NEON-28: Dev obstacle smoke, nav reparent on hide, and docs

- Input action dev_toggle_occluder_obstacle (Ctrl+Shift+K): toggle obstacle off nav source via reparent to World, rebake NavigationRegion3D, sync NavigationAgent3D; physics/process/collision hardening unchanged intent.

- Occluder dictionary keys by instance id; related client fixes and README/project input note.

- Plan and review: PARSED_GEOMETRY_BOTH / runtime geometry removal lesson for future mechanics.

client/README.md

@@ -118,6 +118,8 @@ On **Linux** (including GitHub Actions), the path must be **`gdUnit4`** with a c
 
 **Camera zoom:** Input actions **`camera_zoom_in`** / **`camera_zoom_out`** (mouse wheel, **`=`** / **`-`**, keypad **+** / **−**) are defined in **`project.godot`**. On layouts where **`+`** requires **Shift**, remap or add a binding under **Project → Project Settings → Input Map** if needed.
 
+**Dev (NEON-28):** **`dev_toggle_occluder_obstacle`** (default **Ctrl+Shift+K**) toggles the prototype `Obstacle` visibility/collision in **`main.gd`**. **F9** / **F10** are used by the embedded debugger; use this action instead when the game is running in the editor.
+
 **Git hook (recommended):** install the repo’s local **pre-push** GDScript lint hook from the repo root:
 
 ```bash

client/project.godot

@@ -58,6 +58,11 @@ camera_zoom_out={
 , Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":-1,"window_id":0,"alt_pressed":false,"shift_pressed":false,"ctrl_pressed":false,"meta_pressed":false,"pressed":false,"keycode":4194435,"physical_keycode":4194435,"key_label":0,"unicode":0,"location":0,"echo":false,"script":null)
 ]
 }
+dev_toggle_occluder_obstacle={
+"deadzone": 0.5,
+"events": [Object(InputEventKey,"resource_local_to_scene":false,"resource_name":"","device":-1,"window_id":0,"alt_pressed":false,"shift_pressed":true,"ctrl_pressed":true,"meta_pressed":false,"pressed":false,"keycode":75,"physical_keycode":75,"key_label":0,"unicode":107,"location":0,"echo":false,"script":null)
+]
+}
 
 [physics]
 

client/scripts/ground_pick.gd

@@ -27,6 +27,10 @@ const WALL_NORMAL_DOT_CUTOFF: float = 0.09
 var fallback_camera: Camera3D
 
 
+func _ready() -> void:
+	set_process_input(true)
+
+
 func _input(event: InputEvent) -> void:
 	if event is InputEventMouseButton:
 		var mb := event as InputEventMouseButton

client/scripts/isometric_follow_camera.gd

@@ -2,8 +2,9 @@ extends Node3D
 
 ## NEON-25: client-local isometric follow; updates [CameraState] each physics tick.
 ## NEON-26: discrete zoom bands via [member zoom_band_config]; wheel / `camera_zoom_*` actions.
-## NEON-28: purge freed occluder keys from [member _occluder_overrides] before ray pass (see
+## NEON-28: occluder overrides are keyed by [method Object.get_instance_id] only — never [Object]
-## [method occluder_override_key_is_valid]).
+## keys, or [method Dictionary.keys] / [method Dictionary.erase] can freeze after an occluder is
+## [method Node.queue_free]'d (dev smoke: [InputMap] [code]dev_toggle_occluder_obstacle[/code] in [code]main.gd[/code]).
 ## Pitch / roll are fixed by presentation exports; **orbit yaw** in state stays **0** while
 ## [member allow_yaw] is false (no rotate input bound). Future orbit: read relative input here,
 ## add to `_orbit_yaw_rad`, clamp with [member max_yaw_deg].
@@ -48,7 +49,8 @@ var _smoothed_eye: Vector3 = Vector3.ZERO
 var _orbit_yaw_rad: float = 0.0
 var _zoom_band_index: int = 0
 var _warned_missing_follow_target: bool = false
-## Keys: Node3D occluder bodies. Values: Array of {mesh, surface, original} restore entries.
+## Keys: [code]int[/code] [method Object.get_instance_id] of the occluder body. Values: Array of
+## {mesh, surface, original} restore entries.
 var _occluder_overrides: Dictionary = {}
 
 @onready var camera: Camera3D = $Camera3D
@@ -251,16 +253,18 @@ func _restore_occluder_overrides_list(overrides: Array) -> void:
 		(mi as MeshInstance3D).set_surface_override_material(s, original)
 
 
-## Drop invalid keys from [member _occluder_overrides] without touching meshes.
+## Drop stale entries (freed nodes or non-int legacy keys) without touching meshes.
-## When the occluder [Node3D] is freed, its [MeshInstance3D] children and materials are gone or
-## tearing down — restoring overrides here triggers "freed instance" errors. Erasing the entry is
-## enough; live bodies stay on the valid path ([method _restore_occluder]).
 func _purge_invalid_occluder_override_keys() -> void:
-	var keys: Array = _occluder_overrides.keys()
+	var next: Dictionary = {}
-	for body in keys:
+	for k in _occluder_overrides.keys():
-		if occluder_override_key_is_valid(body):
+		if typeof(k) != TYPE_INT:
 			continue
-		_occluder_overrides.erase(body)
+		var occ_id: int = k as int
+		var node := instance_from_id(occ_id)
+		if not is_instance_valid(node) or not node is Node3D:
+			continue
+		next[occ_id] = _occluder_overrides[k]
+	_occluder_overrides = next
 
 
 ## Cast iterative rays from the smoothed eye to the player focus.
@@ -302,14 +306,25 @@ func _update_occlusion(focus: Vector3) -> void:
 			)
 		)
 
-	var to_restore: Array = _occluder_overrides.keys()
+	var blocking_ids: Dictionary = {}
-	for body in to_restore:
+	for body in newly_blocking:
-		if body not in newly_blocking:
+		if occluder_override_key_is_valid(body):
-			_restore_occluder(body)
+			blocking_ids[(body as Node3D).get_instance_id()] = true
+
+	for occ_id in _occluder_overrides.keys():
+		if typeof(occ_id) != TYPE_INT:
+			continue
+		var id: int = occ_id as int
+		if blocking_ids.has(id):
+			continue
+		_restore_occluder_id(id)
 
 	for body in newly_blocking:
-		if body not in _occluder_overrides:
+		if not occluder_override_key_is_valid(body):
-			_apply_occluder_fade(body)
+			continue
+		var bid: int = (body as Node3D).get_instance_id()
+		if not _occluder_overrides.has(bid):
+			_apply_occluder_fade(body as Node3D)
 
 
 ## Apply per-surface fade overrides to all [MeshInstance3D] children of [param body].
@@ -344,19 +359,27 @@ func _apply_occluder_fade(body: Node3D) -> void:
 			faded.albedo_color.a = policy.fade_alpha
 			mi.set_surface_override_material(s, faded)
 			overrides.append({"mesh": mi, "surface": s, "original": saved})
-	_occluder_overrides[body] = overrides
+	_occluder_overrides[body.get_instance_id()] = overrides
 
 
-## Restore saved surface override materials on [param body] and remove it from tracking.
+## Restore saved surface override materials for occluder [param occ_id] and remove it from tracking.
-func _restore_occluder(body: Node3D) -> void:
+func _restore_occluder_id(occ_id: int) -> void:
-	if not _occluder_overrides.has(body):
+	if not _occluder_overrides.has(occ_id):
 		return
-	_restore_occluder_overrides_list(_occluder_overrides[body])
+	_restore_occluder_overrides_list(_occluder_overrides[occ_id])
-	_occluder_overrides.erase(body)
+	_occluder_overrides.erase(occ_id)
 
 
 ## Restore all currently faded occluders (called on policy disable or node exit).
 func _restore_all_occluders() -> void:
 	_purge_invalid_occluder_override_keys()
-	for body in _occluder_overrides.keys():
+	for occ_id in _occluder_overrides.keys():
-		_restore_occluder(body)
+		if typeof(occ_id) == TYPE_INT:
+			_restore_occluder_id(occ_id as int)
+
+
+## Public hook for [code]dev_toggle_occluder_obstacle[/code] smoke ([code]main.gd[/code]): restore materials and clear [member _occluder_overrides] **while bodies
+## are still live**, then the caller may [method Node.queue_free] the occluder. Avoids any post-free
+## occlusion pass touching a tearing-down [StaticBody3D] (the semi-transparent faded box case).
+func restore_all_occluder_materials_now() -> void:
+	_restore_all_occluders()

client/scripts/main.gd

@@ -13,7 +13,13 @@ const MOVE_REJECT_MSG_SECONDS: float = 4.0
 ## Bump on each rejection so older one-shot timers do not clear a newer message.
 var _move_reject_msg_token: int = 0
 
+## [InputMap] [code]dev_toggle_occluder_obstacle[/code] (default **Ctrl+Shift+K**): restored when the obstacle is shown again.
+var _dev_saved_obstacle_layer: int = -1
+var _dev_saved_obstacle_mask: int = -1
+var _dev_saved_obstacle_process_mode: Node.ProcessMode = Node.PROCESS_MODE_INHERIT
+
 @onready var _camera: Camera3D = $World/IsometricFollowCamera/Camera3D
+@onready var _world: Node3D = $World
 @onready var _nav_region: NavigationRegion3D = $World/NavigationRegion3D
 @onready var _player: CharacterBody3D = $World/Player
 @onready var _ground_pick: Node3D = $GroundPick
@@ -22,9 +28,14 @@ var _move_reject_msg_token: int = 0
 @onready var _move_reject_label: Label = $UICanvas/MoveRejectLabel
 @onready var _floor: StaticBody3D = $World/NavigationRegion3D/Floor
 
+## Cached `Obstacle` body (path breaks after reparent for nav bake; do not use a fixed [NodePath]).
+var _dev_obstacle_smoke: Node3D
+
 
 func _ready() -> void:
+	set_process_unhandled_key_input(true)
 	await get_tree().process_frame
+	_dev_obstacle_smoke = get_node_or_null("World/NavigationRegion3D/Obstacle") as Node3D
 	# Runtime load + .call avoids class_name / preload static resolution issues across Godot parses.
 	load("res://scripts/random_floor_bumps.gd").call("spawn_short_random_bumps", _floor)
 	# Default `bake_navigation_mesh()` bakes on a background thread; sync bake ensures the map
@@ -69,31 +80,71 @@ func _on_move_rejected(reason_code: String) -> void:
 	)
 
 
-## Dev smoke (NEON-28 occluder purge): **F9** frees `Obstacle` while testing; remove when no longer needed.
+## Dev smoke (NEON-28 occluder): input action [code]dev_toggle_occluder_obstacle[/code] (default **Ctrl+Shift+K**)
-## After removing nav source geometry, we **rebake** — otherwise `NavigationAgent3D` keeps a stale map
+## toggles `Obstacle` **visibility + collision** — it does **not** call [method Node.queue_free].
-## and click-to-move can stop working.
+## Uses [member Node.process_mode] [code]PROCESS_MODE_DISABLED[/code] so the [StaticBody3D] is **removed
-## Coroutine is started **directly** from input (not [method call_deferred]): deferred + [code]await[/code]
+## from the physics simulation** (default [member CollisionObject3D.disable_mode] is [code]REMOVE[/code]).
-## often never resumes, so the rebake never finished and the nav map stayed stale.
+## Layer/shape tweaks alone left a **Jolt ghost collider** (invisible wall) in practice.
+## When hidden, reparents `Obstacle` under [member _world]: [NavigationMesh] source geometry scans
+## [NavigationRegion3D] children only ([code]SOURCE_GEOMETRY_ROOT_NODE_CHILDREN[/code]), and the
+## default [code]geometry_parsed_geometry_type[/code] is [code]PARSED_GEOMETRY_BOTH[/code], so a
+## child [MeshInstance3D] still carved a hole even with collision disabled — rebake alone was not enough.
+## After each toggle, rebakes (main thread) and syncs the player [NavigationAgent3D].
+## **F9** / **F10** are debugger shortcuts in the embedded game; use the Input Map action.
+## For a true **freed-node** occluder test, reload the scene or remove the body in the editor.
 func _unhandled_key_input(event: InputEvent) -> void:
-	if not event is InputEventKey:
+	if not event.is_action_pressed("dev_toggle_occluder_obstacle"):
 		return
-	var k := event as InputEventKey
+	call_deferred("_dev_toggle_obstacle_smoke_deferred")
-	if k.pressed and not k.echo and k.keycode == KEY_F9:
-		var obstacle := get_node_or_null("World/NavigationRegion3D/Obstacle")
-		if obstacle:
-			obstacle.queue_free()
-			_rebake_nav_after_obstacle_removed_async()
 
 
-func _rebake_nav_after_obstacle_removed_async() -> void:
+func _dev_toggle_obstacle_smoke_deferred() -> void:
-	await get_tree().process_frame
+	var obstacle := _dev_obstacle_smoke
+	if obstacle == null or not is_instance_valid(obstacle):
+		return
+	var rig: Node = get_node_or_null("World/IsometricFollowCamera")
+	if obstacle.visible:
+		if rig != null and rig.has_method("restore_all_occluder_materials_now"):
+			rig.call("restore_all_occluder_materials_now")
+		_dev_saved_obstacle_process_mode = obstacle.process_mode
+		var co := obstacle as CollisionObject3D
+		if co != null:
+			_dev_saved_obstacle_layer = co.collision_layer
+			_dev_saved_obstacle_mask = co.collision_mask
+			co.collision_layer = 0
+			co.collision_mask = 0
+		_dev_collision_shapes_set_disabled(obstacle, true)
+		obstacle.process_mode = Node.PROCESS_MODE_DISABLED
+		obstacle.visible = false
+		if obstacle.get_parent() == _nav_region:
+			obstacle.reparent(_world)
+	else:
+		if obstacle.get_parent() == _world:
+			obstacle.reparent(_nav_region)
+		obstacle.visible = true
+		obstacle.process_mode = _dev_saved_obstacle_process_mode
+		var co2 := obstacle as CollisionObject3D
+		if co2 != null and _dev_saved_obstacle_layer >= 0:
+			co2.collision_layer = _dev_saved_obstacle_layer
+			co2.collision_mask = _dev_saved_obstacle_mask
+		_dev_collision_shapes_set_disabled(obstacle, false)
+	call_deferred("_dev_rebake_nav_after_obstacle_toggle_deferred")
+
+
+func _dev_rebake_nav_after_obstacle_toggle_deferred() -> void:
+	if not is_instance_valid(_nav_region):
+		return
+	if _nav_region.is_baking():
+		await _nav_region.bake_finished
 	if not is_instance_valid(_nav_region):
 		return
 	_nav_region.bake_navigation_mesh(false)
-	# Let NavigationServer3D apply the rebaked mesh before repathing.
+	if is_instance_valid(_player):
-	await get_tree().physics_frame
+		_player.sync_navigation_agent_after_map_rebuild(_nav_region)
-	await get_tree().physics_frame
+
-	await get_tree().physics_frame
+
-	if not is_instance_valid(_player):
+func _dev_collision_shapes_set_disabled(root: Node, disabled: bool) -> void:
-		return
+	if root is CollisionShape3D:
-	_player.sync_navigation_agent_after_map_rebuild()
+		(root as CollisionShape3D).disabled = disabled
+	for c in root.get_children():
+		_dev_collision_shapes_set_disabled(c, disabled)

client/scripts/player.gd

@@ -90,7 +90,16 @@ func clear_nav_goal() -> void:
 
 
 ## Repath on a new nav map (e.g. after [NavigationRegion3D] rebake when geometry is removed).
-func sync_navigation_agent_after_map_rebuild() -> void:
+## Rebaking can leave [NavigationAgent3D] on a stale map RID; rebind to the world's map first.
+func sync_navigation_agent_after_map_rebuild(nav_region: NavigationRegion3D) -> void:
+	var map_rid: RID = RID()
+	var w3d := get_world_3d()
+	if w3d != null:
+		map_rid = w3d.navigation_map
+	if map_rid == RID() and is_instance_valid(nav_region):
+		map_rid = NavigationServer3D.region_get_map(nav_region.get_region_rid())
+	if map_rid != RID():
+		_nav_agent.set_navigation_map(map_rid)
 	if _has_walk_goal:
 		_nav_agent.set_target_position(_auth_walk_goal)
 	else:

client/scripts/position_authority_client.gd

@@ -18,6 +18,9 @@ var _http: Node
 var _busy: bool = false
 var _phase: Phase = Phase.BOOT_GET
 
+## Latest click target while [_busy] (POST or VERIFY in flight); coalesced so clicks are not lost.
+var _pending_move_target: Variant = null
+
 
 func _create_http_request() -> Node:
 	return HTTPRequest.new()
@@ -26,6 +29,8 @@ func _create_http_request() -> Node:
 func _ready() -> void:
 	_http = _create_http_request()
 	add_child(_http)
+	if _http is HTTPRequest:
+		(_http as HTTPRequest).timeout = 30.0
 	@warning_ignore("unsafe_method_access")
 	_http.request_completed.connect(_on_request_completed)
 
@@ -40,7 +45,22 @@ func sync_from_server() -> void:
 
 func submit_move_target(world: Vector3) -> void:
 	if _busy:
+		_pending_move_target = world
 		return
+	_pending_move_target = null
+	_start_move_post(world)
+
+
+func _try_flush_pending_move() -> void:
+	if _busy:
+		return
+	if _pending_move_target is Vector3:
+		var w: Vector3 = _pending_move_target as Vector3
+		_pending_move_target = null
+		_start_move_post(w)
+
+
+func _start_move_post(world: Vector3) -> void:
 	_busy = true
 	_phase = Phase.POST_MOVE
 	var url := "%s/game/players/%s/move" % [_base_root(), _player_path_segment()]
@@ -54,6 +74,7 @@ func submit_move_target(world: Vector3) -> void:
 	if err != OK:
 		push_warning("PositionAuthorityClient: POST failed to start (%s)" % err)
 		_busy = false
+		_try_flush_pending_move()
 
 
 func _base_root() -> String:
@@ -71,13 +92,18 @@ func _request_get() -> void:
 	if err != OK:
 		push_warning("PositionAuthorityClient: GET failed to start (%s)" % err)
 		_busy = false
+		_try_flush_pending_move()
 
 
 func _on_request_completed(
 	_result: int, response_code: int, _headers: PackedStringArray, body: PackedByteArray
 ) -> void:
 	if _result != HTTPRequest.RESULT_SUCCESS:
+		push_warning(
+			"PositionAuthorityClient: HTTP failed (result=%s); releasing busy." % _result
+		)
 		_busy = false
+		_try_flush_pending_move()
 		return
 
 	var text := body.get_string_from_utf8()
@@ -87,16 +113,19 @@ func _on_request_completed(
 			_busy = false
 			if response_code == 200:
 				_emit_position_from_response(text, true)
+			_try_flush_pending_move()
 		Phase.POST_MOVE:
 			if response_code == 400:
 				_emit_move_rejection_if_present(text)
 				_busy = false
+				_try_flush_pending_move()
 				return
 			if response_code != 200:
 				push_warning(
 					"PositionAuthorityClient: move POST unexpected code %s" % response_code
 				)
 				_busy = false
+				_try_flush_pending_move()
 				return
 			_phase = Phase.VERIFY_GET
 			_request_get()
@@ -104,6 +133,11 @@ func _on_request_completed(
 			_busy = false
 			if response_code == 200:
 				_emit_position_from_response(text, false)
+			else:
+				push_warning(
+					"PositionAuthorityClient: VERIFY GET unexpected code %s" % response_code
+				)
+			_try_flush_pending_move()
 
 
 func _emit_move_rejection_if_present(json_text: String) -> void:
@@ -124,12 +158,15 @@ func _emit_move_rejection_if_present(json_text: String) -> void:
 func _emit_position_from_response(json_text: String, apply_as_snap: bool) -> void:
 	var parsed: Variant = JSON.parse_string(json_text)
 	if parsed == null:
+		push_warning("PositionAuthorityClient: position response JSON parse failed")
 		return
 	if not parsed is Dictionary:
+		push_warning("PositionAuthorityClient: position response is not a JSON object")
 		return
 	var data: Dictionary = parsed
 	var pos_variant: Variant = data.get("position", null)
 	if not pos_variant is Dictionary:
+		push_warning("PositionAuthorityClient: position response missing `position` object")
 		return
 	var pos: Dictionary = pos_variant
 	var x: float = float(pos.get("x", 0.0))

docs/plans/NEON-28-implementation-plan.md

@@ -79,6 +79,11 @@ Jira acceptance criteria (verbatim intent):
 | **Invalid occluder keys** | **Erase only** | Freed body ⇒ subtree is gone; restoring overrides hits freed `MeshInstance3D` / materials. Drop dict entry; live bodies restore when they leave the ray. |
 | **Epic Slice 2 wording** | **Align with rotation policy** | Satisfies Jira AC on “yaw not exposed / default in UX” vs misleading “no rotation.” |
 | **Rig tick (jitter follow-up)** | **`_physics_process` + `process_physics_priority = 1`** | `Player` default **0** runs before **1**; camera reads post–`move_and_slide`. Avoids `_process` vs 120 Hz physics jitter (camera was above `Player` in scene order). |
+| **Runtime “remove obstacle” + `NavigationAgent3D`** | **Reparent out of `NavigationRegion3D`, then rebake + sync agent** | Default `NavigationMesh.geometry_parsed_geometry_type` is **`PARSED_GEOMETRY_BOTH`**: **mesh instances** under the region are baked as source geometry alongside static colliders. Disabling collision (or rebaking alone) does **not** reopen nav if the body’s **`MeshInstance3D` remains a child of the region** — the hole persists. For any **gameplay mechanic that removes or opens geometry** while using baked nav, either **exclude that mesh from source** (project/settings), **reparent** the subtree **outside** the region before rebake, **`queue_free`** (if safe), or switch to an explicit geometry pipeline. Prototype dev toggle: `main.gd` reparents `Obstacle` to `World` when hidden, rebakes, `player.sync_navigation_agent_after_map_rebuild`. |
+
+### Runtime navigation (lesson for future mechanics)
+
+If the client uses **`NavigationRegion3D`** with default parsing (**colliders + meshes**), **hiding** or **disabling collision** on a prop is **not** enough for **click-to-move** to cross that tile: **`bake_navigation_mesh`** will still see **`MeshInstance3D`** children of the region. **Rebake + `NavigationAgent3D` map sync** only fixes the path once that geometry is **no longer under the region** (or no longer parsed). Plan any **destructible door**, **removed barricade**, or **temporary wall** with this in mind — same pitfall as NEON-28 dev smoke.
 
 ## Files to add
 
@@ -106,7 +111,7 @@ Jira acceptance criteria (verbatim intent):
 
 **Manual verification:** Main scene — zoom bands, occlusion fade, fixed yaw UX; spot-check Slice 2 behaviors (readable motion, occlusion active).
 
-**Freed occluder (end-to-end, editor):** Position player so `Obstacle` is between camera and player (fade active), then `queue_free` the occluder. Expect **no** recurring script errors and **no** stuck transparent materials on other meshes. **`Obstacle` lives under `NavigationRegion3D`** — after removing it, **rebake** the nav mesh (see **`main.gd` F9**: `await` a frame after `queue_free`, then `bake_navigation_mesh(false)`, then a few physics frames, then **`Player.sync_navigation_agent_after_map_rebuild()`**) or click-to-move can stop. Do **not** drive that sequence with **`call_deferred` + `await`** on the same method — the coroutine may never resume. Complements static `occluder_override_key_is_valid` tests, which do not execute the full purge path in CI.
+**Occluder smoke (embedded editor):** Input action **`dev_toggle_occluder_obstacle`** (default **Ctrl+Shift+K** in `project.godot`) toggles `Obstacle` visibility + collision in `main.gd` (does not `queue_free`). **F9** / **F10** are debugger shortcuts (**Suspend/Resume**, **next frame**) when the embedded game has focus. Position the player so the obstacle is on the occlusion ray to test fade + `restore_all_occluder_materials_now` before hide. After hide, confirm **click-to-move through the former cell**: the implementation **reparents** the obstacle under **`World`**, **rebakes** the region mesh, and **`sync_navigation_agent_after_map_rebuild`** — see **Decisions** table and **Runtime navigation** note (**`PARSED_GEOMETRY_BOTH`**). Complements static `occluder_override_key_is_valid` tests, which do not execute the full purge path in CI.
 
 ## Open questions / risks
 
@@ -118,3 +123,4 @@ Jira acceptance criteria (verbatim intent):
 - `camera_state.gd` consumer contract header; `isometric_follow_camera.gd` invalid occluder purge + `occluder_override_key_is_valid`; tests in `isometric_follow_camera_test.gd`.
 - Docs: `E1_M2_IsometricCameraController.md` (Ready, consumer contract, NEON-28 snapshot), `E6_M2_ConsentAndRiskUxSignals.md` (E1.M2 adjacency), `module_dependency_register.md`, `documentation_and_implementation_alignment.md`, `epic_01_core_player_runtime.md` Slice 2.
 - Follow-up: rig **`_physics_process`** + priority (see **Decisions**).
+- Client dev smoke (`main.gd`): obstacle toggle + **nav**: reparent out of `NavigationRegion3D`, rebake, agent sync — documents the **`PARSED_GEOMETRY_BOTH`** / mesh-as-source pitfall for future **runtime geometry removal** (see **Decisions** and **Runtime navigation**).

docs/reviews/2026-04-10-NEON-28.md

@@ -16,7 +16,7 @@ This branch closes the E1.M2 prototype slice in a coherent way: `CameraState` is
 
 | Document | Assessment |
 |----------|------------|
-| `docs/plans/NEON-28-implementation-plan.md` | **Matches** — Scope, decisions, shipped notes, acceptance checklist, and Technical approach (`_physics_process` + priority) align with the branch. |
+| `docs/plans/NEON-28-implementation-plan.md` | **Matches** — Scope, decisions, shipped notes, acceptance checklist, and Technical approach (`_physics_process` + priority) align with the branch. **Supplement:** plan now records **runtime nav mesh** behavior (`PARSED_GEOMETRY_BOTH`, reparent + rebake for dev smoke); see plan **Decisions** and **Runtime navigation (lesson for future mechanics)**. |
 | `docs/decomposition/modules/E1_M2_IsometricCameraController.md` | **Matches** — Consumer contract, E1.M2 Ready status, yaw semantics, occlusion hardening, and the `_physics_process` update all reflect the implementation. |
 | `docs/decomposition/modules/E6_M2_ConsentAndRiskUxSignals.md` | **Matches** — Camera-adjacent consumer guidance and authority split are consistent with the code and E1.M2 doc. |
 | `docs/decomposition/modules/module_dependency_register.md` | **Matches** — E1.M2 is marked Ready with appropriate script/scene pointers. |
@@ -45,6 +45,14 @@ _None identified in the implementation reviewed._
 - Godot / GdUnit client tests were not run in this session.
 - Before merge, I would still run: `dotnet build NeonSprawl.sln` with the dev server stopped, then the documented camera manual checks in `client/README.md` plus the NEON-28 plan step that frees an occluder while it is faded.
 
+## Supplement — runtime navigation (2026-04-10)
+
+**Context:** Dev smoke for the prototype `Obstacle` must match **click-to-move**, not only physics and occlusion.
+
+**Lesson:** With Godot’s default **`NavigationMesh.geometry_parsed_geometry_type`** (**`PARSED_GEOMETRY_BOTH`**), **`MeshInstance3D` nodes under `NavigationRegion3D`** still contribute to bakes. **Disabling collision and rebaking** can leave the **nav hole** unchanged. **`main.gd`** fixes dev smoke by **reparenting** the obstacle **out of the region**, **rebaking**, and **`sync_navigation_agent_after_map_rebuild`**.
+
+**Product impact:** Any future mechanic that **removes or opens world geometry** during play (barricades, doors, destroyed cover) must account for **nav source geometry**, not just **collision** — see `docs/plans/NEON-28-implementation-plan.md` (**Decisions** table row and **Runtime navigation** subsection).
+
 ---
 
 *Review produced per [code review agent](.cursor/rules/code-review-agent.md).*