为什么线程在获取二维数组值后停止？

Question

I am very new to threading in C# and I can't figure out why my thread is stopping in the middle of the execution.

I have build my own terrain solution in Unity3d. The terrain is composed of chunks. Each chunk's mesh should be updated on a thread so there aren't any significant frame drops during play.

I create a thread that calls UpdateChunkMeshData with some parameters. Any time I try to access my 2d array of chunks in the Thread it stops. Why would this happen?

Shorted version of the code:

public Chunk[,] Chunks;


public class Chunk
{
    public GameObject gameObject;
    public float[,] Heights;
    public int Resolution;

    public bool NeedsToUpdate;
    public bool Busy;
    public bool MeshReady;

}


for (int x = 0; x < ChunkCountX; x++)
{
    for (int y = 0; y < ChunkCountY; y++)
    {

        Thread thread = new Thread(() => {
                                Debug.Log("Starting thread for chunk " + ChunkIndexX + ", " + ChunkIndexY);
                                UpdateChunkMeshData(x, y, Resolution, false, false, false, false);
                                Debug.Log("Finished thread for chunk " + ChunkIndexX + ", " + ChunkIndexY);
                               });


        thread.Start();
    }
}


private void UpdateChunkMeshData(int ChunkX, int ChunkY, int someOtherParams)
{
    Debug.Log("Thread started fine");

    // As soon as I try to access any of the chunks in the array the thread stops. I don't get any errors either.
    Debug.Log(Chunk[ChunkX, ChunkY].Heights[x, y]);

    Debug.Log("Thread doesn't print this");
}

Answer 1

Arrays are not Thread-Safe. For more information: array and safe access by threads .

If you have some locking in your Chunk you might be facing a deadlock.

Why do you use so many threads? I guess it might be better to create one thread and update all your chunks in one thread.