Resident Evil is the game that properly kickstarted the survival-horror genre and made it popular amongst video game players. Capcom's timeless classic was originally released in 1996 for the PlayStation, and was later given a remake that released for the Nintendo GameCube in 2002.
Ever since, Capcom has re-released the game for numerous consoles, and these days players can find Resident Evil HD Remaster — which is a remaster of the 2002 remake — on pretty much any platform out there, which is a testament to its superb quality.
Just recently, YouTube user Harry101UK has been replaying Resident Evil HD Remaster and decided to start meddling with a "global illumination" shader. What's interesting is that he found that the developers at Capcom had actually put a lot more details into the game than any of us had thought.
Resident Evil games — at the time the 2002 remake was released, at least — had all used pre-renderd backgrounds in 2D, which is what gave the games that very realistic look; everything else that wasn't background were actual 3D models, such as characters, some items, and some other objects players could interact with.
Enabling that "global illumination" shader revealed that the Resident Evil remake actually features 3D backgrounds, which wasn't really a known fact. More interesting is the fact that these 3D models are insanely detailed, and most of those details are barely even noticeable.
The shader's debug mode allows us to see what the game looks like without textures, and this is where things get interesting, as it reveals that little details like rocks, candles, syringes, and a bunch of other elements, but that can easily be missed while playing the game.
While it is unclear whether the game uses actual 3D models or "fancy depth maps", these are revealed to be dynamic, and that they also react to moving characters and light, which is also a detail that can be easily missed — but that's the beauty of it; the developers did such a great job that all of these little details enrich the environment without standing out too much that it becomes distracting.
Take a look: