Fast and Fun: My First Real-Time Ray Tracing Demo

Originally published at:

Editor’s note: What happens when a veteran graphics programmer with substantial experience in old-school ray tracing (in other words, offline rendering), gets hold of hardware capable of real-time ray tracing? I’m finally convinced. I joined NVIDIA around SIGGRAPH, just as the RTX hardware for ray tracing was announced. I saw the demos, heard the stats, but…

Builds ok but issues running with Windows 10 October Update (v 1809), which is the first formal release with DXR supported.

It does not work on RS5 yet. No ETA on when it’ll be ready. (I'm quoting Chris Wyman here)

No demo code?

Available here:

Looks awesome!
I would love to see a recorded video of the demo :o

Obviously won't be able to do realtime but can I do rendering without an RTX card? If not, can someone dig deep into their pockets and get me one lol.

Also, the download for the MDL SDK appears to be broken. Seemingly no extension is provided or no mime and I am to paranoid to rename the extension in an attempt to extract it.

Oh, I see, you're talking about this other blog post, - the demo code here doesn't use the MDL SDK, you don't need it. I think these demos *could* run on other cards, but haven't tried myself - let me know what you find. I suspect we'll need to update them to the Windows 1809 update (currently pulled by Microsoft due to a file deletion problem).

For the MDL SDK, you could directly download it from I'll ask others at NVIDIA to fix the direct download link on the giving the file "mdl-sdk-307800.2890.solitairetheme8" - thanks for letting us know!

we need real time generative cfd for unreal! Incredible study! thanks for sharing.

I am having a hard time getting started using Visual Studio 2019. Is there an issue here with the incompatibility of VS2017 build tools and those of VS2019?
How should I proceed?
Thanks in advance for any help.