SE File Loading

byte[] fileData = r.ReadBytes(bytesRemaining);
var b = 0;

for (int x = 0; x < Constants.MapSizeX; x++)
{
    int chunkX = x / Constants.ChunkSize;

    for (int z = 0; z < Constants.MapSizeZ; z++)
    {
        int chunkZ = z / Constants.ChunkSize;

        // Data inside each chunk is stored in a 1D array, so pre-calculate the horizontal array access here to avoid expensive % and * operations in the inner loops
        int xzAccess = (x % Constants.ChunkSize) * Constants.ChunkSize + (z % Constants.ChunkSize) * Constants.ChunkSizeSquared;

        // Map-Coordinate Y, tracks our vertical position in the column
        int mapY = 0;

        // Get the amount of block types in this column
        byte columnCount = fileData[b++];

        for (int i = 0; i < columnCount; i++)
        {
            // Get the block type and how tall this section of the column is
            var type = fileData[b++];
            byte amount = fileData[b++];

            // If it's an empty column, there's no need to modify the chunk data.
            if (type == 0)
            {
                mapY += amount;
                continue;
            }

            int chunkY = mapY / Constants.ChunkSize;

            // Get the chunk and initialise it if needed
            ChunkBase c = m.chunks[chunkX, chunkY, chunkZ];
            if (c == null)
                c = m.InitChunk(chunkX, chunkY, chunkZ);

            // Chunk-Coordinate Y
            int yAccess = mapY % Constants.ChunkSize;

            int top = mapY + amount;
            for (int j = mapY; j < top; j++)
            {
                // If we have moved up into a new chunk
                if (yAccess == Constants.ChunkSize)
                {
                    chunkY++;

                    c = m.chunks[chunkX, chunkY, chunkZ];
                    if (c == null)
                        c = m.InitChunk(chunkX, chunkY, chunkZ);

                    yAccess = 0;
                }

                // Get a reference to the block and update it
                ref var block = ref c.data[xzAccess + yAccess];
                block.index = type;
                block.health = 100;

                yAccess++;
            }

            mapY += amount;
        }

        // Update the height map
        m.maxY[x, z] = (byte)mapY;
    }
}