Create Mesh Object from Navmesh

General Navmesh graph
1

Hi ,

i edited my NavMesh Gaph via code and now want to use the modifided NavMeshGraph for Debugging purposes. Is there any way to create a Mesh Object from the NavMesh ?

2

Hi

There’s no exposed function for this. But something like this could work:

public static void ExportToFile (NavmeshBase target) {
	//INavmesh graph = (INavmesh)target;
	if (target == null) return;

	NavmeshTile[] tiles = target.GetTiles();

	if (tiles == null) {
		if (EditorUtility.DisplayDialog("Scan graph before exporting?", "The graph does not contain any mesh data. Do you want to scan it?", "Ok", "Cancel")) {
			AstarPathEditor.MenuScan();
			tiles = target.GetTiles();
			if (tiles == null) return;
		} else {
			return;
		}
	}

	string path = EditorUtility.SaveFilePanel("Export .obj", "", "navmesh.obj", "obj");
	if (path == "") return;

	//Generate .obj
	var sb = new System.Text.StringBuilder();

	string name = System.IO.Path.GetFileNameWithoutExtension(path);

	sb.Append("g ").Append(name).AppendLine();

	//Vertices start from 1
	int vCount = 1;

	//Define single texture coordinate to zero
	sb.Append("vt 0 0\n");

	for (int t = 0; t < tiles.Length; t++) {
		NavmeshTile tile = tiles[t];

		if (tile == null) continue;

		var vertices = tile.verts;

		//Write vertices
		for (int i = 0; i < vertices.Length; i++) {
			var v = (Vector3)vertices[i];
			sb.Append(string.Format("v {0} {1} {2}\n", -v.x, v.y, v.z));
		}

		//Write triangles
		TriangleMeshNode[] nodes = tile.nodes;
		for (int i = 0; i < nodes.Length; i++) {
			TriangleMeshNode node = nodes[i];
			if (node == null) {
				Debug.LogError("Node was null or no TriangleMeshNode. Critical error. Graph type " + target.GetType().Name);
				return;
			}
			if (node.GetVertexArrayIndex(0) < 0 || node.GetVertexArrayIndex(0) >= vertices.Length) throw new System.Exception("ERR");

			sb.Append(string.Format("f {0}/1 {1}/1 {2}/1\n", (node.GetVertexArrayIndex(0) + vCount), (node.GetVertexArrayIndex(1) + vCount), (node.GetVertexArrayIndex(2) + vCount)));
		}

		vCount += vertices.Length;
	}

	string obj = sb.ToString();

	using (var sw = new System.IO.StreamWriter(path)) {
		sw.Write(obj);
	}
}
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