World Building 101
Fallout 3 world building for the PC is a relatively challenging process that is both extremely difficult but very engaging, satisfying, and fun to use. World building in the video game Fallout 3 is still relatively straight forward, though your first project will take about three hours to complete, depending on your computing background computers.
You will need a few programs in order to complete the job and make it possible for you to use Fallout 3's world building interface. You will need the Fallout 3 game in order to do this job and the GECK, Garden of Eden Creation Kit, which can be downloaded at geck.bethsoft.com, and then installed in your Fallout 3 directory. Don't worry if you happen to receive a "libvorbilfile.dll" error, this just means you have put the file in the wrong place and need to delete it and download it again.
Information and data on the GECK can be read and uploaded at the official GECK wiki at snipurl.com/9ohko and the Bethesda basic tutorials in text and video form at snipurl.com/9ohlp. The official mod forum for GECK can be found at snipurl.com/9ohmb.
Downloading the GECK
After you have downloaded the GECK at the link above, opening the existing Fallout 3 content is necessary, so you can start editing the content. In order to do this, head to File > Data and then double-click Fallout 3.esm on the list that appears. Now, select Okay to fill all the Fallout 3 locations. The next thing to do, before were able to start creating our new world, is to save your project so that you have a file to put all your stuff into. This is accomplished by selecting File > Save and then give it an unforgettable name.
A different reality
You can't actually change Fallout 3's main file, it won't allow this to happen. Instead, the GECK makes plug-ins that you can turn on or off using the handy launch screen that appears just prior to the game starting. Using this screen you can add content, play with the existing stuff, or completely change the areas that already exist without altering your original game. It's not a good idea to save with a mod activated and then later load with it turned off because you will receive a warning message that will tell you things might be a little off the wall. Instead create a new profile or at the very least a new character, and this way you should avoid destroying your work.
Making a vault
The safest and quickest way to create a new area is to copy one that is already made. The Vaults are the easiest to make, and lots of them already exist. Check out the Cell View, making sure you have chosen Interiors (external wasteland areas are handled differently, using height-maps for terrain) and choose one to use, just right-click on it and select Duplicate Cell. The new cell should show up beneath the old on, with COPY0000 as its name. Left-click it a few times and then choose a new ID, you can pretty well use anything you want too, but make it something you will easily remember. Now, select Edit, and open the Interior Data tab to give it a new title.
Clean the slate
Once the map is loaded all its components show up on the right of the Cell View panel. Clean things up using select all the objects in the list, and then click Delete. You will have a clean slate, but with stuff like the lighting settings left in place. Before adding things, select Snap To grid located on the top bar, and travel through the Object Window to Static > Dungeon > Vault. Now, create an Overseer's Office (VRmOverseerOffice01) by dragging it into the 3D window.
Turning the lights on
The screen window will be black when it first appears, but not to worry. Press A and the lights will magically turn on in the editor. You will need to move around the editor to get a better view (or to find the room if you can't presently see it) using the mouse wheel to zoom in and out and move the mouse while holding Shift to rotate the picture.
Putting things in place
The Overseer's Office interface can be a little complicated, with a group of parts you'll need to put together to have it work properly. Import CG04OverseersTerminal and VRmOverseerOfficeDesk01 — type in the Filter Field in the Objects window to search for things to import. Just drag the terminal over to finish the back wall, and slide the desk to cover the secret passage in the floor. The best way to add them to the screen is to double-click on them, and carefully nudge them into place using the 3D Data tab.
The corridors of power
You can build a short corridor leading out of The Overseer's office using parts from Static/Dungeon/Vault/Halls. You can drag them out just like the office parts and just snapped them into place. Pay attention to the names of each piece as their designations indicate their jobs — "V" for "Vault", 3Way for "exits in three directions, ect. If you want to preview them, right-click the one you want to look at and select choose Preview to take a look at them individually. To connect them, use Snap To Grid and place one in position, press CTRL-D and it will be duplicated or select CTRL-F to change it into a different part.
Lots of stuff
The true Fallout feeling requires lots of stuff everywhere, so you will want to add things. This is such an important point that they have added a dedicated tool for scattering stuff around — the Object Palette, located in the World menu. Just drag in stuff you want to use from the left-hand panel. Use the + and – boxes to determine the amount of random spin or size for each item you put in place. To put one in position, left-click it in the 3D view while holding down Ctrl and Alt. The selected part will automatically snap into position beneath the cursor, on the first available surface, instead of hanging in the air.
The individual parts have properties and such that you can change and play with, whether they're containers or NPCs. NPCs are a complicated item to code for, but altering a file cabinet is as simple as playing with its inventory pack. Just choose one from the Object Window, like FilingCabinetEmpty, and place it where you want. If you want to take a look at its properties, double-click it and they will appear, and then select Edit Base. Now, name it a custom ID, anything will do, but make it something you will remember, and then right-click it in the Item List, and select New. Choose an object to be put in the cabinet and press OK to save the whole thing as a new Form. Please just ignore the different setting for the moment.
Keeping the door closed
Now, it's time to connect our micro-vault to the larger Fallout world. Add a HallEndDoorway block to a corridor and an actual door to go in it. Open one of the Wasteland cells and choose an already available door from the Wasteland. Double-click it, select the box marked Teleport if it isn't selected already and then choose VaultPCG. There's only one door to choose, so select it. The GECK will take care of the return path, if you end up on the wrong side when you use it in-game, just rotate the door.
Message in a bottle
Now that we've come this far, we need to let the world know where you have gone. Type the text "Holotape" into the Object Window's filter box. Next, drag the Vault112Holotape item into the level and double-click on it to bring up its properties. The first thing to do is to change the Base Object's name, which will allow us to implement the Holotape's features without overwriting what's already there. Name it "Dear Searcher", with the ID "Dear Searcher", and ensure Note Type is set to Text. Were just about finished, last thing to do is to type your final message to your doomed brothers and sisters here, and leave it outside the door before entering and locking the door (marking it as inaccessible on the inside).