The transformative power of ray tracing has proven itself in many different games, but perhaps the most impressive upgrades have come from revisiting older, classic PC titles, and a recent mod for the original Quake yields nothing short of astonishing results. This is less of a mod and more of a full RT remaster for one of the best PC games, courtesy of Sultim Tsyrendashiev, creator of path-traced renditions of Serious Sam and Doom, and currently working on RT Half-Life. Tsyrendashiev has taken the Vulkan port of Quake by id Software’s Axel Gneiting and delivered something very, very special.
But first, how do you get your hands on the custom game? Just download the necessary files from the VKQuake-RT github page and merge them with the version of Quake you own following the instructions on the page. It’s all relatively easy, but I recommend making a small change to the instructions. DLSS and FSR2 are supported – and both generally give great results – but the recommended DLSS 2.4.0 should be replaced by the earlier DLSS 2.2.6. Doing this eliminates blurring issues that occur with the more recent rendering of Nvidia’s machine learning upscaling technology.
In addition to image reconstruction, gamers actually get two different RT implementations with this mod – a ‘classic’ option that looks more like the original game with some very nice ray-traced upgrades, alongside a full path tracer, which radically changes the game’s aesthetic. transforms .
The classic renderer uses ray tracing for all primary rendering of geometry, but the lighting is still handled through texture-based lighting maps like the original game, meaning you get similar lighting and atmosphere, with some intriguing RT effects: water surfaces are completely different, with RT reflections showing the entire environment. You also get RT-specific underwater image distortion effects. A really nice upgrade comes from the teleporters, which now show you the area you arrive at as you travel through it, Portal style.
The path-traced option offers a more radical transformation by using path-tracing for all of the game’s lighting, completely replacing light maps, and the other tricks Quake used to simulate the appearance of light in 1996. Indoor scenes are illuminated by flares and other small light sources, casting dynamic shadows from suitable objects. As part of this system, all gunfire muzzle flashes also cast light and shadows, leading to some pretty awesome moments in the dark, reminiscent of Doom 3. One of my favorite RT elements is the lightning cannon, which is used throughout time sheds light. the surface of the trace as it leaves the barrel of the weapon.
One of the biggest changes is the use of emissive illumination planes, something that is only possible with RT. Teleporter pads with their little red lights cast light and shadows on nearby surfaces – confirming that colored lighting has also been added, something missing from the original Quake. Of course, lava is also an emissive light source, dramatically transforming many scenes.
More impressively, the sky itself is an emissive light source, so the iconic purple skybox now literally casts purple-hued light on the world below, an incredible effect enhanced by the injection of truncated voxel fog, which can also be illuminated. The voxel grid is a bit coarse so you can see liasing in the volumetric fog, but it looks good enough and if you don’t like it you can turn it off individually in the options menu, revert to a generic distance fog – or no completely fog.
One of the more controversial changes I’d say comes from the alteration of the dangerous chemical pools in the game: in the original they’re green/brown textures, but here they’ve been transformed into a super bright neon teal. Yes, it’s more clearly marked as a hazardous material, but it looks a bit overbearing in some environments, where I imagine a less intense and more muted off-green would suit the mood better.
Other complaints? When the lights suddenly go out, there’s an extended afterimage of the lit scene that gradually fades away, which looks rather awkward. Another problem concerns some surfaces that have a reflective element. The specular lighting updates very slowly, which means muzzle flashes from weapon fire will last for some time. It looks very strange. The final issue is that scenes that lack a lot of direct lighting have a speckled appearance, as the denoiser can only do so much given the low lighting conditions. So there are definitely some issues, but nothing that detracts from the overall quality of the presentation. Ultimately, describing the RT effects is no substitute for seeing them in action, so check out the video embedded above.
In terms of performance, it’s interesting to note that both classic and path-traced renderers have only a margin of error in frame rate (you can switch between them at any time with the press of a button, which may help explain why) and in terms of settings there’s no lots to tweak – so adjusting resolution and by extension using image reconstruction techniques like FSR2 and DLSS2 are the way forward. Moving from native 4K to 4K DLSS quality mode on an RTX 4090 improves performance by nearly 100 percent, with similar near-linear scaling as you move into Performance and Ultra Performance modes. Image reconstruction helps immensely here to the point where an RTX 2060 achieves a locked 1080p60 with GPU space to spare using the DLSS quality mode.
An RTX 3080 will get you to 4K60 locked in DLSS quality mode, but even in FSR2 performance mode, AMD’s RX 6800 XT had some unfortunate frame rate issues. At native resolution, the RTX 3080 offers twice the performance of the RX 6800 XT – not entirely unexpected with a path-traced workload like this – but given the disparity at native resolution, I really would have expected the 4K FSR2 performance mode to deliver 60fps on the more expensive RDNA 2 cards, so I think the AMD side might need some work.
In summary, this traced version of Quake is an incredible way to revisit the game – it’s also fun for newcomers and those interested in RT in general. Simply put, a classic PC title gets a phenomenal upgrade and if you’ve got the means, I highly recommend giving it a go.