It would be interesting to hear your experience in developing for RTX for those of us who know nothing about how that side of the business works. We just enjoy the pretty pictures...
What challenges are you faced with?
How is it different from the technology you currently implement?
Does the RTX tech provide you with variable levels of raytracing to balance the performance / quality or is it all or nothing? Meaning can you control the amount of time that is raytraced to maintain the real-time aspect of Enscape but also use more time when saving out the image for a final render?
Anything else you want to share?
already gave quite a good overview on the topic in his answer.
Here're some of the details I can share which you've asked:
One of the main challanges up to now was that we've got our existing rendering engine implemented completely based on the graphics API OpenGL. However Nvidia's RTX technology is only available for the recently introduced APIs DirectX12 and Vulkan, which differ greatly in the way they work compared to DirectX11 or OpenGL. To my knowledge we're one of the first/few developers that now have Vulkan RTX working in interoperability with an OpenGL engine.
The main difference is "just" how the ray intersection with your scene geometry is calculated, which is required for lighting calculations in a path tracing algorithm. But since this operation is the most expensive one when it comes to path tracing, ray intersections with hardware acceleration allows quite some speedup compared to previous implementations in software. It's basically the same step as when you still had real-time rasterization of 3d graphics done in software back in the 90s up until gpus were introduced with dedicated hardware for that.
RTX is just a tool to do ray-geometry intersections. What performance or quality get, is completely up to how the developer implements the rendering algorithm. As TowerPower
mentioned: We've already implemented a real-time capable path tracing algorithm - RTX won't change that much in the way an image is rendered with Enscape. But it will allow users with RTX hardware to benefit from a significant speed-up of indirect light computations. The result beeing that you'll have better frames per second in a scene with the same geometric complexity, or get similar performance you currently have, but in much larger or more detailed scenes.
So it's unlikely that the feature set of Enscape will differ much (if at all) for users with RTX to non-RTX users - you'll definitely still be able to render the same image quality with very competetive speed using Enscape without RTX hardware in the future.