TrollVM is an interpreter that enables the users of modern high-end computers to play arcane low-end Sierra On-Line games with slightly improved graphics and sound using a mouse as an input device.
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| Mickey's Space Adventure (1986) | Winnie the Pooh in the Hundred Acre Wood (1985) |
Game downloads courtesy of Al Lowe's Humor site!
The latest version (2004-01-23):
http://prdownloads.sourceforge.net/trollvm/TrollVM_0.2_Win32.zip?download
Source code (released under GNU General Public License):
http://prdownloads.sourceforge.net/trollvm/TrollVM_0.2_Source.zip?download
How does it work?
TrollVM interprets the data files of the two currently supported games and enables an enhanced game experience by interfacing with modern software and hardware with a free programming library called SDL.
How about some technobabble?
Both games feature enhanced PCjr 16-color graphics. Animation is supported in Mickey. Mickey has PC speaker sound emulated thru the computer's sound card. Winnie has no sound due to a very strange sound file format (help, anybody?). The games can be completed without touching the keyboard once. The mouse can be used to make all verb/noun selections, and also yes/no/press any key selections. Naturally the keyboard will work too.
Can I save my game progress?
Yes.
The Winnie VM uses a similar save game file format as the PC version does, so save games are interchangeable. The original Mickey game unfortunately uses a custom disk format to save games, so interchangeability cannot be achieved. A completely different, file-based format is used to save the games by the Mickey VM.
How good is it?
Mickey works 100% if you don't count some minor faults in the picture fill/plot routines, but Winnie is missing both sound and Tiger/Mist events (I couldn't figure them out from x86 assembly).
How did you do it?
Both game drivers have been programmed based on a disassembly of the original DOS exes, so they are guaranteed to be as similar to the originals as possible. (Without the original source code they won't get any better than that)
File formats were reverse engineered using the best hex editor ever, WinHex. DOS disassemblies conveniently provided by W32Dasm. Programmed with Microsoft Visual C++ 2003.
Check out Mega-Tokyo's AGI/SCI Forum for information on Sierra interpreters!