Q: Set terrain to specific heights during runtime? Currently the terrain under the object the script is on, the terrain will go to the max height. Can i somehow have a variable to set it to a specified height?
I didn't try too much, because i don't know how this works all too good..
using System.Collections; using System.Collections.Generic; using
UnityEngine;

public class test : MonoBehaviour {

    public Terrain terr; // terrain to modify
    int hmWidth; // heightmap width
    int hmHeight; // heightmap height

    int posXInTerrain; // position of the game object in terrain width (x axis)
    int posYInTerrain; // position of the game object in terrain height (z axis)

    int size = 5; // the diameter of terrain portion that will raise under the game object
    float desiredHeight = 2; // the height we want that portion of terrain to be

    void Start()
    {

        terr = Terrain.activeTerrain;
        hmWidth = terr.terrainData.heightmapWidth;
        hmHeight = terr.terrainData.heightmapHeight;

    }

    void Update()
    {

        // get the normalized position of this game object relative to the terrain
        Vector3 tempCoord = (transform.position - terr.gameObject.transform.position);
        Vector3 coord;
        coord.x = tempCoord.x / terr.terrainData.size.x;
        coord.y = tempCoord.y / terr.terrainData.size.y;
        coord.z = tempCoord.z / terr.terrainData.size.z;

        // get the position of the terrain heightmap where this game object is
        posXInTerrain = (int)(coord.x * hmWidth);
        posYInTerrain = (int)(coord.z * hmHeight);

        // we set an offset so that all the raising terrain is under this game object
        int offset = size / 2;

        // get the heights of the terrain under this game object
        float[,] heights = terr.terrainData.GetHeights(posXInTerrain - offset, posYInTerrain - offset, size, size);

        // we set each sample of the terrain in the size to the desired height
        for (int i = 0; i < size; i++)
            for (int j = 0; j < size; j++)
                heights[i, j] = desiredHeight;


        // set the new height
        terr.terrainData.SetHeights(posXInTerrain - offset, posYInTerrain - offset, heights);

    }

}

I expect to have an input and have the height set to the inputted height.
Example:
input = 10
terrain under the object goes to 10
actual output:
input - 10
terrain under the object goes to 600

A: The heights you pass to SetHeights method should be between 0 and 1. 0 means 0, 1 means maximum height of the terrain.
var heightScale = 1.0f / terr.terrainData.size.y;
for (int i = 0; i < size; i++)
    for (int j = 0; j < size; j++)
       heights[i, j] = desiredHeight * heigthScale;

