Descent offers competitive multiplayer game play for up to 8 players over a LANLocal area network
A local area network is a computer network that interconnects computers in a limited area such as a home, school, computer laboratory, or office building...
and is touted as being one of the first games to allow initiating sessions conveniently from a menu within the game as well as on-the-fly joining of multiplayer games, whereas in many similar games of the era, such as Doom, it is presumed that all players have to be queued prior to initiating the match.
With the advent of Internet IPX
IPX
Internetwork Packet Exchange is the OSI-model Network layer protocol in the IPX/SPX protocol stack.The IPX/SPXM protocol stack is supported by Novell's NetWare network operating system. Because of Netware's popularity through the late 1980s into the mid 1990s, IPX became a popular internetworking...
clients such as Kali
Kali (game browser)
Kali is an IPX network emulator for DOS and Windows, enabling legacy multiplayer games to work over a modern TCP/IP network such as the Internet. Later versions of the software also functioned as a server browser for games that natively supported TCP/IP. Versions were also created for OS2 and Mac,...
and Kahn, Descent and Descent II were increasingly played over the Internet. Descent II was especially popular online due to its support for short packets and variable packet rate, which significantly improved quality of play over the slower Internet connections prevalent at the time.
Since then, Descent source ports have added UDP support.
Development
The original Descent runs under DOSDOS
DOS, short for "Disk Operating System", is an acronym for several closely related operating systems that dominated the IBM PC compatible market between 1981 and 1995, or until about 2000 if one includes the partially DOS-based Microsoft Windows versions 95, 98, and Millennium Edition.Related...
and is (with some tweaking) playable on 386
Intel 80386
The Intel 80386, also known as the i386, or just 386, was a 32-bit microprocessor introduced by Intel in 1985. The first versions had 275,000 transistors and were used as the central processing unit of many workstations and high-end personal computers of the time...
-based PCs
IBM PC compatible
IBM PC compatible computers are those generally similar to the original IBM PC, XT, and AT. Such computers used to be referred to as PC clones, or IBM clones since they almost exactly duplicated all the significant features of the PC architecture, facilitated by various manufacturers' ability to...
at 33 MHz. However, for good-quality rendering with full-screen view and better than minimal render depth, a 486
Intel 80486
The Intel 80486 microprocessor was a higher performance follow up on the Intel 80386. Introduced in 1989, it was the first tightly pipelined x86 design as well as the first x86 chip to use more than a million transistors, due to a large on-chip cache and an integrated floating point unit...
running at least 66 MHz is required. For maximum rendering quality, a faster Pentium
Pentium compatible processor
A Pentium compatible processor is a 32-bit processor computer chip which supports the instructions in the IA-32 instruction set that were implemented by the Intel P5 Pentium processor family...
CPU is required; with the release of the Pentium, the performance requirements were no longer an issue. While Descent generally runs fine on PC's using Windows 95
Windows 95
Windows 95 is a consumer-oriented graphical user interface-based operating system. It was released on August 24, 1995 by Microsoft, and was a significant progression from the company's previous Windows products...
, it is not compatible with Windows XP
Windows XP
Windows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base...
. Descent was ported to Apple
Apple Computer
Apple Inc. is an American multinational corporation that designs and markets consumer electronics, computer software, and personal computers. The company's best-known hardware products include the Macintosh line of computers, the iPod, the iPhone and the iPad...
's Power Macintosh
Power Macintosh
Power Macintosh, later Power Mac, was a line of Apple Macintosh workstation-class personal computers based on various models of PowerPC microprocessors that were developed, marketed, and supported by Apple Inc. from March 1994 until August 2006. The first models were the Power Macintosh 6100,...
in 1996 and both versions support multiplayer network play over a variety of protocols. A console port of Descent was created for the Sony
Sony
, commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....
PlayStation. Another console port for the Sega Saturn
Sega Saturn
The is a 32-bit fifth-generation video game console that was first released by Sega on November 22, 1994 in Japan, May 11, 1995 in North America, and July 8, 1995 in Europe...
was developed and was internally playable, but never released. Interplay, the publisher, as well as Parallax, the developer lost faith in the economic viability of the project. [Mike Kulas, Parallax Software]
Rendering
The shareware version of Descent was released in December 1994 with the full version released three months later, just over a year after id SoftwareId Software
Id Software is an American video game development company with its headquarters in Richardson, Texas. The company was founded in 1991 by four members of the computer company Softdisk: programmers John Carmack and John Romero, game designer Tom Hall, and artist Adrian Carmack...
's Doom (December 1993). Like most games of its era, Descent uses a software renderer, because mainstream 3D graphics accelerator cards did not exist at the time. However, while most of its contemporaries—Doom included—use sprites
Sprite (computer graphics)
In computer graphics, a sprite is a two-dimensional image or animation that is integrated into a larger scene...
, to render enemies, Descent renders enemies in full 3D using polygon meshes, a technique employed by Quake the following year. (However, Descent does use sprites for power-ups and the hostages.) Unlike Doom and Quake, Descent does not use BSP
Binary space partitioning
In computer science, binary space partitioning is a method for recursively subdividing a space into convex sets by hyperplanes. This subdivision gives rise to a representation of the scene by means of a tree data structure known as a BSP tree.Originally, this approach was proposed in 3D computer...
trees for visibility culling (to speed up rendering), instead taking advantage of the game's use of collections of cubes to form rooms and tunnels. This system was very efficient, and made possible one of the first true 3D textured environments in a video game. On lower-end systems, detail levels could be reduced to cut out some of the smaller polygons on robots and render solid color blocks in place of textures on distant walls and across passageways in the distance.
The original Descent uses indexed 8-bit
8-bit
The first widely adopted 8-bit microprocessor was the Intel 8080, being used in many hobbyist computers of the late 1970s and early 1980s, often running the CP/M operating system. The Zilog Z80 and the Motorola 6800 were also used in similar computers...
color in DOS's display mode 13h
Mode 13h
Mode 13h is the IBM VGA BIOS mode number for a specific standard 256 color mode on IBM's VGA graphics hardware. It features a resolution of 320×200 pixels and was used extensively in computer games and art/animation software of the late 1980s and early- to mid-1990s...
, using 320 × 200 resolution. Unlike its sequel, it uses only one 256-color set during gameplay, rather than a unique set for each group of levels; these colors tinge red during damage and purple during fusion charging. The Macintosh and later PC versions allow higher resolutions, such as 640 × 480. The default engine uses a software renderer in which the perspective transformation for texture mapping is only performed once every 32 pixels, causing textures to appear to pop or shift when viewed from certain angles. The software renderer also uses nearest-neighbor texture filtering, as opposed to bilinear filtering
Bilinear filtering
Bilinear filtering is a texture filtering method used to smooth textures when displayed larger or smaller than they actually are.Most of the time, when drawing a textured shape on the screen, the texture is not displayed exactly as it is stored, without any distortion...
or trilinear filtering
Trilinear filtering
Trilinear filtering is an extension of the bilinear texture filtering method, which also performs linear interpolation between mipmaps.Bilinear filtering has several weaknesses that make it an unattractive choice in many cases: using it on a full-detail texture when scaling to a very small size...
used by modern video cards. Nearest-neighbor texture filtering causes aliasing artifacts, such as blocky textures. These rendering compromises allowed the game to be played on most PCs contemporary with it, while better rendering techniques would have prevented it from being run on any but the most powerful gaming PCs in 1995.
The engine for Descent is a portal rendering
Portal rendering
In computer-generated imagery and real-time 3D computer graphics, portal rendering is an algorithm for visibility determination. For example, consider a 3D computer game environment, which may contain many polygons, only a few of which may be visible on screen at a given time...
engine, operating on the premise of interconnected cube-shaped sectors. Sides of cubes can be attached to other cubes, or display up to two texture maps. Cubes can be deformed so long as they remain convex
Convex set
In Euclidean space, an object is convex if for every pair of points within the object, every point on the straight line segment that joins them is also within the object...
. To create effects like doors and see-through grating, walls could be placed at the connected sides of two cubes. Descent introduced an elaborate static lighting scheme as well as simple dynamic lighting, where the environment could be lit with flares—another advancement compared to Doom. (Descent II later added more dynamic lighting effects, including the ability to shoot out light fixtures.)
Third-party development
The source codeSource code
In computer science, source code is text written using the format and syntax of the programming language that it is being written in. Such a language is specially designed to facilitate the work of computer programmers, who specify the actions to be performed by a computer mostly by writing source...
to the original Descent (minus the audio code, which was replaced with that of the Allegro library
Allegro library
Allegro is a free and open source software library for video game development.The functionality of the library includes support for basic 2D graphics, image manipulation, text output, audio output, midi music, input and timers, as well as additional routines for fixed-point and floating-point...
) was released in 1997. The source code to Descent II was subsequently released in 1999. Parallax Software released the source code to the original Descent and Descent II under the terms of a non-free
Proprietary software
Proprietary software is computer software licensed under exclusive legal right of the copyright holder. The licensee is given the right to use the software under certain conditions, while restricted from other uses, such as modification, further distribution, or reverse engineering.Complementary...
source code license in which that all commercial or revenue-generating distribution is restricted.
Descent Mission Builder (1995)
A commercial Descent level editor, created by Bryan Aamot of Brainware and was published by Interplay Productions. Users can create their own single-player and multi-player levels with the program and then play them.Descent: Levels of the World (1995)
A popular add-on for Descent, containing all of the entries from a level design competition held by Interplay in 1995. A viewer is included, allowing the player to see a preview of each map, as well as selecting ones that received a "Top 10" award or an honorable mention.Descent: Anniversary Edition (1996)
A bundle released on the one-year anniversary of the original game's debut, the Anniversary Edition featured Descent, the Levels Of The World add-on, and several additional levels created by Parallax.Descent 1 and 2 "The Definitive Collection" (1997)
This included Descent, the Levels Of The World add-on, and several additional levels created by Parallax. It also included Descent II, the Descent II: Vertigo, and the Descent Mission Builder 2. There was also a preview of the upcoming Descent 3.Descent on PlayStation (1996)
A version of Descent was also produced for the PlayStation. It features thirty levels, with five new anarchy levels, the remixed soundtrack from the MacOS version (featuring Type O NegativeType O Negative
Type O Negative was a gothic metal band from Brooklyn, New York City. The band also incorporated elements of doom metal and thrash metal. Their dramatic lyrical emphasis on themes of romance, depression, and death resulted in the nickname "The Drab Four"...
and Nivek Ogre of Skinny Puppy
Skinny Puppy
Skinny Puppy is a Canadian industrial musical group, formed in Vancouver, British Columbia, Canada in 1982. The group is widely considered to be the founders of the electro-industrial genre....
), prerendered cinematics (using the same cinematic engine as Descent II
Descent II
Descent II is a 3D first-person shooter video game noted for popularizing the use of true 3D rendering technology and providing the player with six full degrees of freedom to move and to look around....
), and radiosity colored lighting effects.
Descent on WiiWare
Interplay announced that there will be a version of Descent for the WiiWareWiiWare
WiiWare is a service that allows Wii users to download games and applications specifically designed and developed for the Wii video game console made by Nintendo. These games and applications can only be purchased and downloaded from the Wii Shop Channel under the WiiWare section...
in the winter of 2010.
Related titles
In 1997, Interplay released Descent to UndermountainDescent to Undermountain
Descent to Undermountain is a computer role-playing game created and distributed by Interplay in 1997. It was developed by Chris Avellone, Scott Bennie, John Deiley, Robert Holloway, and Steve Perrin. The game is based on the Dungeons & Dragons fantasy role-playing game, which was published at the...
, an RPG that used a modified version of the Descent graphics engine, but that was otherwise unrelated as it took place in a Medieval fantasy setting.
Perhaps the most well-known "Descent clone" was Forsaken, which was released in 1998 for PC, PlayStation, and Nintendo 64
Nintendo 64
The , often referred to as N64, was Nintendo′s third home video game console for the international market. Named for its 64-bit CPU, it was released in June 1996 in Japan, September 1996 in North America, March 1997 in Europe and Australia, September 1997 in France and December 1997 in Brazil...
. Forsaken had similar graphics to Descent, and almost identical gameplay.
Descent: FreeSpace – The Great War was released by Volition, Inc. in 1998. It shared the Descent name, but otherwise had no connection to the series; it was given the "Descent" prefix to avoid trademark issues (in Europe, it was released as Conflict: FreeSpace – The Great War). FreeSpace was a space simulator, and while it was still technically a 3D shooter, it did not retain Descent's characteristic "six degrees of freedom" control scheme, save for a cheat code that would force the player's ship to loosely mimic Descent's physics. Some early drafts of the FreeSpace story had the pilot searching for Descent's "Material Defender" , but the story of the finished game was unrelated.
Around that time, Volition also began work on Descent 4
Descent 4
Descent 4 is a planned fourth installment in the Descent series published by the re-emerging publisher, Interplay Entertainment. While the game has had a troubled development history, Interplay Entertainment confirmed in 2008 that they have plans for developing the game after raising funds for the...
, but development was canceled in 2000, owing mostly to disappointing sales of Descent 3. Descent 4 may have been originally planned as a prequel to Descent, and reportedly served as a basis for the first-person shooter Red Faction
Red Faction
Red Faction is a first-person shooter video game developed by Volition, Inc. and published by THQ. It was released for the PlayStation 2, Microsoft Windows and Mac in 2001. A version for the Nokia N-Gage was developed by Monkeystone Games. The game was also re-developed as a top-down shooter for...
. Similarities include a reference to a "humans first" strike in Descents opening briefing, and plot points such as nanotechnology, an evil faceless corporation, and the virus they are attempting to harness. Mike Kulas (president of Volition) stated in an interview that the Red Faction and Descent universes are strictly separate, however he did admit that code intended for Descent 4 had been used in Red Faction.
External links
- Official Descent page at InterplayInterplay EntertainmentInterplay Entertainment Corporation is an American video game developer and publisher, founded in 1983 as Interplay Productions by Brian Fargo. The company had been a quality developer until they started publishing their own games in 1988, like Neuromancer and Battle Chess. The company was renamed...
- Descent source code