Navmesh Editing with 3dsmax

Based on original tutorial by Outlawz

This tutorial requires you to have a generated navmesh to work with.

Tools: 3ds Max (any version) and Notepad.

Note: This tutorial uses 3ds Max 9, but newer versions of 3ds Max will work for editing Navmeshes since is in the standard wavefront obj format. 3ds Max 9 is used in the tutorial because that was the last version that supports BF2 plugins and is required for importing or exporting models with the BF2 format.

**Getting Setup:**

 To start, open 3ds Max and once loaded, go to File>Import.
Navigate to your map's output folder.
The import directory can be configured so you don't have to browse through half your HDD to get to your files.

Don't forget to select the file type to be .obj, otherwise you won't see your files.
When you'll open the file, 3ds max will ask your for import settings. Also, don't forget the Material Library string needs to be manual entered as materials.mtl. For those settings can be found here:

3dsMax Navmesh Import

**Editing:**
Your navmesh will now open in a new scene with four views, select the Perspective (bottom right) one and go to the bottom right of the program, where there's a toolbar which contains tools that you can use to navigate around your object.

* Select the Maximize Viewport Toggle as shown by the arrow, then select your navmesh object.

Right-click on your selected navmesh and go Convert To>Editable Poly

You may have noticed a toolbar on the right side before. Once you have converted the object, go there and under Selection, pick Element.

Select the main part of your navmesh, the one you want to keep

Now go to Edit>Select Invert

Now everything else you didn't select is selected. Press Delete and all those evil useless navmesh islands will go away. Note: this also deletes manifolds, since faces have to be connected by an edge to "qualify", not just by a vertex

This concludes the basic deletion of mesh islands. You can now skip to exporting, or stick around for more

**Removing faces**

If you want to remove parts of the mesh you don't want to use, then go to Selection and select Face (next to Element from before).

Select the faces you want to remove and press Delete.

**Moving vertices**

 Select Vertex mode either from the icon or the list under the Edit Poly modifier.
Right-click on 'Perspective in the top left of the viewport and change the view to Wireframe.

 Select the Move tool, then select the vertice you want to move.

Extracting materials out of the mesh for later use

 Note: When extruding new faces in 3ds Max the materials are carried over.
This might be useful if you somehow lose your materials.

Press M to bring up the Material editor and click 'Get material from selection' (eyedropper tool) then click on the mesh in the viewport.

The materials are carried over into the Material editor.

**Adding new faces**

Unlike Maya, materials are carried over from the extruded mesh, however if you find yourself extruding ie. deep water mesh and want it to be shallow/ground mesh, you can use the above technique for material extraction to add new materials to faces.

First, convert your navmesh to Editable Mesh (not Poly)

Select the Edge tool and pick an edge you want to extrude.

Edges can only be extruded up or down or left or right for some reason, so don't panic; with the edge still selected, use the Select&Move tool to move the edge up/down/left/right to align it with the rest.
Having preopt loaded is recommended, so you can better adjust the faces.

**Converting quad faces to triangles**

Again unlike Maya, there doesn't seem to be a magic 'turn quads to triangles' option, so I found a very simple solution for this one. Convert your mesh to Editable Poly, select two opposite vertices,

Then under Edit Vertices click Connect,

and you're done.

**Adding detail to your faces**

In case you've got an enormous face and want it in smaller parts to align it better with the terrain, do the following.
Convert your mesh to Editable Mesh (unless you're already it that mode) and select the face.

Then scroll down in the Edit geometry to Tesselate, you can play with the amount and two options, Edge and Face-Center.Edge does this:

And Face-Center does this.

I prefer the latter, as you only need to connect the two opposing vertices in the middle quad and you're good to go.

Exporting:
Go to File>Export and save over the file you opened before as .obj, 3ds max will ask you for export settings, set them according to these:

* 3dsMax Navmesh Export

This is to add back the materials, in case they get lost by 3ds Max.

You can now go onto the next step:

* Fixing the Navmesh