Using the DirectX Raytracing API in Unity

I'm trying to find examples / info on how to build custom shaders using the DirectX Raytracing API in unity.

This presentation:

(slides) https://on-demand.gputechconf.com/siggraph/2019/pdf/sig940-getting-started-with-directx-ray-tracing-in-unity.pdf

(video) https://developer.nvidia.com/siggraph/2019/video/sig940-vid

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shows exactly what I want to accomplish : use the DirectX API to handle my custom raytracing methods. However, there are not enough details, and it seems like it may be a little out of data now based on the documentation that is available in Unity:

https://docs.unity3d.com/ScriptReference/Experimental.Rendering.RayTracingAccelerationStructure.html

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So, here's where my understanding is, and please correct me if I'm wrong (I probably am)!

1)

I need to write a Ray Generation shader by creating a .raytrace shader. This is easy ( I think ). It can be dispatched like a compute shader from the c# side in Unity.

2)

Because the direction of my rays will change continuously as it moves through space searching for an intersection, I need to take more of a ray marching approach with a small step size. So, from the Ray Generation shader, I will call TraceRay() function from the DirectX API on the initially created ray with a small tMax parameter.

3)

Since I am ray marching to find an intersection, and updating the direction of the ray at each step, I need to spawn a new ray on every miss - so I need a custom Miss shader that accompanies my Ray Generation shader (same file?). The miss shader will calculate the new ray direction and origin and call TraceRay() again. So this is a recursive process, and the Miss shader will be calculated MANY times until some max distance traveled by the ray has been reached or until we encounter a hit!

4)

In order to tests for a hit, I need an Intersection shader. Since I will be using meshes in my scene - with mesh renderers, I believe Unity will automatically manage the Acceleration Structure by adding the game objects with a mesh renderer to the structure in order to be tested for intersection. And so I don't think I need to make my own custom intersection shader or manually manage the Acceleration structure. But I'm confused on how exactly I use the RayTracingAccelerationStructure in Unity - the documentation is not clear to me. Can someone clear this up?

5)

When an intersection is encountered, a Hit shader will be called (I don't need to worry about AnyHit shaders I don't think, so we'll ignore those for now). Basically, I just want this shader to return the mesh texture at the intersected UV coordinate. I believe for this I just need to add a Hit shader that does this as a sub shader in the mesh's material, right?

6)

From there I can graphics.Blit the texture that the raytracing writes to (?)

I would really like to see a full unity example that implements these steps like I've laid out. It would be really helpful! Also, if I am misunderstanding something, please let me know.

Thanks.