This document covers a very brief description on how to operate the editor and lists key concepts to be kept in mind at all times when using UnrealEd 3.0.

Bring this document with you to all workshops until you feel comfortable with the layout of the editor, have a good idea what most of the buttons/functions do, and have fully grasped the major concepts of constructing geometry.

UnrealEd offers users a very visual based method of building 'Unreal Engine' game levels hereafter referred to as 'Maps' as this is the correct term when addressing a 3D level in its purest form.

Key Concepts and Terms

If you have never worked in 3D space before, it's important that you are aware of a few key concepts before proceeding.

3D Space allows you to place objects on a plane to create the illusion of perspective. Artists attempt to create this illusion when, say, painting a picture of a landscape with a tree in the foreground and mountains in the background. The tree the artist paints appears much larger than the mountains in the background even though we know that in reality the mountains are much larger than the tree. Another example is looking down a set of railroad tracks. If you stand in the centre of the tracks and look off in the distance in the direction of the tracks, the tracks appear to meet at a point even though we know railroad tracks are parallel. This illusion is known as convergence-related distortion.

In UnrealEd, you create this illusion of convergence by placing objects in 3D space. Convergence distortion will only appear in the 'Perspective' viewport, and closely relates the view as it will appear in the game. This is the viewport that shows both the object as a solid form and in the correct perspective. The viewports labelled 'Top', 'Front', and 'Side' are known as orthographic viewports.

The orthographic views cover the technical layout of your world space. All the wireframes travel perpendicular to each other and project onto a single plane rather than converging at an apex as in the 'Perspective' view. What this means is that regardless of position in 3D space, all the objects in the orthographic views will appear the same size without convergence-related distortion. As we work more with the editor, it's important to keep these concepts in mind as it will aid you in the correct placement of objects in your world.

For those of you who have worked with 3D space before (for example 3D Studio Max, Lightwave or Maya) there is a major difference in how UnrealEd works with regard to building geometry in its 3D space. In most 3D modelling packages you start with an infinitely big open space in which you can add solid objects to your scene or world. In UnrealEd the opposite is true. A user starts with a very large solid block, big enough to make very large scaled outdoor environments, and in order for anything to be created inside this block, there first must be a hollowing or 'subtraction' made to the block in order to give the user some open space in which to 'add' their solid geometry. Note the words 'add' and 'subtract', you will be hearing these a great deal when you start building work with the editor.

This may seem like a strange concept but we have to remember that while applications such as 3D Studio Max have no limit on how and where you place your geometry, games engines have to render what the player sees on their screens in excess of 24 times per second! Keeping geometry inside manageable boxed areas helps keep the workload of the system render device consistent and fluid.

Whilst on the subject of building, there is another concept, unique to UnrealEd that requires mentioning. To actually place a primitive in your 3D space involves three separate steps. Firstly you choose the dimensions for the primitive and click the 'Build' button (see 'Primitives' section). That sounds straight forward enough, but wait, nothing has changed. By doing this you have told the editors 'Active brush' what shape to take (see 'Brushes and the 'Active Brush'' section). To actually get the shape to appear in your 3D space you need to perform a CSG operation on it (see 'Adding and Subtracting brushes' section). Then, to complicate matters even further, you have to 'rebuild' your level to ensure its correct inclusion. The whole process sounds vastly overcomplicated but I assure you that it is necessary, and when you are used to it, you won't want to build any other way! 

One final thing to bare in mind is the complexity and the amount of geometry contained within your map directly affects the users experience with regard to onscreen output.  

Now the potentially off-putting techno-babble is over, we can open UnrealEd 3.0 and see what all the fuss is about.

Opening UnrealEd 3.0 and exploring the Interface

Go ahead and open UnrealEd. You will be presented with the screen that looks similar to the one below.

Note: If you have a white space where the viewports should be, click on 'View > Viewports > Configure…' then, when the dialogue box appears, click 'OK' and they should reappear. 

You can also use this option to change the viewport configuration if you are used to something else or fancy a change. However, all the screenshots used in the workshop handouts will be based on the above (default) configuration, so only change it if you feel comfortable keeping track.

If you wish to resize the configuration click on 'View > Viewports > Floating'. This places each viewport in its own, re-sizeable window. Arrange them how you wish. To make them fixed again simply click on 'View > Viewports > Fixed'. UnrealEd remembers the last locations and configuration on the viewports when it is started. If at any time you wish to revert to the default sizes/locations, follow the instructions in the above paragraph.

The Interface

When the first screen appears, you are presented with four viewports you will use to create and position the objects in your map. As described earlier, the three viewports labelled 'Top', 'Front', and 'Side' are the orthographic viewports. All the objects visible in the orthographic viewports appear as wireframe and without convergence distortion. The 'Perspective' viewport (labelled 'Textured' in the image above) is where you'll see each object placed in the correct perspective and textured.

This document is meant as a gentle introduction to UnrealEd 3.0 so with this in mind, I won't cover the majority of the buttons on the interface except those that relate to the workshops that you will soon start. For more specific information related to each button, see the 'More Help' section at the end of this document. If at any time during the workshops a new method of working is introduced that includes the use of a button/function not covered here, there will be a description of what that button/function does prior to its use.

The most widely used buttons are the 10 Primitive Objects, the CSG (Constructive Solid Geometry) operation buttons, the browsers, and Build.

Primitives

In order to create objects in your map, you need to have something to work with, that is, you need to have primitive geometry to build upon. The Primitives at the simplest level are the Cube, Cone, Cylinder, Sheet, and Sphere. Also included in the UnrealEd primitives are BSP Based Terrain, Volumetric, Linear Staircase, Curved Staircase, and Spiral Staircase. Each of these buttons will allow you to create the objects for addition or subtraction in your 3D space. In order to define the properties for each object, right-click on the object you wish to create to bring up a window where you can enter in such parameters as length, width, and breadth along with additional parameters related to the specific object.

For instance, right clicking on the 'Cube' button will bring up a window like the one below.

In this window, you can enter in the specific parameters related to the brush you wish to create. In this case, a cube with the size (Height) 256 x (Width) 256 x (Breadth) 256 will be built if you click on the 'Build' button. One thing to note, however, is that 'Build' in UnrealEd terms doesn't mean a space is created for the player to run around in. Clicking 'Build' only resizes the red 'Active Brush' for later addition or subtraction in your world space. This concept is explained in full in the 'Brushes and the 'Active Brush'' section later on in this document.

Any geometry that is featured in the 3D space will be hereafter referred to as a 'brush', named appropriately as an artist uses a brush to create a picture, UnrealEd uses brushes to create a map.

CSG Operations

The next set of buttons up for discussion are the 'CSG Operation' buttons. These are the buttons you will use to create the geometry of your map after you define the parameters as outlined above. The buttons are (from top left) Add, Subtract, Intersect, De-intersect, Add Special, Add Static Mesh, Add Mover, Add Anti-Portal, and Volume. You will want to familiarize yourself most with the Add and Subtract buttons. The 3D space in UnrealEd is subtractive space, meaning that in order to create the world of your map, you have to first subtract the space. Think of it as carving out sections of a huge clay block.

The name CSG means 'Constructive Solid Geometry' and this in turn refers to the carving (subtracting) and adding of brushes to the 3D space to build a map. Brushes are covered in more detail in the 'Brushes' section further on in this document.

Furthermore, the 'Intersect' and 'De-intersect' buttons play an important role in maintaining the integrity of your BSP, or 'Binary Space Partition' in that they carve out sections of a brush to fit perfectly in your world space. The concept of BSP is beyond the scope of this document. For more information on BSP and the BSP Tree, see the 'More Help' section at the end of this document.

The 'Add Special' and 'Add Mover' buttons are used to add specific objects to your level. Clicking 'Add Special' calls up a separate window from which you can create brushes for portals, zone portals, and mirrors among other things. Again, we won't be covering many of these items in the forthcoming workshop. The 'Add Mover' button is used to create geometry that moves such as a door or geometry that moves a player from one point to another, such as a lift.

Finally, the 'Add Volume' Button is the last we'll cover in this toolset. 'Add Volume' is used to create space for water, lava, or other liquid as well as additional options. In the forthcoming workshop, we'll touch briefly upon water and lava and leave the others for an additional workshop.

Browsers

The browsers in UnrealEd are where you will find all the non-geometry related objects (with the exception of 'Static Meshes' as they are geometry, but they don't affect the BSP geometry of the map). Starting from the left, these browsers are Actors, Group, Music, Sound, Textures, Mesh, Prefab, Static Mesh, and Animation. As you build your maps you'll likely become most familiar with the Actor, Sound, Textures, and Static Mesh browsers. Each of these buttons call up a new window from which you can choose items to place in your level. The 'Actor' and 'Texture' browsers will be discussed most in the forthcoming workshop with a brief familiarisation on a few of the others.

Build

The last set of buttons we will discuss are the 'Build' buttons. Starting from the left are Build Geometry, Build Lighting, Build Changed Lighting, Build Paths, Build Changed Paths, Build All, and Build Options.

The 'Build Geometry' button, as expected, simply builds the geometry. That is, if you subtract, add, or move a brush in your map, it will create (or recreate) the geometry in your map. 'Build Lighting', and its partner 'Build Changed Lighting', simply updates the lights in your world. 'Build Paths' and 'Build Changed Paths' are only needed once you've laid out a path network in your map, that is, the network that computer operated robots use to navigate through your level. 'Build All' encompasses the functions of the previous mentioned 'Build' buttons, rebuilding everything based upon the settings outlined in 'Build Options'. Lastly, the 'Build Options' button allows you to define the parameters on which the geometry, paths, and lighting are built. For our purposes, and for most of the purposes of level building with UnrealEd, it's best to leave the options at their default values.

The final button, 'Play Map!' (the joystick), is your best friend. Clicking this button starts up Unreal Tournament 2004 and allows you to play the map currently on display in the editor. A word of caution before you click this fabled button. Make sure you 'Build All' and 'Save' your map before you test it, as any changes, additions or subtractions since the last save will not be present in the version you will be presented with. Testing your map often is the key to good design. Find problems and correct them before proceeding with anything else.

Moving around the Viewports

The most unusual thing you will notice about UnrealEd is the way you move around the viewports. There are no navigation tools as in other 3D applications just the infinitely more useful and more productive navigation by mouse technique.

The mouse is used to pan and zoom in all the view ports. Here's how it's done:

In wireframe 'Orthographic' viewports:

• To pan (move), hold down the left* mouse button while moving up or down, left or right.
• To zoom, hold down both mouse buttons while moving up to zoom out, or down to zoom in.

*If you hold the right button while moving in any direction, the movement will be quicker. This is useful if you have to move across a large area of you level.

In the 'Perspective' viewport:

• To move up and down (z axis), hold both mouse buttons while moving the mouse up or down.
• To move around your level, hold the left mouse button while moving up, to move forward, or back to move backwards
• To rotate in the direction you whish to face, hold the left mouse button while moving the mouse left or right.
• To rotate up and down, hold the right mouse button and move up, to look up, or down to look down.

It takes some getting used to, but when you have mastered it, you will see how much more useful it is compared to applications that require navigation buttons.

Brushes and the 'Active Brush'

As this concept is quite different and unique to UnrealEd, this section is dedicated entirely to brushes. In UnrealEd you create a primitive by firstly creating a brush of that object. A brush is a wireframe representation of the object we wish to build with all the correct dimensions. The brush will then appear as the red wireframe 'Active Brush'. This brush is not committed to the world unless we tell it to do so, either by clicking the 'add' or 'subtract' to/from world buttons (see section below). This gives us the freedom to move, scale and rotate the brush until we are satisfied it is in the correct location and of the correct orientation, before committing it to the 3D space.

The more you use the editor; the more you will understand why this is so important.

There is only a single active brush, and that is always displayed in red. The brush you create will stay in your world even after you have committed it. It is always visible in the editor and only changes when you next build another primitive or change the sizes of the current primitive.

Adding and Subtracting Brushes

As mentioned earlier UnrealEd uses 'Constructive Solid Modelling' which is a 'subtractive' method of working with a 3D space. You start off with a huge solid block, and to create a level you must first carve (subtract) out the rooms/locations, you want and build them up by adding more and more brushes until you achieve the desired result.

The two most common buttons you will use in the editor are the 'subtract brush from world' and the 'add brush to world'. When the brush is committed to the world it is then displayed, textured, in the 'Perspective' viewport and is shown in the 'Orthographic' wire frame viewports in a special colour.

These colour's indicate what types of brushes have been committed to the 3D space. The most common types and their colour's are shown in the table below:

Brush Colour Description

Note that all brushes change colour when they are selected. The colour's above refer to a brushes unselected state. With the exception of 'Volume' brush, all brushes change to a brighter colour of their unselected colour when selected. Volume brushes change to a white colour when selected.

Even after a bush has been committed, it can still be moved, rotated and have any other transformation applied to it. The only difference being that all changes made to a committed brush are not updated in the 'Perspective' viewport until the level is rebuilt (see 'Build' section).

The only operation that has to be done to a brush AFTER it is committed is vertex manipulation. NEVER use your active brush for vertex manipulation, it distorts the brush and when adding or subtracting, it can create some undesirable effects. There will be a section dedicated to vertex manipulation in one of the forthcoming workshops. Read it before attempting any, even if you attempted vertex manipulation in another 3D application.

Moving brushes around your Map

When a brush is selected, it is a bright shade of its native colour (see table above) and is ready to be moved around the level for placement or relocation. To select a brush, click anywhere on its wire-frame (not inside the wireframe, you must select the line itself). It is usually easier to select wireframe's in one of the 'Orthographic' viewports.

Moving a brush around is similar to physically moving around the viewports. Here's how it's done:

• Hold Ctrl while holding the left mouse button and move the mouse up, down, left, or right to move it around the view port. Remember that each different viewport has different axis, so moving up or down in the 'Top' viewport moves the brush in a different direction than moving it up or down in the 'Side' or 'Front' viewports.
• Hold Ctrl while holding the right mouse button and move left and right to rotate it around its pivot. Again this has a different effect in each different viewport.
• If you need to move a brush out of the current scope of the screen, hold Shift while holding the left mouse button and move the mouse up, down, left or right and the screen will pan with the movement of the brush.

Brush Pivots

The pivot of a brush controls some important things. It controls the centre of any rotation and skew applied to it. It also controls its placement in the world. The brush will snap to the grid (see 'Grids, units and scale') in relation to the selected pivot of the brush. The pivot is shown on the brush as a cross on one of the vertices (vertices in UnrealEd are displayed as dots). By default, this is in the centre of the solid.

Although there is no actual vertex in the centre of a solid, UnrealEd creates a dummy centre vertex in any primitive so rotation around a brushes exact centre is possible.

The pivot of a brush can be any of the vertices found along its wireframe. To change the pivot point simply click on any of the vertices on the selected brush and the cross will be moved to that point. All the things the pivot controls will now be acted around the selected point until it is changed.

Brush Order

Think of brush order as being similar to layers in Flash or PhotoShop. The layer at the top of the stack has visual priority over those below it. The same is true in UnrealEd but the order in which the brushes were placed plays a more significant role than simple visuals.

When 'building' the map, the editor carries out the subtraction and additions to the geometry in the order in which they were created (from first to last). If you need to change the order a brush was placed, you will firstly, select the brush, then you right-click on the selected brushes wireframe. This brings up a menu which will be covered in the following weeks. Select Order and you have 3 options. 'To First' sends the brush to the first (or top of the stack). 'To Last' sends the bush to the last (or bottom of the stack). The third option 'Swap Order' works when you have 2 brushes selected. As its name suggests it simply swaps the order of the selected brushes. After any order changing you should 'rebuild' your map to reflect the changes in the perspective viewport. 

Grids, Units and Scale

Virtually every application you use on a computer has some form of grid and units options. Grids are useful for ensuring that objects are placed correctly and snap together for a clean professional finish.

In UnrealEd grids aren't just useful; they are essential and snapping to these grids should only ever be turned off if there is absolutely no other way of dealing with a situation.

The options selected by default when the editor starts are fine and shouldn't be messed with unless you really do have a good reason for changing them. Keeping all the geometry snapped together helps reduce excess work by the render device at runtime. Subtraction brushes especially might not cut up your world correctly if they are not snapped to the grid.

There is one option however that you should feel free to change as it will help when you are dealing with different scales of geometry and that is the 'Drag Grid Size' drop-down menu. For now will use the default value of '4' for the majority of our construction but if you ever include terrain in your map, setting the grid to higher setting is probably favourable.

As a rough guide:

• Grid settings 1 – 2 are useful for detailed placing of decoration objects (i.e. non-constructive geometry).
• Grid settings 4 – 16 are useful for human (Unreal Character) scale interior construction.
• Grid settings 32 – 256 are useful for small terrain maps and outdoor areas.
• Grid settings 512 – 4096 are useful for medium/large scale terrain maps and outdoor areas.

Snap To Grid

Introduction
This subject is basically intended for novices, since most l33t level designers always enable the Snap to Grid feature of the UnrealEditor. From experience mappers have noticed that UnrealEd operates much better when the Snap to Grid feature is on.
• Geometric brushes line up together perfectly
• Clean joins look professional during gameplay
• the 2D view is simpler & easier to understand
• reduced chance of BSP holes
• can result in a smaller filesize.
• eliminates having to make alterations after every level rebuild (I'm not sure what this means, but obviously means something – Tarquin )
• Allows Unreal to calculate occlusion factors faster and more efficiently.
• reduces occlusion time.
For snap to grid to do all of the above, it's important to do the following:
• Make the dimensions brushes multiples of the grid size. Eg 32, 64, 96, 128 etc.
• Never use the brush scaling tool to resize brushes. In UnrealEd 2 it's buggy and will increase your brush's dimensions by grid fractions. Use vertex editing mode instead.

Most importantly, when your brushes are aligned to the grid, that horror, BSP Holes are relatively infrequent, or totally absent from the map.

Grid snap is toggled with icon 4 (above) in UnrealEd's console bar. It's green if active, grey is inactive. Click it to toggle between the two.

You have probably noticed by now that there is a certain convention when creating brush dimensions. The use of numbers to the power of 2 ties in with the grid settings so it is essential you adopt this dimension convention to ensure that the brushes you create fit and onto the grid exactly. In construction, common figures used are 16, 32, 64, 128, 256, 512, 1024, 2048 etc.

As for scale, an Unreal Tournament 2004 character can stand inside a box (Height) 128 x (Width) 128 x (Breadth) 128 with a little bit either side for movement. The smallest space a player can squeeze into is 64 x 64 x 64. In order to get into a space this small a player must crouch and move at the same time (useful for ceiling vents, secret passages, etc.). If you are making spaces this small, try to give them tapered entrances and exits for fluid, uninterrupted transition. 

Unreal Tournament 2004's file and Package Structure

Every map you make will have a number of externally linked objects. Textures, as well as sounds, music and static meshes are all stored separately from your saved map. To begin with, we will be using textures and other objects that are included with the game; until you have the knowledge to create your own. Whilst this is the case, you don't need to worry about the objects you have used as their containing package has already been created and saved, it's when you start creating your own objects that you must understand the concept of packages.

Here is a diagrammatic view of the Unreal Tournament file system:

Maps (file extension .ut2) - These are the actual levels that we will create. The geometry of the map is stored here as well as positional information for static meshes and other actors. The BSP tree and light map that you create when you 'Build' you map is also stored here as are texture coordinates.

Music (file extension .ogg) - A single song is stored as an .ogg file. The old package for music was stored as a .umx file. Note that .ogg files can not be handled by the editor, but can be referenced. The old .umx packages can still be opened and saved inside the editor.

Sounds (file extension .uax) - A collection of sounds that have been imported into the editor for use in maps. These packages can be opened and manipulated inside the editor.

StaticMeshes (file extension .usx) - These packages are collections of models, usually imported from a 3D modelling package, and again, can have their contents manipulated inside the editor.

System (file extension .u) - Special scripts that perform non-standard actions can be written for your map and saved in this folder. Scripts can be opened and edited in the editor.

Textures (file extension - .utx) - A collection of textures that can be imported from various sources and manipulated to a certain extent inside the editor.

When the engine loads a map in the game, it also loads the packages containing the textures for the map, the music, the sounds, the static meshes and any specialised scripts from the folders above. Only the textures or sounds etc. that are used in the map are loaded to keep loading times down.

If you create a texture, for example, you must import it, save it into a new package (.utx) and include this package if you distribute your map or move it to another location (i.e. you computer at home). Failing to do so will result in the map not been able to load.

Editing the UT2004.ini file

You may notice that the editor takes a long time to load. By carrying out the instructions in this section, you can reduce this time by about three-quarters.

Upon startup, the editor loads in various packages that it feels it's users are mostly likely to need. There are a few essential packages that the editor requires to function, but the rest have no real need to be there, so we are going to stop them from being loaded when the editor starts.

As with any configuration changes, it's always advisable to back up the original file incase things didn't quite work. Make sure the editor is NOT running and open up the 'UT2004 > System' folder. Copy the file 'UT2004.ini' and paste it into the root 'UT2004' folder (or create another folder in the root and call it 'Original Files' or something).

Return to the system folder version of the file and open it. It should open with 'NotePad' but if not, you can set this up with the 'Open As...' function in Windows.

Scroll down to the [Editor.EditorEngine] section (use the 'Find' function in 'NotePad' and use 'editor' as search word). Towards the bottom of this section you will see a lot of lines starting with EditPackages. Delete all but the 6 shown below and you can delete all the lines starting with CutdownPackages.

EditPackages=Core
EditPackages=Engine
EditPackages=Fire
EditPackages=Editor
EditPackages=UnrealEd
EditPackages=IpDrv

Save the changes and restart the editor. It will load faster second time around anyway as it is still stored in RAM, but the next time you restart your computer and load the editor, you will notice a massive reduction in the loading time.

If your editor crashes on load, you have probably removed an essential package, and it should give you it's name in the error message. Replace the line or the original UT2004.ini if you are really stuck.

More Help

It is important to remember when you need to place objects such as weapons or pickups in your level to put the correct information into the 'Level Properties' options. Failure to do so will mean that objects that may appear fine in the editor, but will not appear in your level when launched.

The image below shows where this option can be found. To get to this option select 'View' then 'Level Properties' from the main menu bar in UnrealEd.

In this example we have set the DefaultGameType to the type suitable for a Deathmatch level.

The table below shows the appropriate types for the available games in Unreal Tournament 2004.

Helpful web sites:

The following links are to sites which deal specifically with Unreal map editing so feel free to explore these in your own time and take note of anything that seems relevant.

The official development website run by the creators of UnrealEd. This is the UnrealEd bible. Every aspect of the editor is covered here so I suggest you bookmark this site: http://udn.epicgames.com/

Specifically to the version of the engine will be working with: http://udn.epicgames.com/Two/WebHome

A list of what all the buttons do on the interface: 
http://udn.epicgames.com/pub/Content/UnrealEdInterface/

An unofficial (but technically accurate) guide to editing in UnrealEd:
http://www.birrabrothers.com/drac/ued2.html

From the above site, a description of how BSP works in UnrealEd (as previously mentioned in this document):
http://www.birrabrothers.com/drac/ued2_t041.html

There are 100's of web-sites dedicated to level creation in UnrealEd, so create your own list of URL's for reference.

Where now?

Although this document seems fairly sizeable, we have only covered the most essential topics raised by using UnrealEd. Some of the topics we have addressed still require further discussion in order to get the best out of the editor, but for now we have covered enough to get stuck in and start building our 'First Room'.