[Runtime Issue]: Mercenary game assets confusion

[JeodC]

Build Version

current

Operating System Environment

• Microsoft Windows (32-bit)
• Microsoft Windows (64-bit)
• Mac OS X
• Linux (specify distribution and version below)

Description

The game will check for the existence of Mercenary expansion via registry string. If it doesn't exist, the Black Pyro ship is supposedly unable to be selected at Pilot->Configure (after passing Merc Level 2). #254 attempts to fix that, but Merc assets still failed to load from the steam version of the game where they are located in extra.hog.

Only after installing the CD-ROM, installing the Merc CD, then patching to 1.4, can the game function as expected by copying merc.hog and EXTRA.HOG (renamed to extra.hog) to the other install directory.

In essence #254 is only a partial fix. The underlying cause of this bug is unknown.

File breakdown:

EXTRA.HOG contains the following:

merc.hog contains a lot more:

In comparing the two, it appears the steam release extra.hog is a copy of merc.hog, and EXTRA.HOG from the CD is missing entirely.

[JeodC]

In the digital releases, merc.hog is renamed to extra.hog, and EXTRA.HOG is renamed to extra1.hog.

[Jayman2000]

The underlying cause of this bug is unknown.

I actually think that this is intentional, and I think that I know the underlying cause. I believe that this chunk of code is what causes the behavior, but I haven’t tested it yet.

Only after installing the CD-ROM, installing the Merc CD, then patching to 1.4, can the game function as expected by copying merc.hog and EXTRA.HOG (renamed to extra.hog) to the other install directory.

Here’s the mechanics of how installing Descent 3: Mercenary via CD fixes the issue. The Descent 3: Mercenary CD has a file in its root directory named AUTORUN.INF. Here’s the contents of that file:

[autorun]
open=setup.exe -autorun
icon=Descent3AutoRun.ico

That AUTORUN.INF file will make it so that when the CD is inserted, older versions of Windows will automatically run setup.exe -autorun. If you run the installer without the -autorun option, then it won’t create the …Uninstall\Descent3 Mercenary registry key.

I believe that this is a crude form of DRM. If you were to download the files illegally from the Internet, then AUTORUN.INF probably won’t get used because you probably won’t bother putting the files onto a CD. If AUTORUN.INF doesn’t get used, then the -autorun parameter probably won’t get used which means that the …Uninstall\Descent3 Mercenary registry key won’t get created. If those registry keys don’t get created, then Descent 3 will refused to load some of Descent 3: Mecenary’s content.

[JeodC]

That is only part of the issue. See the latest commit in the PR. Still testing.