How would I flip or mirror Terrain data during runtime?

Question

I am trying to make a simple endless terrain illusion. Terrains don't scale at all with their transforms though, so I can't just use transform.scale(-1,0,0) to pull off making the clones needed for wrapping. So I'm now trying to create the terrain clones during runtime.

But I can't seem to get anyt$$anonymous$$ng returned from terrain.terrainData.GetHeights(0,0,w,h); If I debug.log that info, I just end up getting "System.Single[,]" instead of the array data. According to the docs, from what I understand that should be returning a 2d array of the terrain data, and certainly should not be returning an empty array, in any case.

Here's the full code below. All I get when running t$$anonymous$$s is the debug returning System.Single[,], followed by a IndexOutOfRangeException error. (The indexoutofrange is presumably because I have not gotten the data correctly in the first place) :

 //variables
 var terrainBase : TerrainData; //original terrain data, editor set.
 
 function Start () {
     terrain2A = Terrain.CreateTerrainGameObject(terrainBase);
     //scale 2A along the Z axis
     var t2ATerrain = terrain2A.GetComponent(Terrain) as Terrain;
     var h = t2ATerrain.terrainData.heightmapHeight;
     var w = t2ATerrain.terrainData.heightmapWidth;
     var oTerrain = t2ATerrain.terrainData.GetHeights(0,0,w,h);
     Debug.Log(oTerrain);
     t2ATerrain.terrainData.SetHeights(0,0,FlipTerrainX(oTerrain,w,h));
 }
 
 function FlipTerrainX(originalArray : float[,],heightmapX:float,heightmapY:float) {
     var nArray = new float[heightmapX,heightmapY];
     //Debug.Log(originalArray);
     //Debug.Log(nArray);
     for(var x = 0;x < heightmapX;x++) {
         for(var y = 0;y < heightmapY;y++) {
             //flip the x, but leave y matc$$anonymous$$ng
             nArray[heightmapX - x,y] = originalArray[x,y];
         }
     }
     return nArray;
 }

I'm sure I am just missing somet$$anonymous$$ng simple here.

All I want to do is be able to loop and process the array of heightmaps to mirror the terrain for the other 4 versions needed to loop it forever. T$$anonymous$$s error is a bit over my head, however, and searches are not being very helpful since the information I'm getting is very conflicting on if t$$anonymous$$s should even work.

Answer 1

Answer by hav_ngs_ru · Dec 16, 2014 at 08:02 AM

not sure about what in you terrainBase. Debug.Log w and h in Start function - what they have?

Add comment · Show 1 · Share

darkgriffin · Dec 16, 2014 at 07:28 PM 0

Share

h is 513, w is 513.

and this

Debug.Log(t2ATerrain.terrainData.GetHeights(0,0,w,h));

is also returning this

System.Single[,]

instead of data from in the array.

EDIT: The terrain I'm loading is currently just a default Unity terrain I made with the "GameObject - Terrain" menu option. Default settings, and blank except for a quick heightmap I scribbled on it in the editor to test with. So basically, I am failing to get data from the default terrain here.

Out of curiosity, I tried replacing w and h with numbers like 32, 45, and such other manually typed numbers. I still get blank arrays back. I also tried asking for data from 1,1,25,25 and got a blank back. So it appears that the call to GetHeights is always returning a blank for some reason, even though the terrain clearly exists during runtime.

Answer 2

Old I know... but t$$anonymous$$s was all that came up when I was searc$$anonymous$$ng for a solution so I thought I'd leave my answer here. Eventually figured it out. See below.

  public static IEnumerator FlipTerrain(Terrain terrain)
     {
         TerrainData terrainData = terrain.terrainData;
 
         int widthOfTerrain = terrainData.heightmapResolution;
 
         float[,] noiseMap = terrainData.GetHeights(0, 0, widthOfTerrain, widthOfTerrain);
         float[,] noiseMapFlipped = new float[widthOfTerrain, widthOfTerrain];
         
         int flipX = 0;
         int flipY = 0;
 
         for (int y = 0; y < widthOfTerrain; y++)
         {
             for (int x = 0; x < widthOfTerrain; x++)
             {
 
                 flipX = widthOfTerrain - 1 - x;
                 flipY = widthOfTerrain - 1 - y;
 
                 noiseMapFlipped[flipX, flipY] = noiseMap[x, y];
 
             }
         }
 
         terrainData.SetHeights(0, 0, noiseMapFlipped);
 
         yield return new WaitForEndOfFrame();
     }

How would I flip or mirror Terrain data during runtime?

2 Replies

Your answer

Welcome to Unity Answers

Follow this Question

Related Questions