By Z8Fever
Like many other RTS's, Homeworld stores a good deal of its data outside the homeworld.exe file. For most basic modifications, this is the stuff we really want to get at. This info includes the models, animations, textures, and other attributes of ships, weapons, GUI's, and other elements of the game. Most of this data is stored within compressed files that end in .big. BUT, it doesn't need to be there. In fact, for most editing purposes, you can mimic the .big's structure in your Homeworld directory. The order in which Homeworld searches for the external data it needs is:
1.) In the same directory as the .exe file
2.) In the UPDATE.BIG file
3.) In the HOMEWORLD.BIG file
FIRST STEPS
To do any real editing to Homeworld, you must first extract the files you need from either the homeworld.big or the update.big file. If you know exactly what you want to change, you can extract just those files, but for most people, it is much easier to extract the entire .big archive into a directory set up just for that purpose (This will save much time - the BIG Viewer can take up to 30 minutes or more to load the Homeworld .big file). However, you should only take this approach if you have ample hard disk space - the extracted Homeworld.big is 101 Mbytes even though Update.big is only 1.05 Mbytes. Here's what you do:
1.) First, download the BIG Viewer (258 Kbytes) and unzip. You will be downloading many editing programs that don't "install" because they are small, simple, single-purpose, third party apps, so it doesn't hurt to set up a "Homeworld editing" directory to store your Homeworld related downloads, programs, documentation, and source when you begin to download your first files for editing.
2.) Once you run the BIG Viewer, you will see a screen similar to this:
Click on "Load Big File" button, or "file", then "Load Big File". Locate either your homeworld.big or update.big file and click "open". With the homeworld.big file, this could take longer than 45 minutes on a very slow computer, so be patient. The update.big file can be opened in a matter of seconds, however, so it is good to start off with that. As you can nwo see, the left pain contains an outline of the file's contents, denoting directories containing other directories with +'s or -'s, depending on whether they have been opened. By clicking on a file in this pane, the right is activated, showing the contents of the file if it contains ASCII text or if it is a .lif file (a texture, in which case you may have the option of viewing the graphic).
3.) The next step is to extract your files. There are 3 different ways to do this, all of which work slightly differently. To extract only 1 single file, click on it in the left pain and then click the "Save File" button or "File", "Save File". However, if you do this with a directory, it will only save one file from that directory. To extract an entire directory and all of it's daughter files and directories, use the save recursive function (This will also keep the directory structure intact). Select the directory you wish extract and click "File", "Save Files (Recursive)". Now, if you're thinking ahead, you'll realize that if you click on the the entry in the left pain with the name of the file you have open (homeworld.big or update.big) and extract that recursively, you will extract the entire contents of the .big file. The last kind of extraction to perform is the Save List function. Click "File", "Save List". This will export a text file listing the contents of the .big file you are currently viewing. However, do not do this if you are planning on extracting the entire .big file, because within it is contained another copy of the contents list.
Editing Data and Seeing the Changes in Homeworld
After you've extracted the .big file, you're ready to edit. Copy the files you want to mess with and move them to the Homeworld directory as if it was the .big file. For example, if I were editing tweak.script, which is located in the root of homeworld.big, I would copy the file directly into my Homeworld directory. If I were editing Lightinterceptor.ship (Scout), which is located in homeworld.big --> r1, I would copy the file into a directory named r1 in my Homeworld directory. Now, when Homeworld searches for these files on startup, it will find them there first and thus bypass their copies in the two .big files. You can now edit these 2 files to your liking and run Homeworld to see how your changes work.
Most of the files in homeworld.big and update.big can be edited with a simple graphics editor or a text editor, such as Windows's Notepad. .shp files control ships' attributes (r1 directory is Kushan and r2 is Taiidan), .lif files are textures and must be converted to another format to edit (or you can change pixels one at a time with LIF Edit), .peo and .geo files are the meshes for ships, .script files are all kinds of random things, and others will be discussed in a later tutorial. For now, most parameters are pretty self-explanatory, but if you need help or want to help others in that area, pick up the Shadetree's HWIE and help index all of them. Also, check out the downloads for helpful utilities out so far to help edit all kinds of the files contained in the .big file. Remember: if you ever have any specific questions that you can't find the answer to, first look at Relic's Editing Message Board, and if you still can't find out, don't be afraid to e-mail me or anyone else who seems fairly knowledgeable -- We would love to help you out, especially if we don't know the answer -- it gives us an excuse to go figure out something more. HAVE FUN!