UnityBurstFunctions

Pattern and helpers for writing Unity Burst jobs as generic Functions/Actions.

Write burst compiled jobs with easy arguments and return values.

    [BurstCompile]
    public struct AddIntegersFuncX2 : IBurstFunction<int, int, int>
    {
        public int Execute(int a, int b)
        {
            return a + b;
        }

        public static int Invoke(int a, int b)
        {
            return BurstFunction<AddIntegersFuncX2, int, int, int>.Run(Instance, a, b);
        }

        private static readonly AddIntegersFuncX2 Instance = new AddIntegersFuncX2();
    }

then call it like a normal function.

 var intResult3 = MyFunctions.AddIntegersFuncX2.Invoke(5, 7);

View as normal in the Burst Inspector

Still reasonably fast.

Pass complicated arguments

    [BurstCompile]
    public struct ArrayTestFunc : IBurstFunction<NativeArray<int>, NativeArray<int>, NativeArray<int>>
    {
        public NativeArray<int> Execute(NativeArray<int> arg1, NativeArray<int> arg2)
        {
            for (int i = 0; i < 100000; i++)
            {
                arg1[i] = i;
            }
            for (int i = 0; i < 100000; i++)
            {
                arg2[i] = arg1[i];
            }
            return arg2;
        }

        public static NativeArray<int> Invoke(NativeArray<int> a, NativeArray<int> b)
        {
            return BurstFunction<ArrayTestFunc, NativeArray<int>, NativeArray<int>, NativeArray<int>>.Run(Instance, a, b);
        }

        public static ArrayTestFunc Instance { get; } = new ArrayTestFunc();
    }

Pass by reference ('unmanaged' types only)

Interface:

	public interface IBurstRefAction<T1, T2, T3, T4, T5> : IBurstOperation
	{
		void Execute(ref T1 arg1, T2 arg2, T3 arg3, T4 arg4, T5 arg5);
	}

Implementation:

    [BurstCompile]
    public struct TryGetContact : IBurstRefAction<NativeManifold, RigidTransform, NativeHull, RigidTransform, NativeHull>
    {
        public void Execute(ref NativeManifold manifold, RigidTransform t1, NativeHull hull1, RigidTransform t2, NativeHull hull2)
        {
            HullIntersection.NativeHullHullContact(ref manifold, t1, hull1, t2, hull2);
        }

        public static bool Invoke(out NativeManifold result, RigidTransform t1, NativeHull hull1, RigidTransform t2, NativeHull hull2)
        {
            // Can only allocate as 'temp' within Burst Jobs 
            result = new NativeManifold(Allocator.Persistent); 

            BurstRefAction<TryGetContact, NativeManifold, RigidTransform, NativeHull, RigidTransform, NativeHull>.Run(Instance, ref result, t1, hull1, t2, hull2);
            return result.Length > 0;
        }

        public static TryGetContact Instance { get; } = new TryGetContact();
    }

Calling Example:

	var burstResult = HullOperations.TryGetContact.Invoke(out NativeManifold manifold, t1, hull1, t2, hull2);