NS-23: skip nav waypoints on NS-19 bump plateaus only

Restore obstacle routing via waypoints elsewhere; on bump tops nav often
prefers a downward segment and breaks departure. Detect plateau with
is_on_floor + flat normal + ray down into group ns19_bump; then steer
only toward authoritative goal xz. Slopes keep waypoint pathing.

client/scenes/main.tscn

@@ -138,7 +138,7 @@ transform = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, -0.95, 0.22, -1.05)
 mesh = SubResource("BoxMesh_marker")
 surface_material_override/0 = SubResource("Mat_marker_base")
 
-[node name="NS19BumpA" type="StaticBody3D" parent="World/NavigationRegion3D" unique_id=1900001 groups=["walkable"]]
+[node name="NS19BumpA" type="StaticBody3D" parent="World/NavigationRegion3D" unique_id=1900001 groups=["walkable", "ns19_bump"]]
 transform = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, -3.4, 0.075, -2.6)
 collision_layer = 1
 
@@ -149,7 +149,7 @@ surface_material_override/0 = SubResource("Mat_ns19_bump")
 [node name="CollisionShape3D" type="CollisionShape3D" parent="World/NavigationRegion3D/NS19BumpA" unique_id=1900003]
 shape = SubResource("Convex_ns19a_frustum")
 
-[node name="NS19BumpB" type="StaticBody3D" parent="World/NavigationRegion3D" unique_id=1900011 groups=["walkable"]]
+[node name="NS19BumpB" type="StaticBody3D" parent="World/NavigationRegion3D" unique_id=1900011 groups=["walkable", "ns19_bump"]]
 transform = Transform3D(1, 0, 0, 0, 1, 0, 0, 0, 1, -1.85, 0.06, -4.1)
 collision_layer = 1
 

client/scripts/player.gd

@@ -1,7 +1,7 @@
 extends CharacterBody3D
 
 ## NS-23: Nav waypoints + stored server goal for arrival.
-## NS-19: bump collision is one convex frustum (plateau + slopes); no autostep.
+## NS-19: convex frustum bumps; `ns19_bump` group — on flat plateau skip nav waypoints (departure).
 
 const MOVE_SPEED: float = 5.0
 const ARRIVE_EPS: float = 0.35
@@ -11,6 +11,8 @@ const VERT_ARRIVE_EPS: float = 0.055
 const MAX_CLIMB_SPEED: float = 2.6
 const MAX_DESCENT_SPEED: float = 2.2
 const DIRECT_APPROACH_RADIUS: float = 0.85
+## Floor normal must be this “flat” to count as bump plateau (slopes use nav waypoints).
+const NS19_BUMP_TOP_NORMAL_DOT: float = 0.992
 
 var _has_walk_goal: bool = false
 var _auth_walk_goal: Vector3 = Vector3.ZERO
@@ -41,6 +43,33 @@ func snap_to_server(world_pos: Vector3) -> void:
 	_nav_agent.set_target_position(world_pos)
 
 
+func _on_ns19_bump_plateau() -> bool:
+	if not is_on_floor():
+		return false
+	if get_floor_normal().dot(Vector3.UP) < NS19_BUMP_TOP_NORMAL_DOT:
+		return false
+	return _raycast_down_hits_group("ns19_bump", 2.5)
+
+
+func _raycast_down_hits_group(group_name: String, cast_len: float) -> bool:
+	var space: PhysicsDirectSpaceState3D = get_world_3d().direct_space_state
+	var from: Vector3 = global_position
+	var to: Vector3 = from + Vector3(0.0, -cast_len, 0.0)
+	var q: PhysicsRayQueryParameters3D = PhysicsRayQueryParameters3D.create(from, to)
+	q.collision_mask = 1
+	q.exclude = [get_rid()]
+	var hit: Dictionary = space.intersect_ray(q)
+	if hit.is_empty():
+		return false
+	var col: Variant = hit.get("collider")
+	var n: Node = col as Node
+	while n:
+		if n.is_in_group(group_name):
+			return true
+		n = n.get_parent()
+	return false
+
+
 func _steer_toward_world_point(point: Vector3) -> void:
 	var pos := global_position
 	var delta_h: Vector3 = Vector3(point.x - pos.x, 0.0, point.z - pos.z)
@@ -94,6 +123,14 @@ func _physics_process(_delta: float) -> void:
 		move_and_slide()
 		return
 
+	# Nav waypoints on the plateau often point down the slope first; goal-only + horizontal steer
+	# matches the NS-19 departure fix. Slopes stay on waypoints so obstacle routing still applies
+	# when crossing the district.
+	if _on_ns19_bump_plateau():
+		_steer_toward_world_point(_auth_walk_goal)
+		move_and_slide()
+		return
+
 	if horiz_dist <= DIRECT_APPROACH_RADIUS:
 		_steer_toward_world_point(_auth_walk_goal)
 	else: