A base directory is a directory that Descent 3 expects game files to be in. When you run Descent 3, it will try to access many different files. Most of those files need to be stored in a base directory. There are two different types of files that are stored in base directories:
- Read-write files are files that can change while you play Descent 3. Examples: `<you name>.plt` and files in the `savegame/` directory.
- Read-only files are files that do not change while you play Descent 3. Examples: `d3.hog` and files in the `movies/` directory.
Descent 3 has two types of base directories:
- The writable base directory can contain both read-write files and read-only files. There is only one writeable base directory. By default, the writable base directory gets set to the current working directory.
- The read-only base directories can only contain read-only files. There can be any number of read-only base directories. By default, Descent 3 uses zero read-only base directories.
You can set the writable base directory and the list of read-only base directories using the `-setdir`, `-useexedir` and `-additionaldir` command-line options (see [the next section](#command-line-options)).
When Descent 3 tries to find a read-only file, then it will look through the list of base directories in this order:
- the last read-only base directory that was specified on the command-line,
- the second-to-last read-only base directory that was specified on the command-line,
- the third-to-last read-only base directory that was specified on the command-line,
- …
- the first read-only base directory that was specified on the command-line and, finally,
- the writable base directory.
Files that are in base directories that are higher on that list will override files that are in base directories that are lower on that list. For example, lets say that you run Descent 3 like this:
Let’s also say that both `my-writable-base-directory` and `my-read-only-base-directory` contain a file named `d3.hog`. In this example, Descent 3 will load `/home/user/my-read-only-base-directory/d3.hog` because read-only directories have a higher precedence than the writable base directory. Descent 3 will ignore `/home/user/my-writable-base-directory/d3.hog`.
The following command-line options are available in Descent 3. You can set command-line options on the Misc. tab of the Setup section of the Descent 3 launcher or by creating a shortcut to `Descent3.exe`. Case is not significant in command-line options, and `-`, `--`, and `+` are all accepted.
<td>Sets the time in seconds the a user must wait after sending an audio taunt before he or she is able to send another. This option is only active when starting a server.</td>
<td>Specifies a GameSpy configuration file to use.</td>
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<td><code>-httpproxy <addr></code> or <code>-httpproxy <addr:port></code></td>
<td>string</td>
<td>None</td>
<td>all</td>
<td>Specifies an HTTP proxy server. Descent 3 uses HTTP to auto-download a mission; use this option if your ISP requires a proxy server for HTTP connections. If the first form is used, the port value defaults to 80.</td>
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<td><code>-nooutragelogo</code></td>
<td>boolean</td>
<td>Off</td>
<td>all</td>
<td>Disables the Outrage logo that is normally displayed for five seconds at the start of a multiplayer game.</td>
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<td><code>-nomultibmp</code></td>
<td>boolean</td>
<td>Off</td>
<td>all</td>
<td>Disables sending or receiving in-game custom bitmaps for ships.</td>
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<tr>
<td><code>-nonetwork</code></td>
<td>boolean</td>
<td>Off</td>
<td>all</td>
<td>Disables all network multiplayer functionality.</td>
</tr>
<tr>
<td><code>-playermessages</code></td>
<td>boolean</td>
<td>Off</td>
<td>all</td>
<td>Disables all weapon-related HUD messages in multiplayer games.</td>
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<tr>
<td><code>-pxoport <port></code></td>
<td>integer</td>
<td>20142</td>
<td>all</td>
<td>Specifies the port that PXO will tell clients to use when contacting a server. The default is 2092.</td>
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<td><code>-useip <IP></code></td>
<td>string</td>
<td>All available network interfaces</td>
<td>all</td>
<td>Binds Descent 3 to this IP address. Use this option to tell D3 which IP address to use if your computer has multiple IP addresses.</td>
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<tr>
<td><code>-useport <port></code></td>
<td>integer</td>
<td>2092</td>
<td>all</td>
<td>Specifies the port that TCP/IP and IPX will use.</td>
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<tr>
<td><code>-usesmoothing</code></td>
<td>boolean</td>
<td>Off</td>
<td>all</td>
<td>Enables code to smooth the interpolation for fast-moving objects. This will fix "skipping" problems with fast weapons, such as the Phoenix. This option applies to clients only; using it on the server has no effect.</td>
