How GOG.com Save and Restore Classic Videogames

Rock, Paper, Shotgun's Tom Bennet has talked with the people over at GOG.com about the process they use to get old, often abandoned, classics to their digital platform. While the focus has changed over the years, the portal started as Good Old Games for a reason, and just recently saw the addition of classics like the Gold Box games to its catalog. A snippet:

Games generally take one of three paths to the GOG storefront. Newer titles are procured by the company's Business Development team, while small indie releases are often submitted directly by their development studios (Lords of Xulima and Sunless Sea being two such examples). The vast majority of older titles, however, take the third path; whether they've climbed the Community Wishlist or are simply a favourite of GOG's developers, their distribution rights must be hunted down manually. To that end, the legal team scrutinise the storied history of the game's original development studio, connecting the dots between mergers, buyouts, and bankruptcies, searching for clues as to which publisher or conglomerate to contact.

(On more than one occasion, our community was also extremely helpful in tracking down classic games,) says Paczyński. (A GOGer might know somebody involved with a release, or try a few of their own leads and share anything that they come up with. There's actually a community thread on our forums dedicated specifically to this sort of thing, and in the past we've been able to follow up on these leads to release the games they requested. It's always awesome to add a game to GOG.com that's the product of a combined effort between our team and our community.)

Once a deal has been struck with the new rights holders, the team are in theory free to update the game's ancient source code to run on modern systems. There's one problem, however: in almost all cases, the original code has been lost or deleted.

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Retail code is far less malleable than source code, and restoring a game to its playable state using only a decades-old installation disk is quite a feat of software engineering. In terms of sheer difficulty, the process might be likened to film restoration using only a VHS recording of a television broadcast, the original negatives having been destroyed.

GOG's engineers must therefore take a creative approach by using customised emulators and wrappers. (We have a great relationship with the team behind DOSBox,) explains PaczyÅ„ski. (In the past they've helped us create custom setups specifically for a particular release notable examples include Theme Park and Harvester.) It's not uncommon for these setups to become extraordinarily complex; the team describe wrapping wrappers around wrappers in a kind of '˜Russian Doll' approach to emulation.