SPH ECS to unity 2019.2 need help

Hello all, I am trying to implement a fluid system for an application using ECS.

Here is the source code I am trying to convert to unity 2019.2: https://github.com/leonardo-montes/...PH/blob/master/Assets/Job System/SPHSystem.cs

My problem areas:

Code (CSharp):

1.  // Cache the data
2.             NativeArray<Translation> translations = SPHCharacterGroup.CopyFromComponentDataArray<Translation>(null, out inputDeps);
3.             NativeArray<SPHVelocity> velocities = SPHCharacterGroup.CopyFromComponentDataArray<SPHVelocity>(null, out inputDeps);

In the above code I am using the argument null as a placeholder because I can't figure out what to use there, the original (containing deprecated code) looks like this:

Code (CSharp):

1. // Cache the data
2.             ComponentDataArray<Position> positions = SPHCharacterGroup.GetComponentDataArray<Position>();
3.             ComponentDataArray<SPHVelocity> velocities = SPHCharacterGroup.GetComponentDataArray<SPHVelocity>();

And my final errors are here, on particle count:

Code (CSharp):

1.             // Copy the component data to native arrays
2.             ComponentDataFromEntity<Translation> particlesTranslationJob = new ComponentDataFromEntity<Translation>();
3.             JobHandle particlesTranslationJobHandle = particlesTranslationJob.Schedule(particleCount, 64, inputDeps);
4.  
5.             ComponentDataFromEntity<SPHVelocity> particlesVelocityJob = new ComponentDataFromEntity<SPHVelocity>();
6.             JobHandle particlesVelocityJobHandle = particlesVelocityJob.Schedule(particleCount, 64, inputDeps);
7.  
8.             ComponentDataFromEntity<SPHCollider> copyCollidersJob = new ComponentDataFromEntity<SPHCollider>();
9.             JobHandle copyCollidersJobHandle = copyCollidersJob.Schedule(colliderCount, 64, inputDeps);

The original looks like this:

Code (CSharp):

1.             // Copy the component data to native arrays
2.             CopyComponentData<Position> particlesPositionJob = new CopyComponentData<Position> { Source = positions, Results = particlesPosition };
3.             JobHandle particlesPositionJobHandle = particlesPositionJob.Schedule(particleCount, 64, inputDeps);
4.  
5.             CopyComponentData<SPHVelocity> particlesVelocityJob = new CopyComponentData<SPHVelocity> { Source = velocities, Results = particlesVelocity };
6.             JobHandle particlesVelocityJobHandle = particlesVelocityJob.Schedule(particleCount, 64, inputDeps);

the error for these is: cannot convert from 'int' to 'Unity.Collections.NativeMultiHashMaps<int, int>'

Would appreciate any help and explanation!

 

Code (CSharp):

1.  // Cache the data
2.             NativeArray<Translation> translations = SPHCharacterGroup.ToComponentDataArray<Translation>(Allocator.TempJob, out transDeps);
3.             NativeArray<SPHVelocity> velocities = SPHCharacterGroup.ToComponentDataArray<SPHVelocity>(Allocator.TempJob, out velsDeps);
4.             inputDeps = JobHandle.CombineDependencies(inputDeps, transDeps, velsDeps);

ToComponentDataArray copies the components to NativeArrays. CopyFromComponentDataArray writes the NativeArray values back to the entities at the same indices that are assigned in ToComponentDataArray.

Use GetComponentDataFromEntity to get a ComponentDataFromEntity if you need random access based on an Entity input.

 

Thank you for your answer, if you don't mind could you please explain your addition of transdeps and velsdeps please? I am unsure as to what their purpose is. Right now I've had to add them as global private JobHandles.

Also I still have the error: Assets\Scripts\ECS\SPHSystem.cs(408,74): error CS1503: Argument 2: cannot convert from 'int' to 'Unity.Collections.NativeMultiHashMap<int, int>'

So far I have not found a solution to this.

 

.ToCDA() uses a job to create the native array, if you omit the job handle, it will call .complete & create a sync point - if you supply a job handle, it will chain the dependencies and complete the jobs as required by their dependencies

 

Code? An error means very little if we can't look at the exact line the error message tells us to look at as well as the preceding context.