Bug DXR Bugs -- Generally and for manual RTAS code

Currently for: 2023.1.0b14 but these things were seen with at least b13/12/11 as well

This is my first forum post
..not sure whether I should create a bug report for each of those but I'll just summarize them all here

All materials used in testing are using the "HDRP/Lit" shader

1.
For the "Ray Tracing Settings" override whether I am using "CullInstances()" with "Manual" or instead directly use "Automatic" I am not seeing shadows for the existing gameObjects of the scene

2.
There seems to be an unintentional fallback mode for at least SSAO when having the "Ray Tracing" checkbox disabled and then further disabling the volume override
..or it's the other way around and fallbacks instead are missing for other things like SSGI, SSR and especially SSS
=> Right now objects not within the RTAS don't cast shadows at all and a fallback for that would be nice for mixed use cases which I do have

3.
Which leads to the next point
=> Objects not within the RTAS (rendered with "RenderMeshXXX" functions, which thus don't have any (fallback) shadows) are still affected by (fallback?) SSAO and SSGI

4.
Having the "Ray Tracing Settings" override enabled and then toggling the "Path Tracing" override can cause a massive constant FPS drop while it's disabled
..entering/leaving play mode fixes/resets this behavior respectively
This is easily reproducable but doesn't always happen
..this could further be amplified by having underlying manual RTAS camera assigments that run for both the edit and play mode but I have no accurate data on that as it happens for both cases(not running the assignments at all) either way

Next up some points about using "manual" RTAS, also together with "AddInstances()"

1.
Objects added through "AddInstances" only work with the "Path Tracing" override enabled
=> else they only exclusively show up in either pure reflections or via indirect shadowy artifacts
Further issues could exist but aren't testable as the objects don't directly show up afterall anyway
.."Path Tracing" itself seems to work fine generally


2.
The "RayTracingMeshInstanceConfig" has a broken or undefined default constructor
This here works
rtInstanceConfig = new(null, 0, null);
rtInstanceConfig.mesh = mesh;

This here does not work
rtInstanceConfig = new();
rtInstanceConfig.mesh = mesh;

I want to use a single global variable and not need to re-create the struct per frame => for loop rotation which is the current workaround with the null passes

3.
For both "RayTracingInstanceCullingConfig" and "RayTracingMeshInstanceConfig" the "subMeshFlagsConfig" and "subMeshFlags" respectively have a potential issue with "RayTracingSubMeshFlags.ClosestHitOnly"
=> Using this flag with ex: "tree leaves" that use alpha clipping it does work like expected, however the shader still gets correctly applied in reflections of the tree thus alpha clipping is being applied in reflections which it shouldn't I'd expect since the direct representation of course doesn't apply alpha clipping
..so if that is unintentional the flag should probably be checked on not only for reflections but where ever else it is(should be) used in

 

Please create a bug report! If you look throughout the forums the devs always say to do it. You can always post the IN number once you get it.

 

Could you perhaps comment on any of the OP fascinating findings/questions please @INedelcu ?