Mapping PerlinNoise to a Grid-CodePudding

I am trying to generate a grid across my map and add nodes depending on the perlin noise value. Depending on the value obtained from the perlin noise at a location, I will add a new Node which will be of a certain type e.g. Mountain, Water etc to represent terrian. Here I am trying to make it so that if the value is > 0.5, this mean it's only mountains and so a black coloured cubes should surround the mountain areas, However, my black cubes do not match the mountain areas from the perlin noise and I cannot seem to figure out why I am going wrong. Would appreciate any insight into how I could go about achieving this.

private void LocateWalkableCells()
{
    for(int z = 0; z < Height; z  )
    {
        for(int x = 0; x < Width; x  )
        {
            noise = GetNoiseValue(x, z);
            if(noise > 0.5) {
                grid[x,z] = new Node(new Vector3(x, 0, z), TerrainType.Mountain, 1);
            } 
            else {
                grid[x,z] = new Node(new Vector3(x, 0, z), TerrainType.Grass, 1);
            }
        }
    }
}

private float GetNoiseValue(int x, int z)
{
    int pos = (x * Width)   z;
    return Mathf.Round(terrainGenerator.noiseArray[pos] * 10) / 10;
}

// Draw gizmos to visualize colour
void OnDrawGizmos()
{
    Gizmos.DrawWireCube(transform.position, new Vector3(Width, 1, Height));
    if(grid != null)
    {
        foreach(Node n in grid)
        {
            if(n.TerrainType == TerrainType.Grass)
            {
                Gizmos.color = Color.green;
            } 
            else if(n.TerrainType == TerrainType.Mountain)
            {
                Gizmos.color = Color.black;
            } 

            Gizmos.DrawCube(n.Position, Vector3.one * (nodeDiameter - .1f));
        }
    }
}

noiseArray is used for the vertices of the terrain in the following code:

vertices = new Vector3[(Width   1) * (Depth   1)];
noiseArray = PerlinNoise();

int i = 0;
for(int z = 0; z <= Depth; z  )
{
    for(int x = 0; x <= Width; x  )
    {
        var currentHeight = noiseArray[i];

        if(currentHeight > HeightThreshold)
        {
            currentHeight *= HeightMultiplier;
        }

        vertices[i] = new Vector3(x, currentHeight, z);
        i  ;
    }
}

Output

Result from suggested answer

Still seems to miss some mountain areas, colouring green instead of black.

CodePudding user response：

It think the issue is in

var pos = (x * Width)   z;

since x is you index on the width of the grid you would probably rather want

var pos = z * Width   x;

in other words you want to

skip z rows
each row has Width elements
then from there take the xth element

assuming your terrain is laid out row-wise.

Or if it is laid out column-wise (which is rather unusual but possible)

var pos = x * Height   z;

or in other words

skip x columns
each column has Height elements
then from there take the zth element

Update

Now that you have showed the terrain generation code it needs to be

var pos = z * (Width   1)   x;

since the terrain array has actually Width 1 elements per row.