I spent hundreds of hours playing LucasArts adventures in the early '90s. The Monkey Island series, The Dig, Full Throttle, Indiana Jones & The Fate of Atlantis, Day of the Tentacle, Sam & Max, Zak McKracken -- all these adventures were written to run on an engine called SCUMM (Script Creation Utility for Maniac Mansion). Open Source developers almost two years ago started ScummVM (SCUMM Virtual Machine), a project to create a SCUMM-compatible engine capable of running those games on today's hardware.
SCUMM is like a virtual machine, while a game is a collection of scripts that create the environment and react to player actions. When a game was to be ported to another platform, LucasArts simply needed to port the engine, reusing the original game scripts, graphics, and sounds. ScummVM acts as simply another platform.
Built on top of SDL, the Simple DirectMedia Layer, a multi-platform multimedia library, ScummVM runs on multiple operating systems. Currently there are versions for Linux (i386 and PowerPC), FreeBSD (it's part of the ports collection), Mac OS X, BeOS, MorphOS, Solaris, IRIX, the Sega Dreamcast, Playstation 2 with the Linux Kit (a native port is in the works), the ultra-cool Korean portable GamePark32 (what about Day of the Tentacle on-the-go?), Windows, WinCE, and many other operating systems and devices. Getting it to run is easy; the download page on the official Web site has precompiled binaries for many of the supported platforms, and you can always get the source code and compile it yourself.
ScummVM is just the engine; you need the original CD or floppies with the game datafiles -- graphics, sounds, and scripts. To play, launch ScummVM, and on the management interface (which is very similar to the one used on LucasArts games) click on Add Game. Point to where the original datafiles are, specify whether you want the game to run full screen, in a window (you can toggle between the two modes in-game by pressing Alt+Enter) or use the Amiga palette (so the colors on Amiga versions of those games look right) and click Start. Then play the game as you would on your old 486 with a 14-inch VGA monitor and DOS 6.
You don't need to have the game CD or floppies in the drive every time you want to play. You can copy the datafiles to your hard drive and run from there. This is useful if you can't use your floppies anymore (for example, if they are Amiga disks, or if you have a Mac) or want to save your original CD from the wear and tear of everyday use. What if the game uses CD Audio? No problem -- you can compress the game soundtrack as MP3 or Ogg Vorbis files and use them that way if you compile ScummVM with MAD (or libvorbis) support. Other nice touches include extra graphic modes, like 2x or 3x zoom; filtered modes, like 2xSaI, Super 2xSaI, SuperEagle, AdvMAME2x; and even TV emulation, all of which can be specified as command-line options. Auto save is also present as a precaution against unexpected crashes (though I've never had one, but it could happen). The current game is saved every 5 minutes on slot 0. However, there's no support for your old save games. In fact, there's no support for save games created with older versions of the engine, as the format has changed. The FAQ warns that this may happen again in the future.
You're not limited to LucasArts adventures. Games by Humongous Entertainment (Putt-Putt Joins the Parade and Putt-Putt Goes to the Moon), Adventuresoft (Simon the Sorcerer 1 and 2), and Revolution Software (Beneath a Steel Sky and Broken Sword II) are also supported. Not every game is fully playable; there's a compatibility list on the project's home page, but many games are already up to 95%, which means "fully completable with minor glitches."
I still have the CDs for two adventures, Full Throttle and The Dig. While support for Full Throttle is still preliminary, The Dig is one of those at 95%. The game runs almost flawlessly -- I only noticed the occasional minor sound glitch, nothing to worry about. Performance was also good, both on my 1.3 GHz AMD Duron PC running Red Hat 9 and on my trusty old Rev. B iMac with a PowerPC processor at 233 MHz running OS X 10.2.8. And even if you don't own any old adventures anymore, you can still have some fun with ScummVM: Revolution Software Ltd., maker of the adventure Beneath a Steel Sky, originally released on DOS and Amiga versions, not only donated the original source code for the game (so it can be quickly added to the supported list without lenghty reverse-engineering), but allowed the game itself to be released as freeware. You can download a complete copy of Beneath a Steel Sky, both floppy disk and CD versions (with voice, about 70MB) from ScummVM's Web site. Hurray for Revolution Software, and for ScummVM!
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