Dynamically create grid-like plane?

Questions & Answers
1

What I’m trying to do

I’m trying to create a tool which creates a plane plane with a specific amount of subdivisions on the X and Y axis. (aka a grid)

What I’m having problems with

I can’t seem to figure out how to generate triangles/indices for my mesh.

This is the function which creates the mesh and generates all its values:

	private void CreateTerrain()
	{
		GameObject go = new GameObject(terrainName);
		MeshFilter mf = go.AddComponent<MeshFilter>();
		MeshRenderer mr = go.AddComponent<MeshRenderer>();

		Mesh mesh = new Mesh();
		List<Vector3> vertices = new List<Vector3>();
		List<int> triangles = new List<int>();

		Vector3[] face = new Vector3[] {
			new Vector3(0, 0, 0),
			new Vector3(1, 0, 0),
			new Vector3(1, 1, 0),
			new Vector3(0, 1, 0)
		};

		for (uint x = 0; x < terrainSize.x; x++)
		{
			for (uint y = 0; y < terrainSize.y; y++)
			{
				Vector3[] currentFace = new Vector3[] {
					new Vector3(0 + x, 0 + y, 0),
					new Vector3(1 + x, 0 + y, 0),
					new Vector3(1 + x, 1 + y, 0),
					new Vector3(0 + x, 1 + y, 0)
				};

				vertices.Add(currentFace[0]);
				vertices.Add(currentFace[1]);
				vertices.Add(currentFace[2]);
				vertices.Add(currentFace[3]);

				triangles.Add(0 + (int)x * (int)y);
				triangles.Add(1 + (int)x * (int)y);
				triangles.Add(2 + (int)x * (int)y);
				triangles.Add(0 + (int)x * (int)y);
				triangles.Add(2 + (int)x * (int)y);
				triangles.Add(3 + (int)x * (int)y);
			}
		}

		mesh.vertices = vertices.ToArray();
		mesh.triangles = triangles.ToArray();

		mf.mesh = mesh;
		mesh.RecalculateBounds();
		mesh.RecalculateNormals();
	}

However when calling this function it doesn’t seem to properly create the mesh shape that I want:

122407-index.png
122407-index.png727×479 31.6 KB

As you can see the shape isn’t anywhere close to a 10x10 plane/grid like it should be.

2

Faulty maths. Remember that 0*2 is 0, not 2, for example.

Do it with a vertexIndex variable like this:

int vertexIndex = 0;

for (uint x = 0; x < terrainSize.x; x++)
         {
             for (uint y = 0; y < terrainSize.y; y++)
             {
                 Vector3[] currentFace = new Vector3[] {
                     new Vector3(0 + x, 0 + y, 0),
                     new Vector3(1 + x, 0 + y, 0),
                     new Vector3(1 + x, 1 + y, 0),
                     new Vector3(0 + x, 1 + y, 0)
                 };
 
                 vertices.Add(currentFace[0]);
                 vertices.Add(currentFace[1]);
                 vertices.Add(currentFace[2]);
                 vertices.Add(currentFace[3]);
 
                 triangles.Add(0 + vertexIndex);
                 triangles.Add(1 + vertexIndex);
                 triangles.Add(2 + vertexIndex);
                 triangles.Add(0 + vertexIndex);
                 triangles.Add(2 + vertexIndex);
                 triangles.Add(3 + vertexIndex);

                vertexIndex += 4;
             }
         }