Nvidia apparently had a private venue away from the Computex 2015 show floor last week, and it was showing off a new DirectX 12 demo titled Mech Ti. Japanese site 4Gamer captured the six-minute reel and shared the clip with the world:
Ray-traced shadows are on display courtesy of DX12's conservative raster mode. We also see "sparse smoke," an interactive particle effect that appears to take advantage of DX12's volume tiled resources capability.
Thanks to TR tipster SH SOTN for the heads-up.