Working on Monkey Island Special Edition in 2009 while at LucasArts is one of the highlights of my career. I have really fond memories of my time there on the team (Team 3!). I wish I had worked on the original but that was way before my time.
The game is actually running the full original code alongside the new Special Edition stuff. We didn’t want to disturb the original codebase, so we ran it basically unchanged on another thread and the new game loop would surgically peek and poke some state every frame (animations, etc) to get synchronized. That’s how we essentially layered all the new art and sound on top of the original game. There was a lot of reverse engineering of data and asset formats that we had to do because all the original authors had since left, perhaps with the exception of EJ.
The F10 hotkey to transition between the old and the new art was actually a debugging feature that our lead rendering engineer wrote during development, but everyone agreed that it was too good not to ship it as an actual feature of the Special Edition.
For those who didn't experience it the first time or perhaps would like to do so again, I feel obligated to mention your version is on sale for $3.49 at Good Old Games aka gog.com. No affiliation myself other than a customer and someone a bit in awe of what you guys wrought.
The game is actually running the full original code alongside the new Special Edition stuff. We didn’t want to disturb the original codebase, so we ran it basically unchanged on another thread and the new game loop would surgically peek and poke some state every frame (animations, etc) to get synchronized. That’s how we essentially layered all the new art and sound on top of the original game. There was a lot of reverse engineering of data and asset formats that we had to do because all the original authors had since left, perhaps with the exception of EJ.
The F10 hotkey to transition between the old and the new art was actually a debugging feature that our lead rendering engineer wrote during development, but everyone agreed that it was too good not to ship it as an actual feature of the Special Edition.