fitting RaycastCommand into a job chain

So I have a job chain where I'm working with sparse data. But I'm having challenges figuring out how to fit raycasting into that.

So my scenario I have a job that calculates some data for projectiles, then a dependent job moves the transforms based on that same data. The data is basically sparse as it's complex enough where without some smart partitioning I either end up allocating constantly or iterating over tons of items I don't need to work on. So I have a partitioning system where work is filled into partitions sequentially, so worst case there is one partition not fully assigned that I have to iterate over.

The challenge is I need to create new NativeArray's here for raycasting, since I'm working with sparse data and the size changes every cycle. But I can't see a way to do that. I can only allocate a NativeArray in a job in the scope of Execute. So the option of allocating at the job scope and then disposing where I Complete won't work. It looks like I can pass a JobHandle to a job, so I could use that to kick off the raycasting. But that complains about being unsafe, so I'd rather find another route if possible.

 

So the docs on this almost imply that RaycastCommand is meant to be used inside a job? I didn't try that just because it wasn't really clear.

 

Ok well as recent as B8 it appears it ignore dependencies anyways, so that makes this easy for now.

 

So what I ended up doing is just caching NativeArray's by size, since I have partitions I'm guaranteed the max number of arrays is partition size.

 

Ah ok nice I can ditch my pre allocating a NativeArray for every unique size. Thanks for the info.

 

Even if the generating job handle is passed into RaycastCommand.ScheduleBatched as a dependency, the RaycastCommand.ScheduleBatch call throws an exception.

Code (csharp):

1.  
2.             PrepareRaycastJob prepareJob = new PrepareRaycastJob(commands, distance, layers, commandCount);
3.             JobHandle prepareHandle = prepareJob.Schedule(transformAccess);
4.  
5.             jobHandle = RaycastCommand.ScheduleBatch(commands, hits, Mathf.Min(commandCount, 10), prepareHandle);
6.  
7.  
8. InvalidOperationException: The previously scheduled job LegContactManager:PrepareRaycastJob writes to the NativeArray PrepareRaycastJob.commands. You must call JobHandle.Complete() on the job LegContactManager:PrepareRaycastJob, before you can write to the NativeArray safely.
9.  

 

That looks like a really useful error message. Great job people of Unity Technologies!

 

Very related. Check my blog post on this:

How to use the results of raycastCommand.ScheduleBatch in another job.

Hope this helps somebody who's looking for a little help. I have other jobs and efficiency related posts there.