Merge pull request #93392 from smix8/if_you_cant_behave_responsible_you_get_locked

Fix thread-use causing navigation mesh data corruption

modules/navigation/3d/godot_navigation_server_3d.cpp

@@ -486,7 +486,7 @@ COMMAND_2(region_set_navigation_mesh, RID, p_region, Ref<NavigationMesh>, p_navi
 	NavRegion *region = region_owner.get_or_null(p_region);
 	ERR_FAIL_NULL(region);
 
-	region->set_mesh(p_navigation_mesh);
+	region->set_navigation_mesh(p_navigation_mesh);
 }
 
 #ifndef DISABLE_DEPRECATED

modules/navigation/3d/nav_mesh_generator_3d.cpp

@@ -894,6 +894,7 @@ void NavMeshGenerator3D::generator_bake_from_source_geometry_data(Ref<Navigation
 	bake_state = "Converting to native navigation mesh..."; // step #10
 
 	Vector<Vector3> nav_vertices;
+	Vector<Vector<int>> nav_polygons;
 
 	HashMap<Vector3, int> recast_vertex_to_native_index;
 	LocalVector<int> recast_index_to_native_index;
@@ -912,8 +913,6 @@ void NavMeshGenerator3D::generator_bake_from_source_geometry_data(Ref<Navigation
 			recast_index_to_native_index[i] = *existing_index_ptr;
 		}
 	}
-	p_navigation_mesh->set_vertices(nav_vertices);
-	p_navigation_mesh->clear_polygons();
 
 	for (int i = 0; i < detail_mesh->nmeshes; i++) {
 		const unsigned int *detail_mesh_m = &detail_mesh->meshes[i * 4];
@@ -933,10 +932,12 @@ void NavMeshGenerator3D::generator_bake_from_source_geometry_data(Ref<Navigation
 			nav_indices.write[1] = recast_index_to_native_index[index2];
 			nav_indices.write[2] = recast_index_to_native_index[index3];
 
-			p_navigation_mesh->add_polygon(nav_indices);
+			nav_polygons.push_back(nav_indices);
 		}
 	}
 
+	p_navigation_mesh->set_data(nav_vertices, nav_polygons);
+
 	bake_state = "Cleanup..."; // step #11
 
 	rcFreePolyMesh(poly_mesh);

modules/navigation/nav_region.cpp

@@ -74,10 +74,34 @@ void NavRegion::set_transform(Transform3D p_transform) {
 	}
 	transform = p_transform;
 	polygons_dirty = true;
+
+#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.");
+	}
+#endif // DEBUG_ENABLED
+}
+
+void NavRegion::set_navigation_mesh(Ref<NavigationMesh> p_navigation_mesh) {
+#ifdef DEBUG_ENABLED
+	if (map && !Math::is_equal_approx(double(map->get_cell_size()), double(p_navigation_mesh->get_cell_size()))) {
+		ERR_PRINT_ONCE(vformat("Attempted to update a navigation region with a navigation mesh that uses a `cell_size` of %s while assigned to a navigation map set to a `cell_size` of %s. The cell size for navigation maps can be changed by using the NavigationServer map_set_cell_size() function. The cell size for default navigation maps can also be changed in the ProjectSettings.", double(p_navigation_mesh->get_cell_size()), double(map->get_cell_size())));
+	}
+
+	if (map && !Math::is_equal_approx(double(map->get_cell_height()), double(p_navigation_mesh->get_cell_height()))) {
+		ERR_PRINT_ONCE(vformat("Attempted to update a navigation region with a navigation mesh that uses a `cell_height` of %s while assigned to a navigation map set to a `cell_height` of %s. The cell height for navigation maps can be changed by using the NavigationServer map_set_cell_height() function. The cell height for default navigation maps can also be changed in the ProjectSettings.", double(p_navigation_mesh->get_cell_height()), double(map->get_cell_height())));
+	}
+#endif // DEBUG_ENABLED
+
+	RWLockWrite write_lock(navmesh_rwlock);
+
+	pending_navmesh_vertices.clear();
+	pending_navmesh_polygons.clear();
+
+	if (p_navigation_mesh.is_valid()) {
+		p_navigation_mesh->get_data(pending_navmesh_vertices, pending_navmesh_polygons);
 	}
 
-void NavRegion::set_mesh(Ref<NavigationMesh> p_mesh) {
-	mesh = p_mesh;
 	polygons_dirty = true;
 }
 
@@ -202,33 +226,20 @@ void NavRegion::update_polygons() {
 		return;
 	}
 
-	if (mesh.is_null()) {
+	RWLockRead read_lock(navmesh_rwlock);
+
+	if (pending_navmesh_vertices.is_empty() || pending_navmesh_polygons.is_empty()) {
 		return;
 	}
 
-#ifdef DEBUG_ENABLED
-	if (!Math::is_equal_approx(double(map->get_cell_size()), double(mesh->get_cell_size()))) {
-		ERR_PRINT_ONCE(vformat("Navigation map synchronization error. Attempted to update a navigation region with a navigation mesh that uses a `cell_size` of %s while assigned to a navigation map set to a `cell_size` of %s. The cell size for navigation maps can be changed by using the NavigationServer map_set_cell_size() function. The cell size for default navigation maps can also be changed in the ProjectSettings.", double(mesh->get_cell_size()), double(map->get_cell_size())));
-	}
-
-	if (!Math::is_equal_approx(double(map->get_cell_height()), double(mesh->get_cell_height()))) {
-		ERR_PRINT_ONCE(vformat("Navigation map synchronization error. Attempted to update a navigation region with a navigation mesh that uses a `cell_height` of %s while assigned to a navigation map set to a `cell_height` of %s. The cell height for navigation maps can be changed by using the NavigationServer map_set_cell_height() function. The cell height for default navigation maps can also be changed in the ProjectSettings.", double(mesh->get_cell_height()), double(map->get_cell_height())));
-	}
-
-	if (map && Math::rad_to_deg(map->get_up().angle_to(transform.basis.get_column(1))) >= 90.0f) {
-		ERR_PRINT_ONCE("Navigation map synchronization error. Attempted to update a navigation region transform rotated 90 degrees or more away from the current navigation map UP orientation.");
-	}
-#endif // DEBUG_ENABLED
-
-	Vector<Vector3> vertices = mesh->get_vertices();
-	int len = vertices.size();
+	int len = pending_navmesh_vertices.size();
 	if (len == 0) {
 		return;
 	}
 
-	const Vector3 *vertices_r = vertices.ptr();
+	const Vector3 *vertices_r = pending_navmesh_vertices.ptr();
 
-	polygons.resize(mesh->get_polygon_count());
+	polygons.resize(pending_navmesh_polygons.size());
 
 	real_t _new_region_surface_area = 0.0;
 
@@ -238,7 +249,7 @@ void NavRegion::update_polygons() {
 		polygon.owner = this;
 		polygon.surface_area = 0.0;
 
-		Vector<int> navigation_mesh_polygon = mesh->get_polygon(navigation_mesh_polygon_index);
+		Vector<int> navigation_mesh_polygon = pending_navmesh_polygons[navigation_mesh_polygon_index];
 		navigation_mesh_polygon_index += 1;
 
 		int navigation_mesh_polygon_size = navigation_mesh_polygon.size();

modules/navigation/nav_region.h

@@ -34,12 +34,12 @@
 #include "nav_base.h"
 #include "nav_utils.h"
 
+#include "core/os/rw_lock.h"
 #include "scene/resources/navigation_mesh.h"
 
 class NavRegion : public NavBase {
 	NavMap *map = nullptr;
 	Transform3D transform;
-	Ref<NavigationMesh> mesh;
 	Vector<gd::Edge::Connection> connections;
 	bool enabled = true;
 
@@ -52,6 +52,10 @@ class NavRegion : public NavBase {
 
 	real_t surface_area = 0.0;
 
+	RWLock navmesh_rwlock;
+	Vector<Vector3> pending_navmesh_vertices;
+	Vector<Vector<int>> pending_navmesh_polygons;
+
 public:
 	NavRegion() {
 		type = NavigationUtilities::PathSegmentType::PATH_SEGMENT_TYPE_REGION;
@@ -79,10 +83,7 @@ public:
 		return transform;
 	}
 
-	void set_mesh(Ref<NavigationMesh> p_mesh);
-	const Ref<NavigationMesh> get_mesh() const {
-		return mesh;
-	}
+	void set_navigation_mesh(Ref<NavigationMesh> p_navigation_mesh);
 
 	Vector<gd::Edge::Connection> &get_connections() {
 		return connections;

scene/resources/navigation_mesh.cpp

@@ -35,10 +35,11 @@
 #endif // DEBUG_ENABLED
 
 void NavigationMesh::create_from_mesh(const Ref<Mesh> &p_mesh) {
+	RWLockWrite write_lock(rwlock);
 	ERR_FAIL_COND(p_mesh.is_null());
 
 	vertices = Vector<Vector3>();
-	clear_polygons();
+	polygons.clear();
 
 	for (int i = 0; i < p_mesh->get_surface_count(); i++) {
 		if (p_mesh->surface_get_primitive_type(i) != Mesh::PRIMITIVE_TRIANGLES) {
@@ -61,13 +62,12 @@ void NavigationMesh::create_from_mesh(const Ref<Mesh> &p_mesh) {
 		const int *r = iarr.ptr();
 
 		for (int j = 0; j < rlen; j += 3) {
-			Vector<int> vi;
-			vi.resize(3);
-			vi.write[0] = r[j + 0] + from;
-			vi.write[1] = r[j + 1] + from;
-			vi.write[2] = r[j + 2] + from;
-
-			add_polygon(vi);
+			Polygon polygon;
+			polygon.indices.resize(3);
+			polygon.indices.write[0] = r[j + 0] + from;
+			polygon.indices.write[1] = r[j + 1] + from;
+			polygon.indices.write[2] = r[j + 2] + from;
+			polygons.push_back(polygon);
 		}
 	}
 }
@@ -304,15 +304,18 @@ Vector3 NavigationMesh::get_filter_baking_aabb_offset() const {
 }
 
 void NavigationMesh::set_vertices(const Vector<Vector3> &p_vertices) {
+	RWLockWrite write_lock(rwlock);
 	vertices = p_vertices;
 	notify_property_list_changed();
 }
 
 Vector<Vector3> NavigationMesh::get_vertices() const {
+	RWLockRead read_lock(rwlock);
 	return vertices;
 }
 
 void NavigationMesh::_set_polygons(const Array &p_array) {
+	RWLockWrite write_lock(rwlock);
 	polygons.resize(p_array.size());
 	for (int i = 0; i < p_array.size(); i++) {
 		polygons.write[i].indices = p_array[i];
@@ -321,6 +324,7 @@ void NavigationMesh::_set_polygons(const Array &p_array) {
 }
 
 Array NavigationMesh::_get_polygons() const {
+	RWLockRead read_lock(rwlock);
 	Array ret;
 	ret.resize(polygons.size());
 	for (int i = 0; i < ret.size(); i++) {
@@ -331,6 +335,7 @@ Array NavigationMesh::_get_polygons() const {
 }
 
 void NavigationMesh::add_polygon(const Vector<int> &p_polygon) {
+	RWLockWrite write_lock(rwlock);
 	Polygon polygon;
 	polygon.indices = p_polygon;
 	polygons.push_back(polygon);
@@ -338,23 +343,45 @@ void NavigationMesh::add_polygon(const Vector<int> &p_polygon) {
 }
 
 int NavigationMesh::get_polygon_count() const {
+	RWLockRead read_lock(rwlock);
 	return polygons.size();
 }
 
 Vector<int> NavigationMesh::get_polygon(int p_idx) {
+	RWLockRead read_lock(rwlock);
 	ERR_FAIL_INDEX_V(p_idx, polygons.size(), Vector<int>());
 	return polygons[p_idx].indices;
 }
 
 void NavigationMesh::clear_polygons() {
+	RWLockWrite write_lock(rwlock);
 	polygons.clear();
 }
 
 void NavigationMesh::clear() {
+	RWLockWrite write_lock(rwlock);
 	polygons.clear();
 	vertices.clear();
 }
 
+void NavigationMesh::set_data(const Vector<Vector3> &p_vertices, const Vector<Vector<int>> &p_polygons) {
+	RWLockWrite write_lock(rwlock);
+	vertices = p_vertices;
+	polygons.resize(p_polygons.size());
+	for (int i = 0; i < p_polygons.size(); i++) {
+		polygons.write[i].indices = p_polygons[i];
+	}
+}
+
+void NavigationMesh::get_data(Vector<Vector3> &r_vertices, Vector<Vector<int>> &r_polygons) {
+	RWLockRead read_lock(rwlock);
+	r_vertices = vertices;
+	r_polygons.resize(polygons.size());
+	for (int i = 0; i < polygons.size(); i++) {
+		r_polygons.write[i] = polygons[i].indices;
+	}
+}
+
 #ifdef DEBUG_ENABLED
 Ref<ArrayMesh> NavigationMesh::get_debug_mesh() {
 	if (debug_mesh.is_valid()) {
@@ -372,6 +399,8 @@ Ref<ArrayMesh> NavigationMesh::get_debug_mesh() {
 		return debug_mesh;
 	}
 
+	RWLockRead read_lock(rwlock);
+
 	int polygon_count = get_polygon_count();
 
 	if (polygon_count < 1) {

scene/resources/navigation_mesh.h

@@ -31,10 +31,12 @@
 #ifndef NAVIGATION_MESH_H
 #define NAVIGATION_MESH_H
 
+#include "core/os/rw_lock.h"
 #include "scene/resources/mesh.h"
 
 class NavigationMesh : public Resource {
 	GDCLASS(NavigationMesh, Resource);
+	RWLock rwlock;
 
 	Vector<Vector3> vertices;
 	struct Polygon {
@@ -195,6 +197,9 @@ public:
 
 	void clear();
 
+	void set_data(const Vector<Vector3> &p_vertices, const Vector<Vector<int>> &p_polygons);
+	void get_data(Vector<Vector3> &r_vertices, Vector<Vector<int>> &r_polygons);
+
 #ifdef DEBUG_ENABLED
 	Ref<ArrayMesh> get_debug_mesh();
 #endif // DEBUG_ENABLED