public class MapChunk
    {
        public int MapSize;

        public MapChunk(int size)
        {
            MapSize = size;
        }

        public struct MapChunkData
        {
            public float[] _mapChunk;
            public int Size { get; set; }

            public MapChunkData(MapChunk mapChunk)
            {
                _mapChunk = new float[mapChunk.MapSize];
                Size = mapChunk.MapSize;
            }

            public void Evaluate(int index)
            {
                for (int i = 0; i < Size; i++)
                {
                    _mapChunk[i] = Unity.Mathematics.noise.snoise(new Vector2(index, i));
                }
            }
        }
    }


    public struct MapChunkEvaluateJob : IJobParallelFor
    {
        public NativeArray<MapChunk.MapChunkData> chunks;

        public void Execute(int index)
        {
            var chunk = chunks[index];
            chunk.Evaluate(index);
            chunks[index] = chunk;
        }
    }

    private MapChunkEvaluateJob _job;
    private NativeArray<MapChunk.MapChunkData> _mapChunkDataArray;
    List<MapChunk> mapChunks = new List<MapChunk>();
    // wouldn't it be better if there was some heightmap array that the jobs wrote to directly?

    public void InitMapGeneratorJobs()
    {
        // setup
        MapChunk.MapChunkData[] mapChunkData = new MapChunk.MapChunkData[128];

        for (int i = 0; i < mapChunkData.Length; i++)
        {
            MapChunk mp = new MapChunk(128);
            mapChunks.Add(mp);
            mapChunkData[i] = new MapChunk.MapChunkData(mapChunks[i]);
        }

        _mapChunkDataArray = new NativeArray<MapChunk.MapChunkData>(mapChunkData, Allocator.Persistent);

        _job = new MapChunkEvaluateJob
        {
            chunks = _mapChunkDataArray
        };
    }

    public void RunMapGeneratorJobs()
    {
        var jobHandle = _job.Schedule(128, 1); // can this be better?
        jobHandle.Complete();

        float[,] parallelledHeightMap = new float[128, 128];

        // can this be better?
        for (int i = 0; i < 128; i++)
        {
            for (int j = 0; j < 128; j++)
            {
                parallelledHeightMap[i, j] = _job.chunks[i]._mapChunk[j]; // this???
            }
        }
    }