Question by z3nth10n · Mar 07, 2018 at 03:03 PM · texture2d terraindata heightmaps

Transporting image to terrain

Well I'm trying to transport an image to a terrain, I made this simple example:

 using UnityEngine;

 public class TerrainExample : MonoBehaviour
 {
     public Texture2D map, grassTexture;
     public float amp = 8;
     public Color waterColor = new Color(0.427f, 0.588f, 0.737f); //new Color32(127, 168, 200, 255); //0.427, 0.588, 0.737
 
     private Vector3 mapPlane = new Vector3(4200, 0, 3000);
 
     public void Start()
     {
         GameObject TerrainObj = new GameObject("TerrainObj");
         TerrainData _TerrainData = new TerrainData();
         Debug.Log(new Vector3(mapPlane.x, 600, mapPlane.z));
         _TerrainData.size = new Vector3(mapPlane.x / (1.6f * amp), 600, mapPlane.z / (1.6f * amp));
         _TerrainData.heightmapResolution = 4096;
         _TerrainData.baseMapResolution = 1024;
         _TerrainData.SetDetailResolution(1024, 16);

         //Set terrain data
         int _heightmapWidth = _TerrainData.heightmapWidth,
             _heightmapHeight = _TerrainData.heightmapHeight;
         float[,] heights = new float[_heightmapWidth, _heightmapHeight];
         float stepX = (float)map.width / _heightmapWidth, stepY = (float)map.height / _heightmapHeight;
         int w = 0;
         for (float i = 0; i < map.width; i += stepX)
             for (float k = 0; k < map.height; k += stepY)
             {
                 int ii = (int)i, kk = (int)k, i2 = (int)(i / stepX), k2 = (int)(k / stepY);
                 heights[i2, k2] = map.GetPixel(ii, kk) == waterColor ? .25f : .5f;
             }
         _TerrainData.SetHeights(0, 0, heights);

         //Set terrain grass texture
         SplatPrototype terrainTexture = new SplatPrototype();
         terrainTexture.texture = grassTexture;
         SplatPrototype[] splatPrototype = new SplatPrototype[1] { terrainTexture };
         _TerrainData.splatPrototypes = splatPrototype;
         TerrainCollider _TerrainCollider = TerrainObj.AddComponent<TerrainCollider>();
         Terrain _Terrain2 = TerrainObj.AddComponent<Terrain>();
         _TerrainCollider.terrainData = _TerrainData;
         _Terrain2.terrainData = _TerrainData;
         TerrainObj.transform.position = -mapPlane * 10 / 2 + Vector3.up * 100;
     }
 }

My map texture is the following:

map

The original map has 7000x5000 px, and my heightmap has 4096 units. So, I have to make a little translation, by calculating the step of every iteration (as you can see in line 25)

What I do is simple, I only put a 0.25f of the height (600/4 = 150) when there is water and 0.5f of the height (600 / 2 = 300) when there is something different from water. (Line 31)

But for some reason I only get this weird lines across the terrain:

problem