Fixing elevation seams

game/scenes/Levels/location_level.gd

@@ -10,6 +10,7 @@ const CHARACTER_SLOT_COUNT := 6
 @export var tile_size := 8.0
 @export var block_height := 1.0
 @export var elevation_step_height := 0.5
+@export var tile_wall_thickness := 0.08
 @export_range(1, 8, 1) var tile_radius := 3
 @export var tracked_node_path: NodePath
 @export var player_spawn_height := 2.0
@@ -292,9 +293,10 @@ func _spawn_tile(coord: Vector2i, location_data: Dictionary) -> void:
 	var biome_material := _get_biome_material(tile, biome_key)
 	if biome_material:
 		tile.material_override = biome_material
-	tile_body.add_child(tile)
-
-	tile.add_child(_create_tile_border())
+	tile_body.add_child(tile)
+	_update_tile_edge_walls(tile_root, coord, biome_material)
+
+	tile.add_child(_create_tile_border())
 	if show_tile_labels:
 		tile_root.add_child(_create_tile_label(String(location_data.get("name", ""))))
 	_update_tile_object(tile_root, location_data)
@@ -308,6 +310,11 @@ func _update_tile(coord: Vector2i, location_data: Dictionary) -> void:
 	if tile_root == null:
 		return
 	tile_root.position = _coord_to_world(coord)
+	var tile_mesh := tile_root.get_node_or_null("TileBody/TileMesh") as MeshInstance3D
+	var biome_material: Material = null
+	if tile_mesh:
+		biome_material = tile_mesh.material_override
+	_update_tile_edge_walls(tile_root, coord, biome_material)
 
 	if show_tile_labels:
 		var label := tile_root.get_node_or_null("LocationNameLabel") as Label3D
@@ -382,7 +389,7 @@ func _update_tile_inventory(tile_root: Node3D, location_data: Dictionary) -> voi
 	existing_label.text = _build_floor_inventory_label(floor_items)
 
 
-func _create_tile_border() -> MeshInstance3D:
+func _create_tile_border() -> MeshInstance3D:
 	var top_y := 0.5 + border_height_bias
 	var corners := [
 		Vector3(-0.5, top_y, -0.5),
@@ -402,8 +409,47 @@ func _create_tile_border() -> MeshInstance3D:
 
 	var border := MeshInstance3D.new()
 	border.name = "TileBorder"
-	border.mesh = border_mesh
-	return border
+	border.mesh = border_mesh
+	return border
+
+
+func _update_tile_edge_walls(tile_root: Node3D, coord: Vector2i, biome_material: Material) -> void:
+	var walls_root := tile_root.get_node_or_null("TileEdgeWalls") as Node3D
+	if walls_root == null:
+		walls_root = Node3D.new()
+		walls_root.name = "TileEdgeWalls"
+		tile_root.add_child(walls_root)
+
+	for child in walls_root.get_children():
+		child.queue_free()
+
+	var current_bottom := _get_tile_bottom_y(coord)
+	var directions := [
+		{"name": "NorthWall", "offset": Vector2i(0, -1), "position": Vector3(0.0, 0.0, -((tile_size * 0.5) - (tile_wall_thickness * 0.5))), "scale": Vector3(tile_size, 1.0, tile_wall_thickness)},
+		{"name": "SouthWall", "offset": Vector2i(0, 1), "position": Vector3(0.0, 0.0, (tile_size * 0.5) - (tile_wall_thickness * 0.5)), "scale": Vector3(tile_size, 1.0, tile_wall_thickness)},
+		{"name": "WestWall", "offset": Vector2i(-1, 0), "position": Vector3(-((tile_size * 0.5) - (tile_wall_thickness * 0.5)), 0.0, 0.0), "scale": Vector3(tile_wall_thickness, 1.0, tile_size)},
+		{"name": "EastWall", "offset": Vector2i(1, 0), "position": Vector3((tile_size * 0.5) - (tile_wall_thickness * 0.5), 0.0, 0.0), "scale": Vector3(tile_wall_thickness, 1.0, tile_size)}
+	]
+
+	for entry_variant in directions:
+		var entry := entry_variant as Dictionary
+		var neighbor_coord := coord + (entry["offset"] as Vector2i)
+		var neighbor_top := _get_neighbor_top_y(neighbor_coord)
+		if neighbor_top >= current_bottom:
+			continue
+
+		var wall_height := current_bottom - neighbor_top
+		var wall := MeshInstance3D.new()
+		wall.name = String(entry["name"])
+		var wall_mesh := BoxMesh.new()
+		wall_mesh.size = Vector3(1, 1, 1)
+		wall.mesh = wall_mesh
+		wall.scale = (entry["scale"] as Vector3) * Vector3(1.0, wall_height, 1.0)
+		var wall_position := entry["position"] as Vector3
+		wall.position = Vector3(wall_position.x, -(block_height * 0.5) - (wall_height * 0.5), wall_position.z)
+		if biome_material:
+			wall.material_override = biome_material
+		walls_root.add_child(wall)
 
 
 func _get_border_material() -> StandardMaterial3D:
@@ -491,10 +537,20 @@ func _get_tile_center_y(coord: Vector2i) -> float:
 	return (_get_tile_elevation(coord) * elevation_step_height) + (block_height * 0.5)
 
 
+func _get_tile_bottom_y(coord: Vector2i) -> float:
+	return _get_tile_elevation(coord) * elevation_step_height
+
+
 func _get_tile_surface_y(coord: Vector2i) -> float:
 	return (_get_tile_elevation(coord) * elevation_step_height) + block_height
 
 
+func _get_neighbor_top_y(coord: Vector2i) -> float:
+	if _known_locations.has(coord):
+		return _get_tile_surface_y(coord)
+	return _get_tile_bottom_y(coord)
+
+
 func _update_inventory_location_label() -> void:
 	if _inventory_location_label == null:
 		return