# Mesh based on noise

I have been trying to generate a mesh based on some noise, and I want to say if the noise is 0 don’t generate a vertices. But the problem is that the mesh will end up look really weird because of the way I generate my triangles.

Code:

``````    private void CreateMesh()
{
var m = new RidgeNoise(Random.seed);
m.OctaveCount = 2;
m.Frequency = 0.01f;

int hw = Terrain.activeTerrain.terrainData.heightmapWidth;
float[,] heightmap = Terrain.activeTerrain.terrainData.GetHeights(0, 0, hw, hw);

int ChunkWidth = hw / 8;
int ChunkCount = hw / ChunkWidth;

float scale = Terrain.activeTerrain.terrainData.size.x / hw;

Vector2 uvScale = new Vector2(1.0f / hw, 1.0f / hw);

for (int cx = 0; cx < ChunkCount; cx++)
{
for (int cy = 0; cy < ChunkCount; cy++)
{
int CW = hw / ChunkCount;
GameObject water = new GameObject();
Vector3 p = new Vector3(cx * ChunkWidth, 0f, cy * ChunkWidth);

water.transform.localScale = new Vector3(scale, 0.95f, scale);
water.transform.position = new Vector3(cx * (ChunkWidth * scale), 0f, cy * (ChunkWidth * scale));
water.name = "Water";
water.transform.parent = Terrain.activeTerrain.transform;

water.AddComponent<MeshRenderer>();
Mesh w = new Mesh();
MeshFilter mf = water.AddComponent<MeshFilter>();

Vector3[] tVertices = new Vector3[(CW + 1) * (CW + 1)];
Vector2[] tUV = new Vector2[tVertices.Length];
int[] triangles = new int[tVertices.Length * 6];

for (int y = 0; y < CW; y++)
{
for (int x = 0; x < CW; x++)
{
Vector2 curPos = new Vector2((p.x + x), (p.z + y));
float height = heightmap[(int)curPos.y, (int)curPos.x] * Terrain.activeTerrain.terrainData.size.y;
if (height < WaterLevel)
{
height = WaterLevel;
}

float v = Mathf.Max(0f, m.GetValue(curPos.x, curPos.y, 0f) - 0.875f) / 25.0f;

map.SetPixel((int)curPos.x, (int)curPos.y, Color.white * (v * 25));
if (v != 0)
{
tVertices[y * CW + x] = new Vector3(x, height, y);
tUV[y * CW + x] = Vector2.Scale(new Vector2(x, y), uvScale);
heightmap[(int)curPos.y, (int)curPos.x] -= v;

}
}
}

int index = 0;
for (int y = 0; y < CW - 1; y++)
{
for (int x = 0; x < CW - 1; x++)
{
triangles[index] = (y * CW) + x;
triangles[index + 1] = ((y + 1) * CW) + x;
triangles[index + 2] = ((y + 1) * CW) + x + 1;

triangles[index + 3] = (y * CW) + x;
triangles[index + 4] = ((y + 1) * CW) + x + 1;
triangles[index + 5] = (y * CW) + x + 1;
index += 6;
}
}

w.vertices = tVertices;
w.uv = tUV;
w.triangles = triangles;

w.RecalculateNormals();
w.Optimize();

mf.mesh = w;
}
}
}
``````

Noise:

Result:

If I understand correctly, you simply want to make terrain based on a texture? You can do this very easily by converting your image into a RAW file, and importing it by selecting “Import Raw…” towards the bottom of the settings tab after selecting the terrain GameObject.

You can use Photoshop to convert an image to RAW format, or use a free online converter.