为什么会给我一个错误，提示并非所有代码路径都返回一个值

Question

这是我的代码：（我认为函数vector中的PopulateVoxelMap与之有关]

public class Chunk
{

    public ChunkCoord coord;

    GameObject chunkObject;
    MeshRenderer meshRenderer;
    MeshFilter meshFilter;

    int vertexIndex = 0;
    List<Vector3> vertices = new List<Vector3>();
    List<int> triangles = new List<int>();
    List<Vector2> uvs = new List<Vector2>();

    byte[,,] voxelMap = new byte[VoxelData.ChunkWidth, VoxelData.ChunkHeight, VoxelData.ChunkWidth];

    World world;

    public Chunk (ChunkCoord _coord, World _world)
    {

        coord = _coord;
        world = _world;
        chunkObject = new GameObject();
        meshFilter = chunkObject.AddComponent<MeshFilter>();
        meshRenderer = chunkObject.AddComponent<MeshRenderer>();

        meshRenderer.material = world.material;
        chunkObject.transform.SetParent(world.transform);
        chunkObject.transform.position = new Vector3(coord.x * VoxelData.ChunkWidth, 0f, coord.z * VoxelData.ChunkWidth);
        chunkObject.transform.name = "Chunk " + coord.x + ", " + coord.z;

        PopulateVoxelMap();
        CreateMeshData();
        CreateMesh();
    }


    void PopulateVoxelMap()
    {
        for (int y = 0; y < VoxelData.ChunkHeight; y++)
        {
            for (int x = 0; x < VoxelData.ChunkWidth; x++)
            {
                for (int z = 0; z < VoxelData.ChunkWidth; z++)
                {
                    voxelMap[x, y, z] = world.GetVoxel(new Vector3(x, y, z));
                }
            }
        }
    }

    void CreateMeshData()
    {
        for (int y = 0; y < VoxelData.ChunkHeight; y++)
        {
            for (int x = 0; x < VoxelData.ChunkWidth; x++)
            {
                for (int z = 0; z < VoxelData.ChunkWidth; z++)
                {

                    AddVoxelDataToChunk(new Vector3(x, y, z));

                }
            }
        }
    }


    public bool isActive
    {
        get { return chunkObject.activeSelf; }
        set { chunkObject.SetActive(value); }
    }

    public Vector3 position
    {
        get { return chunkObject.transform.position; }
    }


    bool IsVoxelInChunk(int x, int y, int z)
    {
        if (x < 0 || x > VoxelData.ChunkWidth - 1 || y < 0 || y > VoxelData.ChunkHeight - 1 || z < 0 || z > VoxelData.ChunkWidth - 1)
            return false;
        else
            return true;
    }

    bool CheckVoxel(Vector3 pos)
    {
        int x = Mathf.FloorToInt(pos.x);
        int y = Mathf.FloorToInt(pos.y);
        int z = Mathf.FloorToInt(pos.z);

        if (!IsVoxelInChunk(x, y, z))
            return false;
    }


    void AddVoxelDataToChunk(Vector3 pos)
    {
        for (int p = 0; p < 6; p++)
        {
            if (!CheckVoxel(pos + VoxelData.faceChecks[p]))
            {

                byte blockID = voxelMap[(int)pos.x, (int)pos.y, (int)pos.z];

                vertices.Add(pos + VoxelData.voxelVerts [VoxelData.voxelTris [p, 0]]);
                vertices.Add(pos + VoxelData.voxelVerts [VoxelData.voxelTris [p, 1]]);
                vertices.Add(pos + VoxelData.voxelVerts [VoxelData.voxelTris [p, 2]]);
                vertices.Add(pos + VoxelData.voxelVerts [VoxelData.voxelTris [p, 3]]);

                AddTexture(world.blocktypes[blockID].GetTextureID(p));

                triangles.Add (vertexIndex);
                triangles.Add (vertexIndex + 1);
                triangles.Add (vertexIndex + 2);
                triangles.Add (vertexIndex + 2);
                triangles.Add (vertexIndex + 1);
                triangles.Add (vertexIndex + 3);
                vertexIndex += 4;
            }
        }
    }

    void CreateMesh()
    {
        Mesh mesh = new Mesh();
        mesh.vertices = vertices.ToArray();
        mesh.triangles = triangles.ToArray();
        mesh.uv = uvs.ToArray();

        mesh.RecalculateNormals();

        meshFilter.mesh = mesh;
    }

    void AddTexture(int textureID)
    {
        float y = textureID / VoxelData.TextureAtlasSizeInBlocks;
        float x = textureID - (y * VoxelData.TextureAtlasSizeInBlocks);

        x *= VoxelData.NormalizedBlockTextureSize;
        y *= VoxelData.NormalizedBlockTextureSize;

        y = 1f - y - VoxelData.NormalizedBlockTextureSize;

        uvs.Add(new Vector2(x, y));
        uvs.Add(new Vector2(x, y + VoxelData.NormalizedBlockTextureSize));
        uvs.Add(new Vector2(x + VoxelData.NormalizedBlockTextureSize, y));
        uvs.Add(new Vector2(x + VoxelData.NormalizedBlockTextureSize VoxelData.NormalizedBlockTextureSize));
    }

Answer 1

CheckVoxel不在所有代码路径上返回有效的布尔值。返回true的位置在哪里？该方法的正确版本可能是：布尔CheckVoxel（Vector3 pos）{int x = Mathf.FloorToInt（pos.x）;int y = Mathf.FloorToInt（pos.y）;int z = Mathf.FloorToInt（pos.z）;

    if (!IsVoxelInChunk(x, y, z))
        return false;

    return true;
}

但是可以简单地重写为：

bool CheckVoxel(Vector3 pos)
{
    int x = Mathf.FloorToInt(pos.x);
    int y = Mathf.FloorToInt(pos.y);
    int z = Mathf.FloorToInt(pos.z);

    return IsVoxelInChunk(Mathf.FloorToInt(pos.x),
                          Mathf.FloorToInt(pos.y),
                          Mathf.FloorToInt(pos.z));
}

Answer 2

bool CheckVoxel(Vector3 pos)
{
    int x = Mathf.FloorToInt(pos.x);
    int y = Mathf.FloorToInt(pos.y);
    int z = Mathf.FloorToInt(pos.z);

    if (!IsVoxelInChunk(x, y, z))
        return false;
}

例如，在此函数中，仅当！IsVoxelInChunk（x，y，z）时才返回。给定该函数是否返回false，该函数返回false，请更改：

if (!IsVoxelInChunk(x, y, z))
            return false;

至：

return IsVoxelInChunk(x, y, z);