If you want to see the potential of ray tracing, you should look to Quake 2. A new mod called Q2VKPT (Quake 2 with Vulkan path-tracing) is out now that adds real-time ray tracing to the classic shooter. And while Nvidia has turned to cutting-edge releases to hype people up for RTX, maybe it should use Quake 2 instead.

In the 3-minute video above, you can see how effective RTX is at bringing a scene to life. White wall lamps reflect off of the floors. Explosions bathe the environment in momentary bursts of orange. And water reflects the entire room around it.

All of this next-gen lighting tech is happening in a game that is from 1997. But RTX gives the world a sense of place and reality that looks almost modern. Sure, the enemy models are blocky and under animated, but they look like they are moving through physical space.

Why Q2VKPT looks so good

The demo’s realism is due to light behaving in a way that is consistent with our real-world experience. That’s something that I didn’t even realize was missing from games until now. If a red barrel exploded in a video game for the last 30 years, it would never give off that blinding flash that you get from ray tracing.

Ray tracing is here now, and it’s only in one game, sort of. Battlefield V uses a hybrid of RTX and traditional methods for its lighting effects. Q2VKPT, meanwhile, uses everything.

“The recent release of GPUs with raytracing capabilities has opened up entirely new possibilities for the future of game graphics, yet making good use of ray tracing is nontrivial,” computer graphics Ph.D. candidate Christoph Schied wrote in a blog post. “While some games have started to explore improvements in shadow and reflection rendering, Q2VKPT is the first project to implement an efficient unified solution for all types of light transport.”

Q2VKPT uses ray tracing for direct lighting, light scattering, and reflections. These are methods that the movie industry has used to improve the quality and speed of their visual effects.

“The chance to have the same development in games promises a similar increase in visual fidelity and realism for game graphics in the coming years,” reads Schied’s blog.

Put ray tracing in indie games now

The Quake 2 demo proves that ray tracing works well in less detailed 3D games. And that means it’s something that today’s indie-game developers could start putting into their games.

The problem with that is that ray-tracing tech is still hardware intensive and only a handful of cards work with it. So a small studio can’t just flip a switch to add RTX lighting to their game and then ship it. Indie teams would have to build a lighting model and then add RTX as well.

But Q2VKPT proves that it’s not only possible — it also produces stunning results.