Unity 3D Procedural Terrain - Step 1 - Sine Wave

using UnityEngine;
using System.Collections;

public class TerrainStuff : MonoBehaviour {

    Terrain terrain;

    // Use this for initialization
    void Start () {
        terrain = GetComponent<Terrain>();

        TerrainData data = terrain.terrainData;

        float[,] heights = data.GetHeights(0, 0, data.heightmapWidth, data.heightmapHeight);

        for( int x=0; x<512; ++x)
        {
            for( int z=0; z<512; ++z)
            {
                heights[x,z] = Mathf.Sin ( x*0.05f ) * 0.2f + 0.2f;

                if (z==0) { Debug.Log(heights[x,z]); }

            }
        }

        data.SetHeights(0, 0, heights);

    }


}