I dont know why im getting a null reference exception

Questions & Answers
1

My first script makes an array and fills it with objects:

IEnumerator CreateTerrain () 
	{
		for (int px=0; px<chunkSize; px++)
		{
			for (int pz=0; pz<chunkSize; pz++)
			{
				float Perlin1 = Mathf.PerlinNoise((px+ transform.position.x) /xScale, heightScale);
				float Perlin2 = Mathf.PerlinNoise((pz+ transform.position.z) /xScale, heightScale);
				
				int x = (int) Mathf.FloorToInt(px + transform.position.x);
				int height = (int) Mathf.FloorToInt(Perlin1*40*Perlin2);
				int z = (int) Mathf.FloorToInt(pz + transform.position.z);
				
				for (int y=0; y<height; y++)
				{
					yield return new WaitForSeconds (1/blocksPerSecond);
					GameObject currentBlock = GameObject.Instantiate(blocks[0], new Vector3(x, y, z), Quaternion.identity) as GameObject;
					currentBlock.transform.parent = transform;
					levelData[x, y, z] = currentBlock;
				}
			}
		}
		
		foreach (Transform block in transform)
		{
			block.GetComponent<BlockScript>().UpdateSides();
		}
	}

My Script that im getting the error on is:

public void UpdateSides () 
	{
		levelData = new GameObject[chunkSize, chunkHeight, chunkSize];
		
		levelData = leveldataScript.levelData; *** null reference exception ***
		
		print (levelData.GetLength(0) + " , " + levelData.GetLength(1) + " , " + levelData.GetLength(2));
		
		int x = (int) transform.position.x;
		int y = (int) transform.position.y;
		int z = (int) transform.position.z;
		// it continues.....

iv been trying to figure out why im getting the error but i have no idea. The console prints out: 10, 100, 10 which means that the array isnt null. Can anyone help please thank you

2

Probably because you have a null reference. The error means “something before a dot is null”. So go to the error line. Find all the dots. And check everything immediately before a dot has been assigned a value.