UnrealEd
Encyclopedia
UnrealEd is the level editor
used to create levels
for Unreal
. It was also used for other games based on the Unreal engine
, such as Deus Ex
and Lineage II
, although it has changed along with the engine for later games. One of the first companies to do this with first person shooters, all Unreal games on the PC
had the level editor
included for free, and some third party Unreal engine games did the same with an edited and specialized version. This extended the longevity of the games. Amateur level designers could now create their own levels for the game, providing a near endless amount of additional content for the game. In addition, the built-in scripting language
called UnrealScript
allowed for editors to customize game content.
UnrealEd has a customizable user interface
, but the most common is the quad viewports with the top view in the top left, then, moving clockwise, the front view, the side view, and the perspective view. It has a row of buttons along the top pertaining to various options such as save, open, and rebuild, and a series of buttons to the left of the viewports which access editing functions.
shipped with UnrealEd 1.0, which displayed most of the editing tools on a single large left bar adjacent to the four viewports. This version was extremely buggy
, particularly while rebuilding maps.
Unreal Tournament
also shipped with UnrealEd 1.0, and UnrealEd 2.0 being added in a later game patch. The editor underwent a major visual change from the previously colorful buttons to a more subdued green scheme. New tools and features were added (such as search capabilities and a new 2D Shape Editor), and it also underwent a significant stability
upgrade
, and though the editor still had its share of strange crash
es, it wasn't nearly as particular as UEd 1.0. There are also some bugs
like the movers' collision (they block the bullets and they use to be like invisible walls) and the white screens (that you aren't able to see the 3D and the 2D screens)
Bundled with Unreal Tournament 2003
was UnrealEd 3, with further increased stability. It maintained the green colors, and looks virtually identical to UEd 2.0. The editor added a static mesh
browser to support static meshes (known as "hardware brushes" during development), and combined the various browsers into a single browser with tabs to switch between textures
, meshes
, actors, etc.
Future versions of UnrealEd will be fully backwards compatible with content developed under previous versions.
. Additive brushes can be solids, semisolids or nonsolids. Generally, brush geometry was used before Unreal Engine supported the use of static mesh
es. Ever since static meshes could be placed in a level, brush geometry tends to be less used and is generally discouraged.
Older versions of UnrealEd treated the world as a giant mass, from which the level designer subtracted space, in order to make the level walkable and, therefore, playable. Since UT3, UnrealEd can start with either a full, subtractive space (from which the designer subtracts geometry) or an empty, additive space (to which the designer adds geometry).
Some brushes may be movable or special brushes: such a denotation gives game designers, level designers, and level editors the ability to create moving objects within a game. These special types of brushes may be used to create waterfalls, elevators, flying carpets, doors, drawbridges, and many other types of dynamic objects. Zones can be denoted within the various brushes—after the brush has "sculpted" an area of space within the virtual 3D
environment (or level) -- effectively creating wet zones, sky zones, dry zones, or fog zones. In this way, lakes or pools can be created, interiors of buildings or exterior terrain and landscapes. Day or night may be created, through the use of "skyboxes" and other tools in the editor. Weather may be assigned to various levels or zones, allowing such features as snow, rain, or clear weather.
The basic process of CSG operations
within UnrealEd is markedly different from other computer game editors that treat the world as a giant space, such as Quake and Quake II
game level editors. In those and similar game editors, brushes are initially added to the vacant space within the game's 3D
environment in order to create virtual terrain and architecture within the level currently being edited. Both subtractive-based computer game editors (such as UnrealEd) or additive-based computer game editors (such as Qoole) may each produce stunning 3D computer graphics
for the gameplayer. Yet, each type of editor functions in nearly diametrically-opposed manners. Each type of level editor has its own advantages and disadvantages. The subtractive-based computer game editor was developed after the additive-based computer game editor.
In UnrealEd, brushes are used to compile a level into a BSP Tree
for rendering and collision detection. Unfortunately, as levels become more complicated they are prone to BSP errors, resulting in visual and collision anomalies. There are several types of BSP errors: BSP holes and hall of mirrors are two common forms. BSP errors can be very difficult to correct. This is partially why the use of Static Meshes was introduced in the Unreal 2 Engine.
Static Meshes are pre-created Polygon mesh
geometry, created in software such as Maya
or 3D Studio Max
, that can be imported and positioned within levels. Although a level's foundation and basic layout is still built using brushes, Static Meshes can be used to create complex, intricate architecture that brushes are too coarse to emulate. Because Static Meshes are loaded into memory only once, even if used multiple times throughout a level, they are a more efficient way of using computer resources. Along with the fact that they can be considered as prefabs, Unreal Tournament 3 features static meshes almost exclusively.
Kismet is a gameplay
scripting
tool for the Unreal Engine 3, the game engine
developed by Epic Games
. It enables level design
ers to create scripts in UnrealScript
for gameplay events using a visual interface
.
and 3dsMax into UnrealEd.
Level editor
A level editor is a software tool used to design levels, maps, campaigns, etc and virtual worlds for a video game. In some cases the creator of a video game releases an official level editor for a game, but other times the community of fans step in to fill the void...
used to create levels
Level (computer and video games)
A level, map, area, or world in a video game is the total space available to the player during the course of completing a discrete objective...
for Unreal
Unreal
Unreal is a first-person shooter video game developed by Epic MegaGames and Digital Extremes and published by GT Interactive in May 1998...
. It was also used for other games based on the Unreal engine
Unreal Engine
The Unreal Engine is a game engine developed by Epic Games, first illustrated in the 1998 first-person shooter game Unreal. Although primarily developed for first-person shooters, it has been successfully used in a variety of other genres, including stealth, MMORPGs and RPGs...
, such as Deus Ex
Deus Ex
Deus Ex is an action role-playing game developed by Ion Storm Inc. and published by Eidos Interactive in 2000, which combines gameplay elements of first-person shooters with those of role-playing video games...
and Lineage II
Lineage II
Lineage II is a massive multiplayer online role-playing game for Microsoft Windows. It is a prequel to Lineage, and is set 150 years before the earlier game. It has become very popular since its October 1, 2003 launch in South Korea, reporting 1,000,918 unique users during the month of March 2007...
, although it has changed along with the engine for later games. One of the first companies to do this with first person shooters, all Unreal games on the PC
Personal computer
A personal computer is any general-purpose computer whose size, capabilities, and original sales price make it useful for individuals, and which is intended to be operated directly by an end-user with no intervening computer operator...
had the level editor
Level editor
A level editor is a software tool used to design levels, maps, campaigns, etc and virtual worlds for a video game. In some cases the creator of a video game releases an official level editor for a game, but other times the community of fans step in to fill the void...
included for free, and some third party Unreal engine games did the same with an edited and specialized version. This extended the longevity of the games. Amateur level designers could now create their own levels for the game, providing a near endless amount of additional content for the game. In addition, the built-in scripting language
Scripting language
A scripting language, script language, or extension language is a programming language that allows control of one or more applications. "Scripts" are distinct from the core code of the application, as they are usually written in a different language and are often created or at least modified by the...
called UnrealScript
UnrealScript
UnrealScript is the scripting language of the Unreal Engine and is used for authoring game code and gameplay events....
allowed for editors to customize game content.
UnrealEd has a customizable user interface
User interface
The user interface, in the industrial design field of human–machine interaction, is the space where interaction between humans and machines occurs. The goal of interaction between a human and a machine at the user interface is effective operation and control of the machine, and feedback from the...
, but the most common is the quad viewports with the top view in the top left, then, moving clockwise, the front view, the side view, and the perspective view. It has a row of buttons along the top pertaining to various options such as save, open, and rebuild, and a series of buttons to the left of the viewports which access editing functions.
Versions
With the various Unreal games, UnrealEd itself has seen many different versions. UnrealUnreal
Unreal is a first-person shooter video game developed by Epic MegaGames and Digital Extremes and published by GT Interactive in May 1998...
shipped with UnrealEd 1.0, which displayed most of the editing tools on a single large left bar adjacent to the four viewports. This version was extremely buggy
Software bug
A software bug is the common term used to describe an error, flaw, mistake, failure, or fault in a computer program or system that produces an incorrect or unexpected result, or causes it to behave in unintended ways. Most bugs arise from mistakes and errors made by people in either a program's...
, particularly while rebuilding maps.
Unreal Tournament
Unreal Tournament
Unreal Tournament is a futuristic first-person shooter video game co-developed by Epic Games and Digital Extremes. It was published in 1999 by GT Interactive. Retrospectively, the game has also been referred to as UT99 or UT Classic to differentiate it from its numbered sequels...
also shipped with UnrealEd 1.0, and UnrealEd 2.0 being added in a later game patch. The editor underwent a major visual change from the previously colorful buttons to a more subdued green scheme. New tools and features were added (such as search capabilities and a new 2D Shape Editor), and it also underwent a significant stability
Robustness (computer science)
In computer science, robustness is the ability of a computer system to cope with errors during execution or the ability of an algorithm to continue to operate despite abnormalities in input, calculations, etc. Formal techniques, such as fuzz testing, are essential to showing robustness since this...
upgrade
Upgrade
The term upgrade refers to the replacement of a product with a newer version of the same product. It is most often used in computing and consumer electronics, generally meaning a replacement of hardware, software or firmware with a newer or better version, in order to bring the system up to date...
, and though the editor still had its share of strange crash
Crash (computing)
A crash in computing is a condition where a computer or a program, either an application or part of the operating system, ceases to function properly, often exiting after encountering errors. Often the offending program may appear to freeze or hang until a crash reporting service documents...
es, it wasn't nearly as particular as UEd 1.0. There are also some bugs
Software bug
A software bug is the common term used to describe an error, flaw, mistake, failure, or fault in a computer program or system that produces an incorrect or unexpected result, or causes it to behave in unintended ways. Most bugs arise from mistakes and errors made by people in either a program's...
like the movers' collision (they block the bullets and they use to be like invisible walls) and the white screens (that you aren't able to see the 3D and the 2D screens)
Bundled with Unreal Tournament 2003
Unreal Tournament 2003
Unreal Tournament 2003 or UT2003 is a first-person shooter video game designed mainly for multiplayer gaming. The game is part of the Unreal franchise's series of games, and is a sequel to Unreal Tournament ....
was UnrealEd 3, with further increased stability. It maintained the green colors, and looks virtually identical to UEd 2.0. The editor added a static mesh
Static Mesh
Static meshes are polygon meshes which constitute a major part of map architecture in Unreal Engine and many other engines like Source. The word "static" refers only to the fact that static meshes can't be vertex animated, as they can be moved, scaled, or reskinned in realtime.Static Meshes can...
browser to support static meshes (known as "hardware brushes" during development), and combined the various browsers into a single browser with tabs to switch between textures
Texture mapping
Texture mapping is a method for adding detail, surface texture , or color to a computer-generated graphic or 3D model. Its application to 3D graphics was pioneered by Dr Edwin Catmull in his Ph.D. thesis of 1974.-Texture mapping:...
, meshes
Polygon mesh
A polygon mesh or unstructured grid is a collection of vertices, edges and faces that defines the shape of a polyhedral object in 3D computer graphics and solid modeling...
, actors, etc.
Future versions of UnrealEd will be fully backwards compatible with content developed under previous versions.
Basic premise
UnrealEd operates on the concept of brushesBrush (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...
. Additive brushes can be solids, semisolids or nonsolids. Generally, brush geometry was used before Unreal Engine supported the use of static mesh
Static Mesh
Static meshes are polygon meshes which constitute a major part of map architecture in Unreal Engine and many other engines like Source. The word "static" refers only to the fact that static meshes can't be vertex animated, as they can be moved, scaled, or reskinned in realtime.Static Meshes can...
es. Ever since static meshes could be placed in a level, brush geometry tends to be less used and is generally discouraged.
Older versions of UnrealEd treated the world as a giant mass, from which the level designer subtracted space, in order to make the level walkable and, therefore, playable. Since UT3, UnrealEd can start with either a full, subtractive space (from which the designer subtracts geometry) or an empty, additive space (to which the designer adds geometry).
Some brushes may be movable or special brushes: such a denotation gives game designers, level designers, and level editors the ability to create moving objects within a game. These special types of brushes may be used to create waterfalls, elevators, flying carpets, doors, drawbridges, and many other types of dynamic objects. Zones can be denoted within the various brushes—after the brush has "sculpted" an area of space within the virtual 3D
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...
environment (or level) -- effectively creating wet zones, sky zones, dry zones, or fog zones. In this way, lakes or pools can be created, interiors of buildings or exterior terrain and landscapes. Day or night may be created, through the use of "skyboxes" and other tools in the editor. Weather may be assigned to various levels or zones, allowing such features as snow, rain, or clear weather.
The basic process of CSG operations
Constructive solid geometry
Constructive solid geometry is a technique used in solid modeling. Constructive solid geometry allows a modeler to create a complex surface or object by using Boolean operators to combine objects...
within UnrealEd is markedly different from other computer game editors that treat the world as a giant space, such as Quake and Quake II
Quake II
Quake II, released on December 9, 1997, is a first-person shooter computer game developed by Id Software and distributed by Activision. It is not a sequel to Quake; it merely uses the name of the former game due to Id's difficulties in coming up with alternative names.The soundtrack for Quake II...
game level editors. In those and similar game editors, brushes are initially added to the vacant space within the game's 3D
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...
environment in order to create virtual terrain and architecture within the level currently being edited. Both subtractive-based computer game editors (such as UnrealEd) or additive-based computer game editors (such as Qoole) may each produce stunning 3D computer graphics
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...
for the gameplayer. Yet, each type of editor functions in nearly diametrically-opposed manners. Each type of level editor has its own advantages and disadvantages. The subtractive-based computer game editor was developed after the additive-based computer game editor.
In UnrealEd, brushes are used to compile a level into a BSP Tree
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...
for rendering and collision detection. Unfortunately, as levels become more complicated they are prone to BSP errors, resulting in visual and collision anomalies. There are several types of BSP errors: BSP holes and hall of mirrors are two common forms. BSP errors can be very difficult to correct. This is partially why the use of Static Meshes was introduced in the Unreal 2 Engine.
Static Meshes are pre-created Polygon mesh
Polygon mesh
A polygon mesh or unstructured grid is a collection of vertices, edges and faces that defines the shape of a polyhedral object in 3D computer graphics and solid modeling...
geometry, created in software such as Maya
Maya (software)
Autodesk Maya , commonly shortened to Maya, is 3D computer graphics software that runs on Microsoft Windows, Mac OS and Linux, originally developed by Alias Systems Corporation and currently owned and developed by Autodesk, Inc. It is used to create interactive 3D applications, including video...
or 3D Studio Max
3D Studio Max
Autodesk 3ds Max, formerly 3D Studio MAX, is for making 3D animations. It was developed and produced by Autodesk Media and Entertainment. It has modeling capabilities, a flexible plugin architecture and can be used on the Microsoft Windows platform. It's frequently used by video game developers, TV...
, that can be imported and positioned within levels. Although a level's foundation and basic layout is still built using brushes, Static Meshes can be used to create complex, intricate architecture that brushes are too coarse to emulate. Because Static Meshes are loaded into memory only once, even if used multiple times throughout a level, they are a more efficient way of using computer resources. Along with the fact that they can be considered as prefabs, Unreal Tournament 3 features static meshes almost exclusively.
Kismet
Gameplay
Gameplay is the specific way in which players interact with a game, and in particular with video games. Gameplay is the pattern defined through the game rules, connection between player and the game, challenges and overcoming them, plot and player's connection with it...
scripting
Scripting language
A scripting language, script language, or extension language is a programming language that allows control of one or more applications. "Scripts" are distinct from the core code of the application, as they are usually written in a different language and are often created or at least modified by the...
tool for the Unreal Engine 3, the game engine
Game engine
A game engine is a system designed for the creation and development of video games. There are many game engines that are designed to work on video game consoles and personal computers...
developed by Epic Games
Epic Games
Epic Games, Inc., also known as Epic and formerly Epic MegaGames, is an American video game development company based in Cary, North Carolina. Its most recent success has been the Gears of War series of games, although it is also known for its Unreal Engine technology. It is the parent company of...
. It enables level design
Level design
Level design, environment design or game mapping is a discipline of game development involving creation of video game levels—locales, stages, or missions. This is commonly done using level editor, a game development software designed for building levels; however some games feature built-in...
ers to create scripts in UnrealScript
UnrealScript
UnrealScript is the scripting language of the Unreal Engine and is used for authoring game code and gameplay events....
for gameplay events using a visual interface
Graphical user interface
In computing, a graphical user interface is a type of user interface that allows users to interact with electronic devices with images rather than text commands. GUIs can be used in computers, hand-held devices such as MP3 players, portable media players or gaming devices, household appliances and...
.
Building designers adopt UnrealEd
In an effort to provide realtime walkthroughs of their proposed buildings, with gravity and impact detection, building designers have begun to build models inside UnrealEd to test out their ideas. By allowing the public to pretest a building, a better result can evolve prior to construction. One problem persists however, which is the conversion of element sizes from design programs such as AutoCADAutoCAD
AutoCAD is a software application for computer-aided design and drafting in both 2D and 3D. It is developed and sold by Autodesk, Inc. First released in December 1982, AutoCAD was one of the first CAD programs to run on personal computers, notably the IBM PC...
and 3dsMax into UnrealEd.
External links
- Unreal Developer Network, Epic's own website on editing the Unreal engine
- UnrealWiki, containing hundreds of articles on UnrealEd
- Hourences' tutorials
- Game Developer Conference '06: Epic shows off Unreal tools
- Stanford: UnrealEd for Education