This post is for the long time followers of this blog: one year ago, I've created a real-time path traced racing/physics game called "Unbiased Stunt Racer" (see
http://raytracey.blogspot.co.nz/2011/09/unbiased-stunt-racer-in-hd.html). The game could run in real-time with path tracing because it only used spheres and boxes as primitives (about 50 primitives in total). Here's a screenshot:
Now, one year later, we can path trace dynamic scenes containing millions of triangles in real-time with Brigade, so the progress we made was not that bad. As a proof-of-concept, we've created a small racing game featuring a tiny race car, complete with physics. Thanks to some further optimizations, Brigade is now rapidly approaching a point where it can instantaneously render noise-free photorealistic images. The video below isn't even using the latest code (which has massively improved support for dynamic scenes) yet. The photorealism you can get out of Brigade nowadays is unrivaled and unique in the world of game engines. The potential of this tech is endless: for example, the automotive industry can render a photoreal and interactive car commercial in real-time or allow their customers to virtually drive around in a photoreal 3D city with the car of their dreams reflected in the display windows...