Using 3D gameobject prefabs with Unity Tilemap + NavMesh Surface

Required Packages

– Tested this on Unity 2023.2.3f1 (but works in other versions too)
– AI Navigation : https://docs.unity3d.com/Packages/com.unity.ai.navigation@2.0/manual/index.html
– 2D Tilemap Editor : https://docs.unity3d.com/Packages/com.unity.2d.tilemap@1.0/manual/index.html
– 2D Tilemap Extras : https://docs.unity3d.com/Packages/com.unity.2d.tilemap.extras@4.0/manual/index.html

Setup Tilemap with 3D Prefabs

– Add 2D Tilemap to Scene
– Set Grid Cell layout to XZY (so that its flat on ground)

– Create 3D Box in scene view, name it TileGrass, give it green color material, Make prefab from it (drag to Project window, some folder)
– Create 3D Box in scene view, name it TilePath, give it brown color material, Make prefab from it (drag to Project window, some folder)
– Project window: Create 2D/Tile palette/Rectangular
– Drag & Drop TileGrass and TilePath prefabs from Project window into Tile palette grid
– Select TileGrass in Tile Palette
– At Tile Palette window bottom left, select “GameObject Brush” from the dropdown (and click Toggle Brush Inspector button (top right bottom in Tile Palette window) *If they are not visible, resize tilepalette
– Assign Element 0: TileGrass prefab from Project window (do the same for TilePath)
– Now with TileGrass selected in Tile Palette window, you can paint into Scene Tilemap (select it first)
– Then toggle Paint mode in Tile Palette window top toolbar (the pencil brush button)
– You can erase painted tiles with left shift+left mouse button (or press I while mouse over some painted tile to Pick that tile as brush)

Adding NavMesh Pathfinding

– Select TileGrass prefab from Project window, add NavMesh Obstacle component to it

– Create new empty Gameobject in Scene, add NavMeshSurface component to it

– Test Baking, if road does not get over-layed with navmesh then open Window/AI/Navigation
– Make Agent radius 0.2 (so that it fits the road)

– Press Bake again in NavMeshSurface gameobject, blue area should appear over Path

Setup AI Agent

– Create new capsule gameobject in Scene (name it “Agent”)
– Place it at your tilemap path start position, can make it 0.5x smaller to fit better
– Add NavMeshAgent component to this gameobject
– Add this SampleAgent script to it https://gist.github.com/unitycoder/8e6e27faca3d40abf50c0842a51af558
– Create new empty gameobject in scene (name it “GoalGo”)
– Move it at the end of your Path
– Assign “GoalGo” gameobject into SampleAgent script in the gameobject
– Press Play
– Agent should move towards goal position, following the available path

References:
– NavMeshSurface: https://docs.unity3d.com/Packages/com.unity.ai.navigation@2.0/manual/NavMeshSurface.html
– Better 2D Navmesh (works with 2D objects instead of 3D objects) https://github.com/h8man/NavMeshPlus

Video: