Version: Unity 6.1 Alpha (6000.1)
LanguageEnglish
  • C#

ReadOnlyAttribute

class in Unity.Collections

/

Implemented in:UnityEngine.CoreModule

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Description

Marks a member of a struct used in a job as read-only.

Native containers are read-write by default when used in a job. This means that you can't schedule two jobs that reference the same containers simultaneously. Add the ReadOnly attribute to a native container field in a job struct to mark the container as read-only. This allows two jobs to run in parallel and read data from the same native container.

Additional resources: IJob, IJobParallelFor.

using Unity.Jobs;
using Unity.Collections;
using UnityEngine;

public struct MyJob : IJob { [ReadOnly] public NativeArray<int> input;

public NativeArray<int> output;

public void Execute() { for (var i = 0; i < output.Length; ++i) output[i] = input[i]; } }

public class ParallelReplicator : MonoBehaviour { public void OnUpdate() { const int n = 10000; var original = new NativeArray<int>(n, Allocator.Persistent); var clone1 = new NativeArray<int>(n, Allocator.Persistent); var clone2 = new NativeArray<int>(n, Allocator.Persistent);

var job1 = new MyJob { input = original, output = clone1 }; var job2 = new MyJob { input = original, output = clone2 };

var jobX = new MyJob { input = original, output = clone2 };

// Run the jobs in parallel. var jobs = JobHandle.CombineDependencies(job1.Schedule(), job2.Schedule());

// jobX.Schedule(); // Not allowed, throws exception because job2 is writing into clone2.

jobs.Complete();

jobX.Schedule().Complete(); // Allowed, because job2 has been completed by now.

original.Dispose(); clone1.Dispose(); clone2.Dispose(); } }