Given the somewhat stalled rate at which consumer real-time imagery has been evolving the past half-decade or so, it’s hard to imagine now that there was a period of time when one could basically pinpoint a game to a specific year of release by the mere looks of it. Consider, for instance, the consequential jumps in visuals from Wolfenstein 3D (1992) to Doom (1993), and further on to Descent (1994) – all this in a span of 31 months.
For reasons beyond me, Quake released in 1996 is often attributed as the first commercial engine that popularized the full 3D paradigm in a first-person context even though it was Descent that did the same exact thing 18 months prior. Sure, the Quake Engine was undeniably more sophisticated in a number of respects, but Descent was de facto trailblazer of that short period of time between so-called 2,5D (aka pseudo-3D) such as Doom and full 3D such as Quake.
On a side note (and in all fairness), the Ultima Underworld games released in 1992 and 1993 did were very closely in par with Descent judging solely by the list of supported features. However, the UU graphics engine was simply so far ahead of its time that a) there wasn’t hardware available that ran it at aesthetically pleasing speed, and b) the engine itself was a bit of a mess and far from the robustness of the aforementioned games, such as Descent. Therefore, I feel the UU engine was a bit “cheating” its way to the avant-garde position it held a couple of years.
So, not only Descent expanded the simulation of (texture-mapped) space into six degrees of freedom and introduced actual 3D enemies instead of sprites to the first-person genre, Descent employed a dynamic lighting system that was rather mind-boggling at the time. In contrast to Doom and the like, in addition to the static lighting Descent allowed traversing light sources that rendered shooting lasers and missiles quite a spectacle, especially in narrow corridors which Descent was known for.
It was indeed the shadowy tunnels that really showcased the dynamic lighting in action, and I remember reading at least one review of Descent at the time raving about how impressive the setting in question was. Furthermore, I’m pretty sure the exceptionally dark and lenghty tunnels found here and there in Descent were included into the level design precisely to bring forward the then-novel lighting system, and as such, successfully so.
Sometimes there is a distinct moment when a new technology establishes itself and becomes an actual, tangible reality in one’s mind. For me, that dark tunnel in Descent that lighted up as the missile glided through was one of those defining moments, and even if the effect was rudimentary at best, it was a substantial step towards dynamic illumination in a real-time context at large. Light sources simply couldn’t be completely fixed anymore from then on.
As said, 18 months later Quake did ended up pushing both static and dynamic lighting forward making Descent visually obsolete. Funnily enough, it was this time around the static lighting that impressed me the most, particularly the unprecedented, if static, cast shadows in the environments. Interestingly it took in turn almost a decade to make such shadows move and react in real-time.
For me, following and contemplating real-time imagery, and technology in general, is all about moments of realization that something that wasn’t considered feasible is now just that. And it can be a darkest tunnel that shines light on that new reality.