So I created a new C++ Top down project and loaded it up.
I then deleted the four walls and launched the game. I noticed that the player character does not walk to the edges of the map. Expanding the NavMesh does not make any difference.
Trying to change the dimensions of the floor actor does something strange. If any of the x/y/z values are not set to 200, it changes shape to the specified size.
If it is expanded out, say 10,000x10,000x200, and the NavMesh is also expanded out, the player character still does not want to go outside the original bounds.
Make sure that you Build your level so the navigation is rebuilt. Once you do this, the character will run anywhere the navmesh is active. To see the navmesh in action while in the editor, toggle it visible with the P key.
Thanks, I see what’s happening now. It looks like the brushes which I removed are still being included in the nav mesh.
In fact, I deleted everything from the Scene outliner except the Floor brush and th NavMeshBoundsVolume1 and did a build. The NavMesh still takes into account all the brushes that used to be in the scene.
Enabling Edit → Project Settings → Engine → Navigation Mesh → Rebuild at Runtime makes no difference either.
When the navmesh is created in the level, it also creates a RecastNavMesh asset. If you deleted everything but the floor and the navmesh, that could be causing the issue. Try creating a fresh project, delete the walls, expand the floor, expand the navmesh, and then build.
I just created a new top down c++ project, loaded the editor, deleted the walls and pressed p to check the navmesh. There are gaps where the walls used to be.
Doing a build does not change. Deleting one of the boxes makes the NavMesh go red temporarily, then back to green but with a gap where the box was.
After hitting Play, the character does not move over the space where the box was, nor does it move past where the walls used to.
I tried deleting the Nav Mesh Volume and creating a new one - and that too for some reason has gaps where these brushes were deleted. It is as if even though the brush was deleted, something is still there to be deleted. Something that is not there is the Scene Outliner?
Replacing the Floor which is a Brush with a the Floor400x400 StaticMeshActor and resizing it seems to resolve the problem.
So it seems to be something specific to using a Brush as a floor?
Okay, so I was able to reproduce what you are seeing. I’m unsure of the cause of the issue, but it seems confined to the Top Down template in version 4.5 of the editor. This was fixed by version 4.6, so you could upgrade before you begin you project.
If you don’t want to do that, you can fix the issue in 4.5 by deleting all of the BSP meshes and both the NavMeshBoundsVolume & the RecastNavMesh. Once you add a new floor and NavMesh the navigation builds correctly.
