Old IJobParallelFor Script doesn't work on Unity 2019.3.4

Hello guys,
I have ported my old gravitation script to a new project.
I just want to pass two readonly arrays to a job. This worked in Unity 2019.2, but ported to Unity 2019.03.4 I get this error: Assets\Systems\ForEachGrav.cs(14,12): error CS0453: The type 'ForceData' must be a non-nullable value type in order to use it as parameter 'T0' in the generic type or method 'IJobForEach_CCC'
What does that mean?
I know UNity changed the Syntax [Readonly] to in, but changing this also didn't worked out.

Code (CSharp):

1.       using Unity.Burst;
2.          using Unity.Collections;
3.          using Unity.Entities;
4.          using Unity.Jobs;
5.     using Unity.Mathematics;
6.     using Unity.Transforms;
7.     using UnityEngine;
8.     public class ForEachGrav : JobComponentSystem
9.     {
10.          struct ForEachGravJob : IJobForEach<ForceData, MyMassData, Translation>
11.          {
12.              [DeallocateOnJobCompletion] [ReadOnly] public NativeArray<MyMassData> masses;
13.              [DeallocateOnJobCompletion] [ReadOnly] public NativeArray<Translation> translations;
14.              public void Execute( ref ForceData f, [ReadOnly] ref MyMassData mass, [ReadOnly] ref Translation t)
15.              {
16.                  float maxVel = 0.5f;
17.                  float3 newForce = new float3(0, 0, 0);
18.                  var mass1 = mass.mass;
19.                  float3 posi1 = t.Value;
20.                  var force1 = f.Value;
21.                  for (int j = 0; j < masses.Length; j++)
22.                  {
23.                      var mass2 = masses[j];
24.                      var posi2 = translations[j];
25.                      float3 p1 = posi1;
26.                      float3 p2 = posi2.Value;
27.                      float d = mass2.mass * mass1 * 6.67f;
28.                      p1 = p2 - p1;
29.                      float magnitude = (math.length(p1));
30.                      if (magnitude != 0 && magnitude > 1f)
31.                      {
32.                          p1 = (p1 / math.pow(magnitude, 3)) * d; //force
33.                          newForce += p1;
34.                      }
35.                      f.Value = newForce;
36.                  }
37.              }
38.          }
39.          private EndSimulationEntityCommandBufferSystem endsim;
40.          protected override JobHandle OnUpdate(JobHandle inputDependencies)
41.          {
42.              EntityQuery q = GetEntityQuery(ComponentType.ReadOnly<MyMassData>(), ComponentType.ReadOnly<Translation>());
43.              NativeArray<MyMassData> masses2 = q.ToComponentDataArray<MyMassData>(Allocator.TempJob);
44.              NativeArray<Translation> poss2 = q.ToComponentDataArray<Translation>(Allocator.TempJob);
45.              (Allocator.TempJob);
46.              var job = new ForEachGravJob
47.              {
48.                  masses = masses2,
49.                  translations = poss2,
50.              };
51.              var handle = job.Schedule(this, inputDependencies);
52.              return handle;
53.          }
54.     }

 

Welcome,

Is your
ForceData : IComponentData?
Does it have properties (none empty) inside?
You still should be able pass it into a job, without [ReadOnly] attribute.

 

Thanks for the quick respons. Yes it is. It holds just a float3.
I tried to just delete the readonly field, still same error :/

 

your IComponentData should be a struct, not class.

 

@Curlyone may have valid point.
@GamerLordMat can you show us part of the code with definition of ForceData, MyMassData components?

 

I really forgot to make it a struct , changing it to a struct worked out. I thank you all a lot.

 

It's struct, not class ICD version?
Edit: Ah already answered, not refreshed the page

 

Thank you everyone for your help, it is a stupid error but I didnt know how to interpret the error code.
Btw, how to close this question know?

 

I think you can just edit the title to mark is as resolved.