Copy Protection and multiple Scumm version installations

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MusicallyInspired
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Copy Protection and multiple Scumm version installations

Post by MusicallyInspired »

I have 3 versions of ScummVM installed. 0.9.0, 0.9.1, and the latest snapshot 0.10.0. All of them until well after this problem all use the same scummvm.ini file.

I had no problems a few days ago with playing any Scumm or otherwise game (including Ween) and bypassing the copy protection with all of these versions. Then suddenly that all changed.

I don't remember what it was that I changed to cause this to happen (I did change quite a few settings, like skins, paths, etc. The latest snapshot seems to be the only one capable of switching skins, incidentally, since the other versions don't have a "Misc" tab at the top in the main options menu), but now in both versions 0.9.1 and 0.10.0 Last Crusade EGA, Monkey Island 1 EGA, and Ween all need the copy protection to play the game. If you get them wrong it quits. If I play either of the first two in 0.9.0, however, it skips by the copy protection as normal. What's the difference? And what all the sudden is 0.9.1 and 0.10.0 not bypassing copy protection when they used to before?
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eriktorbjorn
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Re: Copy Protection and multiple Scumm version installations

Post by eriktorbjorn »

MusicallyInspired wrote: but now in both versions 0.9.1 and 0.10.0 Last Crusade EGA, Monkey Island 1 EGA, and Ween all need the copy protection to play the game. If you get them wrong it quits. If I play either of the first two in 0.9.0, however, it skips by the copy protection as normal. What's the difference? And what all the sudden is 0.9.1 and 0.10.0 not bypassing copy protection when they used to before?
I don't have any of these particular games myself so I can't see how they behave, but in general we try not to bypass the copy protection of a game unless we have permission from the original authors (e.g. the floppy versions of Simon the Sorcerer), or if the game was ever sold with the copy protection removed and we can't tell from the data files if it's a protected or unprotected version (e.g. the VGA floppy version of The Secret of Monkey Island).
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md5
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Post by md5 »

The copy protection was originally disabled for Indy3 (EGA) and Monkey Island 1 (EGA) in the distant past, due to the copy protection screen not been displayed correctly at the time. But the copy protection was not enabled again, when the graphics display was fixed, until more recently.

We only disable the copy protection, if there is an original release of a game, where the copy protection disabled in code (Not game scripts).

The best way to check, is to see if copy protection codes are included in manuals, although they might often be missing with second hand games. Or run the original game on Amiga/DOS/Macintosh and check if the copy protection is requested.

If you know of any original releases of these games, which had copy protection disabled please add a bug report about the issue. We need to know the exact release of the game, for future reference. It would be useful if the original executable file could be attached to bug report too, so we could examine how original code disabled the copy protection.
http://forums.scummvm.org/viewtopic.php?t=2542
http://forums.scummvm.org/viewtopic.php?t=2586

This has been done with revisions #23502, #23503, about 7 months ago

There is no known version of indy 3 ega or monkey 1 ega that had its copy protection screen disabled, hence you get the copy protection screen.

The protection screen for Ween was never bypassed in any revision afaik
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WNivek
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Post by WNivek »

md5 wrote:The protection screen for Ween was never bypassed in any revision afaik
Actually the US version published by Sierra - under the name The Prophecy (no Ween in the title)- had no copy protection. I don't know if that change was enacted in the executable or the data files, but current builds of ScummVM run the game correctly - no copy protection.
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MusicallyInspired
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Post by MusicallyInspired »

That's fine that ScummVM tries not to bypass copy protection. But what I want to know is why did it bypass before and not now? (And before this all changed I was able to bypass Ween's copy protection screen somehow by entering random numbers)
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eriktorbjorn
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Post by eriktorbjorn »

MusicallyInspired wrote:That's fine that ScummVM tries not to bypass copy protection. But what I want to know is why did it bypass before and not now? (And before this all changed I was able to bypass Ween's copy protection screen somehow by entering random numbers)
The copy protection is often part of the game scripts, so they can be affected by bugs or unimplemented opcodes in ScummVM.
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