Question How to access NativeArray by index when using ScheduleParallel

Hi,

I'm running through a Udemy course on ECS that's quite out of date, so am trying to update the code to run in 0.51.0-preview.32. I have a NativeArray that contains 4 float3 waypoints. If I run the job using .Schedule() it works, but runs at 8fps for 1000 GameObjects. If I try to use .ScheduleParallel() it doesn't work and throws this exception:

Code (CSharp):

1. IndexOutOfRangeException: Index 0 is out of restricted IJobParallelFor range [0...-1] in ReadWriteBuffer.

I believe this is due to the NativeArray being broken into chunks but don't understand how to fix it. Can anyone shed any light on how to make the code bloew work when using ScheduleParallel() please? It's line 8 that throws the error, tankData.currentWP holds a value between 0 & 3, and waypointPositions has 4 items stored in it.

Code (CSharp):

1. protected override void OnUpdate()
2.     {
3.         float deltaTime = Time.DeltaTime;
4.         NativeArray<float3> waypointPositions = new NativeArray<float3>(GameDataManager.instance.wps, Allocator.TempJob);
5.         var dep = Entities.WithName("MoveSystem").ForEach((ref Translation position, ref Rotation rotation, ref TankData tankData) =>
6.         {
7.            
8.             float3 currPos = waypointPositions[tankData.currentWP];
9.             float3 heading = currPos - position.Value;
10.             heading.y = 0;
11.             quaternion targetDirection = quaternion.LookRotation(heading, math.up());
12.             rotation.Value = math.slerp(rotation.Value, targetDirection, deltaTime * tankData.rotationSpeed);
13.             position.Value += deltaTime * tankData.speed * math.forward(rotation.Value);
14.             if (math.distance(position.Value, waypointPositions[tankData.currentWP]) < 1)
15.             {
16.                 tankData.currentWP++;
17.                 if (tankData.currentWP >= waypointPositions.Length)
18.                 {
19.                     tankData.currentWP = 0;
20.                 }
21.             }
22.  
23.         }).WithDisposeOnCompletion(waypointPositions).ScheduleParallel(Dependency);
24.         this.Dependency = dep;
25.        
26.     }

 

Thanks, that's got it working (still something wrong as it's still only managing 8fps but that's probably just some dodgy code somewhere).

I didn't think the Dependecy stuff was required but i'd been trying to piece the solution together from multiple sources, so ended up with a bit of frankencode.

M

 

How did you get it working?