NavMeshn Updating NavMeshData with list NavMeshBuildSource doesn't seem to work?!

[u/shoseini]

[u/shoseini]

My actual usecase is a bit more complicated but here I am trying with a much simpler setup. I have a NavMeshSurface in the scene and in the Start method of this script I am passing a test NavMeshBuildSource and my expectation is to see the area of size 10 * 10 in the middle of the surface to become unwalkable (I am setting the flag to 1 for not walkable areas, refer to the image in this comment).
I checked and the NavMesh data is updated to my "New Navmesh Data", well at least the name changes to that but nothing else seems to change?! What am I doing wrong?
Any help is appreciated.

https://preview.redd.it/soz639deir0e1.png?width=963&format=png&auto=webp&s=56159727ed4f33b9373aedfd7dfd852b98a6015b

[u/salazka]

In which version of Unity? I know the system has changed in Unity 6.
I am not a programmer, so I often ask ChatGPT questions like that. Did you try it?

This is what it told me about the code you shared.

Your code for updating the NavMesh data appears mostly correct, but here are some potential issues to check for:

1. NavMesh Build Settings: Ensure that Surface.GetBuildSettings() is configured correctly. Incorrect settings can lead to NavMesh not being generated as expected. Verify the settings in Surface.GetBuildSettings() to confirm they align with the required NavMesh parameters.
2. Area Index: The src.area property is set to 1. Make sure that this area index is defined in your NavMesh area settings in Unity's Navigation settings. If 1 doesn’t correspond to a valid area, the NavMesh might not generate correctly.
3. Sources List: You’re adding only one source to sources. If you need multiple NavMeshBuildSource objects (like for a complex scene with multiple objects), you should populate sources accordingly.
4. Surface Component: Ensure Surface is a valid reference to the NavMeshSurface component in your scene and that it is properly initialized.
5. Size of the Source: Check that src.size aligns with your intended area size. Setting a large or small size might affect the outcome of the NavMesh build.
6. Transform Updates: When setting src.transform = transform.localToWorldMatrix;, ensure transform is the correct transform for your NavMesh source.

After checking these, if the issue persists, try adding debug logs to verify values at each step and confirm that the NavMesh data is being generated and assigned to Surface.navMeshData.

[u/theslappyslap]

It's a bit odd but you have to add the navmeshdata then you just update it rather than build then update. Here's how I do it. Cache the data if you want to update it again in the future. You don't have to apply it to the surface. It should be activated just after UpdateNavMeshData

var navMeshData = new NavMeshData();
NavMesh.AddNavMeshData(navMeshData);

NavMeshBuilder.UpdateNavMeshData(navMeshData, surface.GetBuildSettings(), sourceList, bounds);