Make NavMap objects request sync only on demand

Replaces brute-force sync check loop with a self-listing system where each object is responsible for its own dirty sync, requesting it on demand only.

modules/navigation/nav_agent.cpp

@@ -32,9 +32,6 @@
 
 #include "nav_map.h"
 
-NavAgent::NavAgent() {
-}
-
 void NavAgent::set_avoidance_enabled(bool p_enabled) {
 	avoidance_enabled = p_enabled;
 	_update_rvo_agent_properties();
@@ -87,6 +84,8 @@ void NavAgent::_update_rvo_agent_properties() {
 		}
 	}
 	agent_dirty = true;
+
+	request_sync();
 }
 
 void NavAgent::set_map(NavMap *p_map) {
@@ -94,6 +93,8 @@ void NavAgent::set_map(NavMap *p_map) {
 		return;
 	}
 
+	cancel_sync_request();
+
 	if (map) {
 		map->remove_agent(this);
 	}
@@ -106,6 +107,8 @@ void NavAgent::set_map(NavMap *p_map) {
 		if (avoidance_enabled) {
 			map->set_agent_as_controlled(this);
 		}
+
+		request_sync();
 	}
 }
 
@@ -156,6 +159,8 @@ void NavAgent::set_neighbor_distance(real_t p_neighbor_distance) {
 		rvo_agent_2d.neighborDist_ = neighbor_distance;
 	}
 	agent_dirty = true;
+
+	request_sync();
 }
 
 void NavAgent::set_max_neighbors(int p_max_neighbors) {
@@ -166,6 +171,8 @@ void NavAgent::set_max_neighbors(int p_max_neighbors) {
 		rvo_agent_2d.maxNeighbors_ = max_neighbors;
 	}
 	agent_dirty = true;
+
+	request_sync();
 }
 
 void NavAgent::set_time_horizon_agents(real_t p_time_horizon) {
@@ -176,6 +183,8 @@ void NavAgent::set_time_horizon_agents(real_t p_time_horizon) {
 		rvo_agent_2d.timeHorizon_ = time_horizon_agents;
 	}
 	agent_dirty = true;
+
+	request_sync();
 }
 
 void NavAgent::set_time_horizon_obstacles(real_t p_time_horizon) {
@@ -186,6 +195,8 @@ void NavAgent::set_time_horizon_obstacles(real_t p_time_horizon) {
 		rvo_agent_2d.timeHorizonObst_ = time_horizon_obstacles;
 	}
 	agent_dirty = true;
+
+	request_sync();
 }
 
 void NavAgent::set_radius(real_t p_radius) {
@@ -196,6 +207,8 @@ void NavAgent::set_radius(real_t p_radius) {
 		rvo_agent_2d.radius_ = radius;
 	}
 	agent_dirty = true;
+
+	request_sync();
 }
 
 void NavAgent::set_height(real_t p_height) {
@@ -206,6 +219,8 @@ void NavAgent::set_height(real_t p_height) {
 		rvo_agent_2d.height_ = height;
 	}
 	agent_dirty = true;
+
+	request_sync();
 }
 
 void NavAgent::set_max_speed(real_t p_max_speed) {
@@ -218,6 +233,8 @@ void NavAgent::set_max_speed(real_t p_max_speed) {
 		}
 	}
 	agent_dirty = true;
+
+	request_sync();
 }
 
 void NavAgent::set_position(const Vector3 p_position) {
@@ -231,6 +248,8 @@ void NavAgent::set_position(const Vector3 p_position) {
 		}
 	}
 	agent_dirty = true;
+
+	request_sync();
 }
 
 void NavAgent::set_target_position(const Vector3 p_target_position) {
@@ -249,6 +268,8 @@ void NavAgent::set_velocity(const Vector3 p_velocity) {
 		}
 	}
 	agent_dirty = true;
+
+	request_sync();
 }
 
 void NavAgent::set_velocity_forced(const Vector3 p_velocity) {
@@ -265,6 +286,8 @@ void NavAgent::set_velocity_forced(const Vector3 p_velocity) {
 		}
 	}
 	agent_dirty = true;
+
+	request_sync();
 }
 
 void NavAgent::update() {
@@ -286,6 +309,8 @@ void NavAgent::set_avoidance_mask(uint32_t p_mask) {
 		rvo_agent_2d.avoidance_mask_ = avoidance_mask;
 	}
 	agent_dirty = true;
+
+	request_sync();
 }
 
 void NavAgent::set_avoidance_layers(uint32_t p_layers) {
@@ -296,6 +321,8 @@ void NavAgent::set_avoidance_layers(uint32_t p_layers) {
 		rvo_agent_2d.avoidance_layers_ = avoidance_layers;
 	}
 	agent_dirty = true;
+
+	request_sync();
 }
 
 void NavAgent::set_avoidance_priority(real_t p_priority) {
@@ -308,12 +335,16 @@ void NavAgent::set_avoidance_priority(real_t p_priority) {
 		rvo_agent_2d.avoidance_priority_ = avoidance_priority;
 	}
 	agent_dirty = true;
+
+	request_sync();
+}
+
+bool NavAgent::is_dirty() const {
+	return agent_dirty;
 }
 
-bool NavAgent::check_dirty() {
-	const bool was_dirty = agent_dirty;
+void NavAgent::sync() {
 	agent_dirty = false;
-	return was_dirty;
 }
 
 const Dictionary NavAgent::get_avoidance_data() const {
@@ -372,3 +403,23 @@ void NavAgent::set_paused(bool p_paused) {
 bool NavAgent::get_paused() const {
 	return paused;
 }
+
+void NavAgent::request_sync() {
+	if (map && !sync_dirty_request_list_element.in_list()) {
+		map->add_agent_sync_dirty_request(&sync_dirty_request_list_element);
+	}
+}
+
+void NavAgent::cancel_sync_request() {
+	if (map && sync_dirty_request_list_element.in_list()) {
+		map->remove_agent_sync_dirty_request(&sync_dirty_request_list_element);
+	}
+}
+
+NavAgent::NavAgent() :
+		sync_dirty_request_list_element(this) {
+}
+
+NavAgent::~NavAgent() {
+	cancel_sync_request();
+}

modules/navigation/nav_agent.h

@@ -35,6 +35,7 @@
 
 #include "core/object/class_db.h"
 #include "core/templates/local_vector.h"
+#include "core/templates/self_list.h"
 
 #include <Agent2d.h>
 #include <Agent3d.h>
@@ -74,8 +75,11 @@ class NavAgent : public NavRid {
 	uint32_t last_map_iteration_id = 0;
 	bool paused = false;
 
+	SelfList<NavAgent> sync_dirty_request_list_element;
+
 public:
 	NavAgent();
+	~NavAgent();
 
 	void set_avoidance_enabled(bool p_enabled);
 	bool is_avoidance_enabled() { return avoidance_enabled; }
@@ -141,7 +145,10 @@ public:
 	void set_paused(bool p_paused);
 	bool get_paused() const;
 
-	bool check_dirty();
+	bool is_dirty() const;
+	void sync();
+	void request_sync();
+	void cancel_sync_request();
 
 	// Updates this agent with rvo data after the rvo simulation avoidance step.
 	void update();

modules/navigation/nav_link.cpp

@@ -37,6 +37,8 @@ void NavLink::set_map(NavMap *p_map) {
 		return;
 	}
 
+	cancel_sync_request();
+
 	if (map) {
 		map->remove_link(this);
 	}
@@ -46,6 +48,7 @@ void NavLink::set_map(NavMap *p_map) {
 
 	if (map) {
 		map->add_link(this);
+		request_sync();
 	}
 }
 
@@ -57,6 +60,8 @@ void NavLink::set_enabled(bool p_enabled) {
 
 	// TODO: This should not require a full rebuild as the link has not really changed.
 	link_dirty = true;
+
+	request_sync();
 }
 
 void NavLink::set_bidirectional(bool p_bidirectional) {
@@ -65,6 +70,8 @@ void NavLink::set_bidirectional(bool p_bidirectional) {
 	}
 	bidirectional = p_bidirectional;
 	link_dirty = true;
+
+	request_sync();
 }
 
 void NavLink::set_start_position(const Vector3 p_position) {
@@ -73,6 +80,8 @@ void NavLink::set_start_position(const Vector3 p_position) {
 	}
 	start_position = p_position;
 	link_dirty = true;
+
+	request_sync();
 }
 
 void NavLink::set_end_position(const Vector3 p_position) {
@@ -81,11 +90,35 @@ void NavLink::set_end_position(const Vector3 p_position) {
 	}
 	end_position = p_position;
 	link_dirty = true;
+
+	request_sync();
 }
 
-bool NavLink::check_dirty() {
-	const bool was_dirty = link_dirty;
+bool NavLink::is_dirty() const {
+	return link_dirty;
+}
 
+void NavLink::sync() {
 	link_dirty = false;
-	return was_dirty;
+}
+
+void NavLink::request_sync() {
+	if (map && !sync_dirty_request_list_element.in_list()) {
+		map->add_link_sync_dirty_request(&sync_dirty_request_list_element);
+	}
+}
+
+void NavLink::cancel_sync_request() {
+	if (map && sync_dirty_request_list_element.in_list()) {
+		map->remove_link_sync_dirty_request(&sync_dirty_request_list_element);
+	}
+}
+
+NavLink::NavLink() :
+		sync_dirty_request_list_element(this) {
+	type = NavigationUtilities::PathSegmentType::PATH_SEGMENT_TYPE_LINK;
+}
+
+NavLink::~NavLink() {
+	cancel_sync_request();
 }

modules/navigation/nav_link.h

@@ -34,6 +34,8 @@
 #include "nav_base.h"
 #include "nav_utils.h"
 
+#include "core/templates/self_list.h"
+
 class NavLink : public NavBase {
 	NavMap *map = nullptr;
 	bool bidirectional = true;
@@ -43,10 +45,11 @@ class NavLink : public NavBase {
 
 	bool link_dirty = true;
 
+	SelfList<NavLink> sync_dirty_request_list_element;
+
 public:
-	NavLink() {
-		type = NavigationUtilities::PathSegmentType::PATH_SEGMENT_TYPE_LINK;
-	}
+	NavLink();
+	~NavLink();
 
 	void set_map(NavMap *p_map);
 	NavMap *get_map() const {
@@ -71,7 +74,10 @@ public:
 		return end_position;
 	}
 
-	bool check_dirty();
+	bool is_dirty() const;
+	void sync();
+	void request_sync();
+	void cancel_sync_request();
 };
 
 #endif // NAV_LINK_H

modules/navigation/nav_map.cpp

@@ -56,7 +56,7 @@ void NavMap::set_up(Vector3 p_up) {
 		return;
 	}
 	up = p_up;
-	regenerate_polygons = true;
+	map_settings_dirty = true;
 }
 
 void NavMap::set_cell_size(real_t p_cell_size) {
@@ -65,7 +65,7 @@ void NavMap::set_cell_size(real_t p_cell_size) {
 	}
 	cell_size = p_cell_size;
 	_update_merge_rasterizer_cell_dimensions();
-	regenerate_polygons = true;
+	map_settings_dirty = true;
 }
 
 void NavMap::set_cell_height(real_t p_cell_height) {
@@ -74,7 +74,7 @@ void NavMap::set_cell_height(real_t p_cell_height) {
 	}
 	cell_height = p_cell_height;
 	_update_merge_rasterizer_cell_dimensions();
-	regenerate_polygons = true;
+	map_settings_dirty = true;
 }
 
 void NavMap::set_merge_rasterizer_cell_scale(float p_value) {
@@ -83,7 +83,7 @@ void NavMap::set_merge_rasterizer_cell_scale(float p_value) {
 	}
 	merge_rasterizer_cell_scale = p_value;
 	_update_merge_rasterizer_cell_dimensions();
-	regenerate_polygons = true;
+	map_settings_dirty = true;
 }
 
 void NavMap::set_use_edge_connections(bool p_enabled) {
@@ -91,7 +91,7 @@ void NavMap::set_use_edge_connections(bool p_enabled) {
 		return;
 	}
 	use_edge_connections = p_enabled;
-	regenerate_links = true;
+	iteration_dirty = true;
 }
 
 void NavMap::set_edge_connection_margin(real_t p_edge_connection_margin) {
@@ -99,7 +99,7 @@ void NavMap::set_edge_connection_margin(real_t p_edge_connection_margin) {
 		return;
 	}
 	edge_connection_margin = p_edge_connection_margin;
-	regenerate_links = true;
+	iteration_dirty = true;
 }
 
 void NavMap::set_link_connection_radius(real_t p_link_connection_radius) {
@@ -107,7 +107,7 @@ void NavMap::set_link_connection_radius(real_t p_link_connection_radius) {
 		return;
 	}
 	link_connection_radius = p_link_connection_radius;
-	regenerate_links = true;
+	iteration_dirty = true;
 }
 
 gd::PointKey NavMap::get_point_key(const Vector3 &p_pos) const {
@@ -183,27 +183,27 @@ gd::ClosestPointQueryResult NavMap::get_closest_point_info(const Vector3 &p_poin
 
 void NavMap::add_region(NavRegion *p_region) {
 	regions.push_back(p_region);
-	regenerate_links = true;
+	iteration_dirty = true;
 }
 
 void NavMap::remove_region(NavRegion *p_region) {
 	int64_t region_index = regions.find(p_region);
 	if (region_index >= 0) {
 		regions.remove_at_unordered(region_index);
-		regenerate_links = true;
+		iteration_dirty = true;
 	}
 }
 
 void NavMap::add_link(NavLink *p_link) {
 	links.push_back(p_link);
-	regenerate_links = true;
+	iteration_dirty = true;
 }
 
 void NavMap::remove_link(NavLink *p_link) {
 	int64_t link_index = links.find(p_link);
 	if (link_index >= 0) {
 		links.remove_at_unordered(link_index);
-		regenerate_links = true;
+		iteration_dirty = true;
 	}
 }
 
@@ -361,27 +361,9 @@ void NavMap::sync() {
 	performance_data.pm_link_count = links.size();
 	performance_data.pm_obstacle_count = obstacles.size();
 
-	// Check if we need to update the links.
-	if (regenerate_polygons) {
-		for (NavRegion *region : regions) {
-			region->scratch_polygons();
-		}
-		regenerate_links = true;
-	}
+	_sync_dirty_map_update_requests();
 
-	for (NavRegion *region : regions) {
-		if (region->sync()) {
-			regenerate_links = true;
-		}
-	}
-
-	for (NavLink *link : links) {
-		if (link->check_dirty()) {
-			regenerate_links = true;
-		}
-	}
-
-	if (regenerate_links) {
+	if (iteration_dirty) {
 		performance_data.pm_polygon_count = 0;
 		performance_data.pm_edge_count = 0;
 		performance_data.pm_edge_merge_count = 0;
@@ -659,26 +641,19 @@ void NavMap::sync() {
 		iteration_id = iteration_id % UINT32_MAX + 1;
 	}
 
-	// Do we have modified obstacle positions?
-	for (NavObstacle *obstacle : obstacles) {
-		if (obstacle->check_dirty()) {
-			obstacles_dirty = true;
-		}
-	}
-	// Do we have modified agent arrays?
-	for (NavAgent *agent : agents) {
-		if (agent->check_dirty()) {
-			agents_dirty = true;
-		}
-	}
+	map_settings_dirty = false;
+	iteration_dirty = false;
+
+	_sync_avoidance();
+}
+
+void NavMap::_sync_avoidance() {
+	_sync_dirty_avoidance_update_requests();
 
-	// Update avoidance worlds.
 	if (obstacles_dirty || agents_dirty) {
 		_update_rvo_simulation();
 	}
 
-	regenerate_polygons = false;
-	regenerate_links = false;
 	obstacles_dirty = false;
 	agents_dirty = false;
 }
@@ -889,6 +864,104 @@ Vector3 NavMap::get_region_connection_pathway_end(NavRegion *p_region, int p_con
 	return Vector3();
 }
 
+void NavMap::add_region_sync_dirty_request(SelfList<NavRegion> *p_sync_request) {
+	if (p_sync_request->in_list()) {
+		return;
+	}
+	sync_dirty_requests.regions.add(p_sync_request);
+}
+
+void NavMap::add_link_sync_dirty_request(SelfList<NavLink> *p_sync_request) {
+	if (p_sync_request->in_list()) {
+		return;
+	}
+	sync_dirty_requests.links.add(p_sync_request);
+}
+
+void NavMap::add_agent_sync_dirty_request(SelfList<NavAgent> *p_sync_request) {
+	if (p_sync_request->in_list()) {
+		return;
+	}
+	sync_dirty_requests.agents.add(p_sync_request);
+}
+
+void NavMap::add_obstacle_sync_dirty_request(SelfList<NavObstacle> *p_sync_request) {
+	if (p_sync_request->in_list()) {
+		return;
+	}
+	sync_dirty_requests.obstacles.add(p_sync_request);
+}
+
+void NavMap::remove_region_sync_dirty_request(SelfList<NavRegion> *p_sync_request) {
+	if (!p_sync_request->in_list()) {
+		return;
+	}
+	sync_dirty_requests.regions.remove(p_sync_request);
+}
+
+void NavMap::remove_link_sync_dirty_request(SelfList<NavLink> *p_sync_request) {
+	if (!p_sync_request->in_list()) {
+		return;
+	}
+	sync_dirty_requests.links.remove(p_sync_request);
+}
+
+void NavMap::remove_agent_sync_dirty_request(SelfList<NavAgent> *p_sync_request) {
+	if (!p_sync_request->in_list()) {
+		return;
+	}
+	sync_dirty_requests.agents.remove(p_sync_request);
+}
+
+void NavMap::remove_obstacle_sync_dirty_request(SelfList<NavObstacle> *p_sync_request) {
+	if (!p_sync_request->in_list()) {
+		return;
+	}
+	sync_dirty_requests.obstacles.remove(p_sync_request);
+}
+
+void NavMap::_sync_dirty_map_update_requests() {
+	// If entire map settings changed make all regions dirty.
+	if (map_settings_dirty) {
+		for (NavRegion *region : regions) {
+			region->scratch_polygons();
+		}
+		iteration_dirty = true;
+	}
+
+	if (!iteration_dirty) {
+		iteration_dirty = sync_dirty_requests.regions.first() || sync_dirty_requests.links.first();
+	}
+
+	// Sync NavRegions.
+	for (SelfList<NavRegion> *element = sync_dirty_requests.regions.first(); element; element = element->next()) {
+		element->self()->sync();
+	}
+	sync_dirty_requests.regions.clear();
+
+	// Sync NavLinks.
+	for (SelfList<NavLink> *element = sync_dirty_requests.links.first(); element; element = element->next()) {
+		element->self()->sync();
+	}
+	sync_dirty_requests.links.clear();
+}
+
+void NavMap::_sync_dirty_avoidance_update_requests() {
+	// Sync NavAgents.
+	agents_dirty = sync_dirty_requests.agents.first();
+	for (SelfList<NavAgent> *element = sync_dirty_requests.agents.first(); element; element = element->next()) {
+		element->self()->sync();
+	}
+	sync_dirty_requests.agents.clear();
+
+	// Sync NavObstacles.
+	obstacles_dirty = sync_dirty_requests.obstacles.first();
+	for (SelfList<NavObstacle> *element = sync_dirty_requests.obstacles.first(); element; element = element->next()) {
+		element->self()->sync();
+	}
+	sync_dirty_requests.obstacles.clear();
+}
+
 NavMap::NavMap() {
 	avoidance_use_multiple_threads = GLOBAL_GET("navigation/avoidance/thread_model/avoidance_use_multiple_threads");
 	avoidance_use_high_priority_threads = GLOBAL_GET("navigation/avoidance/thread_model/avoidance_use_high_priority_threads");

modules/navigation/nav_map.h

@@ -72,8 +72,8 @@ class NavMap : public NavRid {
 	/// This value is used to limit how far links search to find polygons to connect to.
 	real_t link_connection_radius = NavigationDefaults3D::link_connection_radius;
 
-	bool regenerate_polygons = true;
-	bool regenerate_links = true;
+	bool map_settings_dirty = true;
+	bool iteration_dirty = true;
 
 	/// Map regions
 	LocalVector<NavRegion *> regions;
@@ -128,6 +128,13 @@ class NavMap : public NavRid {
 	HashMap<gd::EdgeKey, ConnectionPair, gd::EdgeKey> connection_pairs_map;
 	LocalVector<gd::Edge::Connection> free_edges;
 
+	struct {
+		SelfList<NavRegion>::List regions;
+		SelfList<NavLink>::List links;
+		SelfList<NavAgent>::List agents;
+		SelfList<NavObstacle>::List obstacles;
+	} sync_dirty_requests;
+
 public:
 	NavMap();
 	~NavMap();
@@ -226,12 +233,26 @@ public:
 	Vector3 get_region_connection_pathway_start(NavRegion *p_region, int p_connection_id) const;
 	Vector3 get_region_connection_pathway_end(NavRegion *p_region, int p_connection_id) const;
 
+	void add_region_sync_dirty_request(SelfList<NavRegion> *p_sync_request);
+	void add_link_sync_dirty_request(SelfList<NavLink> *p_sync_request);
+	void add_agent_sync_dirty_request(SelfList<NavAgent> *p_sync_request);
+	void add_obstacle_sync_dirty_request(SelfList<NavObstacle> *p_sync_request);
+
+	void remove_region_sync_dirty_request(SelfList<NavRegion> *p_sync_request);
+	void remove_link_sync_dirty_request(SelfList<NavLink> *p_sync_request);
+	void remove_agent_sync_dirty_request(SelfList<NavAgent> *p_sync_request);
+	void remove_obstacle_sync_dirty_request(SelfList<NavObstacle> *p_sync_request);
+
 private:
+	void _sync_dirty_map_update_requests();
+	void _sync_dirty_avoidance_update_requests();
+
 	void compute_single_step(uint32_t index, NavAgent **agent);
 
 	void compute_single_avoidance_step_2d(uint32_t index, NavAgent **agent);
 	void compute_single_avoidance_step_3d(uint32_t index, NavAgent **agent);
 
+	void _sync_avoidance();
 	void _update_rvo_simulation();
 	void _update_rvo_obstacles_tree_2d();
 	void _update_rvo_agents_tree_2d();

modules/navigation/nav_obstacle.cpp

@@ -33,10 +33,6 @@
 #include "nav_agent.h"
 #include "nav_map.h"
 
-NavObstacle::NavObstacle() {}
-
-NavObstacle::~NavObstacle() {}
-
 void NavObstacle::set_agent(NavAgent *p_agent) {
 	if (agent == p_agent) {
 		return;
@@ -45,6 +41,8 @@ void NavObstacle::set_agent(NavAgent *p_agent) {
 	agent = p_agent;
 
 	internal_update_agent();
+
+	request_sync();
 }
 
 void NavObstacle::set_avoidance_enabled(bool p_enabled) {
@@ -56,6 +54,8 @@ void NavObstacle::set_avoidance_enabled(bool p_enabled) {
 	obstacle_dirty = true;
 
 	internal_update_agent();
+
+	request_sync();
 }
 
 void NavObstacle::set_use_3d_avoidance(bool p_enabled) {
@@ -69,6 +69,8 @@ void NavObstacle::set_use_3d_avoidance(bool p_enabled) {
 	if (agent) {
 		agent->set_use_3d_avoidance(use_3d_avoidance);
 	}
+
+	request_sync();
 }
 
 void NavObstacle::set_map(NavMap *p_map) {
@@ -76,6 +78,8 @@ void NavObstacle::set_map(NavMap *p_map) {
 		return;
 	}
 
+	cancel_sync_request();
+
 	if (map) {
 		map->remove_obstacle(this);
 		if (agent) {
@@ -89,6 +93,8 @@ void NavObstacle::set_map(NavMap *p_map) {
 	if (map) {
 		map->add_obstacle(this);
 		internal_update_agent();
+
+		request_sync();
 	}
 }
 
@@ -103,6 +109,8 @@ void NavObstacle::set_position(const Vector3 p_position) {
 	if (agent) {
 		agent->set_position(position);
 	}
+
+	request_sync();
 }
 
 void NavObstacle::set_radius(real_t p_radius) {
@@ -128,6 +136,8 @@ void NavObstacle::set_height(const real_t p_height) {
 	if (agent) {
 		agent->set_height(height);
 	}
+
+	request_sync();
 }
 
 void NavObstacle::set_velocity(const Vector3 p_velocity) {
@@ -145,6 +155,8 @@ void NavObstacle::set_vertices(const Vector<Vector3> &p_vertices) {
 
 	vertices = p_vertices;
 	obstacle_dirty = true;
+
+	request_sync();
 }
 
 bool NavObstacle::is_map_changed() {
@@ -168,12 +180,16 @@ void NavObstacle::set_avoidance_layers(uint32_t p_layers) {
 	if (agent) {
 		agent->set_avoidance_layers(avoidance_layers);
 	}
+
+	request_sync();
 }
 
-bool NavObstacle::check_dirty() {
-	const bool was_dirty = obstacle_dirty;
+bool NavObstacle::is_dirty() const {
+	return obstacle_dirty;
+}
+
+void NavObstacle::sync() {
 	obstacle_dirty = false;
-	return was_dirty;
 }
 
 void NavObstacle::internal_update_agent() {
@@ -216,3 +232,23 @@ void NavObstacle::set_paused(bool p_paused) {
 bool NavObstacle::get_paused() const {
 	return paused;
 }
+
+void NavObstacle::request_sync() {
+	if (map && !sync_dirty_request_list_element.in_list()) {
+		map->add_obstacle_sync_dirty_request(&sync_dirty_request_list_element);
+	}
+}
+
+void NavObstacle::cancel_sync_request() {
+	if (map && sync_dirty_request_list_element.in_list()) {
+		map->remove_obstacle_sync_dirty_request(&sync_dirty_request_list_element);
+	}
+}
+
+NavObstacle::NavObstacle() :
+		sync_dirty_request_list_element(this) {
+}
+
+NavObstacle::~NavObstacle() {
+	cancel_sync_request();
+}

modules/navigation/nav_obstacle.h

@@ -35,6 +35,7 @@
 
 #include "core/object/class_db.h"
 #include "core/templates/local_vector.h"
+#include "core/templates/self_list.h"
 
 class NavAgent;
 class NavMap;
@@ -58,6 +59,8 @@ class NavObstacle : public NavRid {
 	uint32_t last_map_iteration_id = 0;
 	bool paused = false;
 
+	SelfList<NavObstacle> sync_dirty_request_list_element;
+
 public:
 	NavObstacle();
 	~NavObstacle();
@@ -97,7 +100,10 @@ public:
 	void set_paused(bool p_paused);
 	bool get_paused() const;
 
-	bool check_dirty();
+	bool is_dirty() const;
+	void sync();
+	void request_sync();
+	void cancel_sync_request();
 
 private:
 	void internal_update_agent();

modules/navigation/nav_region.cpp

@@ -39,6 +39,8 @@ void NavRegion::set_map(NavMap *p_map) {
 		return;
 	}
 
+	cancel_sync_request();
+
 	if (map) {
 		map->remove_region(this);
 	}
@@ -48,6 +50,7 @@ void NavRegion::set_map(NavMap *p_map) {
 
 	if (map) {
 		map->add_region(this);
+		request_sync();
 	}
 }
 
@@ -59,6 +62,8 @@ void NavRegion::set_enabled(bool p_enabled) {
 
 	// TODO: This should not require a full rebuild as the region has not really changed.
 	polygons_dirty = true;
+
+	request_sync();
 }
 
 void NavRegion::set_use_edge_connections(bool p_enabled) {
@@ -66,6 +71,8 @@ void NavRegion::set_use_edge_connections(bool p_enabled) {
 		use_edge_connections = p_enabled;
 		polygons_dirty = true;
 	}
+
+	request_sync();
 }
 
 void NavRegion::set_transform(Transform3D p_transform) {
@@ -75,6 +82,8 @@ void NavRegion::set_transform(Transform3D p_transform) {
 	transform = p_transform;
 	polygons_dirty = true;
 
+	request_sync();
+
 #ifdef DEBUG_ENABLED
 	if (map && Math::rad_to_deg(map->get_up().angle_to(transform.basis.get_column(1))) >= 90.0f) {
 		ERR_PRINT_ONCE("Attempted to update a navigation region transform rotated 90 degrees or more away from the current navigation map UP orientation.");
@@ -103,6 +112,8 @@ void NavRegion::set_navigation_mesh(Ref<NavigationMesh> p_navigation_mesh) {
 	}
 
 	polygons_dirty = true;
+
+	request_sync();
 }
 
 Vector3 NavRegion::get_closest_point_to_segment(const Vector3 &p_from, const Vector3 &p_to, bool p_use_collision) const {
@@ -220,3 +231,24 @@ void NavRegion::update_polygons() {
 
 	surface_area = _new_region_surface_area;
 }
+
+void NavRegion::request_sync() {
+	if (map && !sync_dirty_request_list_element.in_list()) {
+		map->add_region_sync_dirty_request(&sync_dirty_request_list_element);
+	}
+}
+
+void NavRegion::cancel_sync_request() {
+	if (map && sync_dirty_request_list_element.in_list()) {
+		map->remove_region_sync_dirty_request(&sync_dirty_request_list_element);
+	}
+}
+
+NavRegion::NavRegion() :
+		sync_dirty_request_list_element(this) {
+	type = NavigationUtilities::PathSegmentType::PATH_SEGMENT_TYPE_REGION;
+}
+
+NavRegion::~NavRegion() {
+	cancel_sync_request();
+}

modules/navigation/nav_region.h

@@ -57,10 +57,11 @@ class NavRegion : public NavBase {
 	Vector<Vector3> pending_navmesh_vertices;
 	Vector<Vector<int>> pending_navmesh_polygons;
 
+	SelfList<NavRegion> sync_dirty_request_list_element;
+
 public:
-	NavRegion() {
-		type = NavigationUtilities::PathSegmentType::PATH_SEGMENT_TYPE_REGION;
-	}
+	NavRegion();
+	~NavRegion();
 
 	void scratch_polygons() {
 		polygons_dirty = true;
@@ -97,6 +98,8 @@ public:
 	real_t get_surface_area() const { return surface_area; }
 
 	bool sync();
+	void request_sync();
+	void cancel_sync_request();
 
 private:
 	void update_polygons();