Burst Occlusion is in broken state

[Rukhanka]

I am experimenting with burst occlusion feature, but it is not working from the box. The simplest freshly created HDRP project with a trivial setup (one occluder, one occludee) spits out error messages to the console:

IndexOutOfRangeException: Index 1 is out of restricted IJobParallelFor range [0…0] in ReadWriteBuffer.
ReadWriteBuffers are restricted to only read & write the element at the job index. You can use double buffering strategies to avoid race conditions due to reading & writing in parallel to the same elements from a job.

Unity.Collections.NativeArray1[T].FailOutOfRangeError (System.Int32 index) (at <e17944dc3c824e30af7da0a4ebe81ca3>:0) Unity.Rendering.Occlusion.Masked.Dots.OcclusionMesh.Transform (Unity.Mathematics.float4x4 mvp, UnityEngine.Rendering.BatchCullingProjectionType projectionType, System.Single nearClip, Unity.Burst.Intrinsics.v128* frustumPlanes, System.Single halfWidth, System.Single halfHeight, System.Single pixelCenterX, System.Single pixelCenterY, Unity.Mathematics.float4* transformedVerts, Unity.Collections.NativeArray1[T] clippedVerts, Unity.Collections.NativeArray1[T] clippedTriExtents, Unity.Rendering.Occlusion.Masked.ClippedOccluder* clipped) (at ./Library/PackageCache/com.unity.entities.graphics@1.0.8/Unity.Entities.Graphics/Occlusion/Masked/Dots/OccluderMesh.cs:274) Unity.Rendering.Occlusion.Masked.MeshTransformJob.Execute (System.Int32 i) (at ./Library/PackageCache/com.unity.entities.graphics@1.0.8/Unity.Entities.Graphics/Occlusion/Masked/MeshTransformJob.cs:55) Unity.Jobs.IJobForExtensions+ForJobStruct1[T].Execute (T& jobData, System.IntPtr additionalPtr, System.IntPtr bufferRangePatchData, Unity.Jobs.LowLevel.Unsafe.JobRanges& ranges, System.Int32 jobIndex) (at :0)

There is no source code for the NativeArray class, so I cannot understand the source of this issue. But I have replaced NativeArray with NativeList in the corresponding EntitesGraphics source files, and everything become fixed.

[IsaacsUnity]

Hey Rukhanka, thanks for flagging this. Please note that Burst Occlusion Culling is an experimental feature and we do not support it for production. That said, our teams are aware of this and are sifting through a plan to resolve related Burst Occlusion Culling bugs and issues. We’ll share back when there’s progress!

Side note: Congrats on the amazing ECS animation package, it’s great stuff!!

[Rukhanka]

@IsaacsUnity

Hey Rukhanka, thanks for flagging this. Please note that Burst Occlusion Culling is an experimental feature and we do not support it for production. That said, our teams are aware of this and are sifting through a plan to resolve related Burst Occlusion Culling bugs and issues. We’ll share back when there’s progress!

Thank you for the information.

Side note: Congrats on the amazing ECS animation package, it’s great stuff!!

Oh. Thank you very much

[Yury-Habets]

@Rukhanka here is an issue which may be related: https://issuetracker.unity3d.com/issues/burst-occlusion-culling-errors-spam-editor-console-when-burst-is-disabled

We’re investigating if it’s the same issue or not.

[Rukhanka]

@Yury-Habets

@Rukhanka here is an issue which may be related: https://issuetracker.unity3d.com/issues/burst-occlusion-culling-errors-spam-editor-console-when-burst-is-disabled

We’re investigating if it’s the same issue or not.

Thank you for the information. I have an exception spamming with and without burst enabled state. Changing clippedVerts and clippedTriExtents arrays types from NativeArray to NativeList in UnityOcclusion.cs (and corresponding further job definitions) removes any exceptions and put burst occlusion feature in working state.