/*************************************************************************/
/*  navigation_polygon.cpp                                               */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                      https://godotengine.org                          */
/*************************************************************************/
/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2022 Godot Engine contributors (cf. AUTHORS.md).   */
/*                                                                       */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the       */
/* "Software"), to deal in the Software without restriction, including   */
/* without limitation the rights to use, copy, modify, merge, publish,   */
/* distribute, sublicense, and/or sell copies of the Software, and to    */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions:                                             */
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/* The above copyright notice and this permission notice shall be        */
/* included in all copies or substantial portions of the Software.       */
/*                                                                       */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
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/*************************************************************************/

#include "navigation_polygon.h"

#include "core/core_string_names.h"
#include "core/config/engine.h"
#include "core/os/mutex.h"
#include "navigation_2d.h"
#include "scene/resources/navigation_mesh.h"
#include "scene/resources/world_2d.h"
#include "servers/navigation_2d_server.h"

#include "thirdparty/misc/triangulator.h"

#ifdef TOOLS_ENABLED
Rect2 NavigationPolygon::_edit_get_rect() const {
	if (rect_cache_dirty) {
		item_rect = Rect2();
		bool first = true;

		for (int i = 0; i < outlines.size(); i++) {
			const PoolVector<Vector2> &outline = outlines[i];
			const int outline_size = outline.size();
			if (outline_size < 3) {
				continue;
			}
			PoolVector<Vector2>::Read p = outline.read();
			for (int j = 0; j < outline_size; j++) {
				if (first) {
					item_rect = Rect2(p[j], Vector2(0, 0));
					first = false;
				} else {
					item_rect.expand_to(p[j]);
				}
			}
		}

		rect_cache_dirty = false;
	}
	return item_rect;
}

bool NavigationPolygon::_edit_is_selected_on_click(const Point2 &p_point, double p_tolerance) const {
	for (int i = 0; i < outlines.size(); i++) {
		const PoolVector<Vector2> &outline = outlines[i];
		const int outline_size = outline.size();
		if (outline_size < 3) {
			continue;
		}
		if (Geometry::is_point_in_polygon(p_point, Variant(outline))) {
			return true;
		}
	}
	return false;
}
#endif

void NavigationPolygon::set_vertices(const PoolVector<Vector2> &p_vertices) {
	{
		MutexLock lock(navmesh_generation);
		navmesh.unref();
	}
	vertices = p_vertices;
	rect_cache_dirty = true;
}

PoolVector<Vector2> NavigationPolygon::get_vertices() const {
	return vertices;
}

void NavigationPolygon::_set_polygons(const Array &p_array) {
	{
		MutexLock lock(navmesh_generation);
		navmesh.unref();
	}
	polygons.resize(p_array.size());
	for (int i = 0; i < p_array.size(); i++) {
		polygons.write[i].indices = p_array[i];
	}
}

Array NavigationPolygon::_get_polygons() const {
	Array ret;
	ret.resize(polygons.size());
	for (int i = 0; i < ret.size(); i++) {
		ret[i] = polygons[i].indices;
	}

	return ret;
}

void NavigationPolygon::_set_outlines(const Array &p_array) {
	outlines.resize(p_array.size());
	for (int i = 0; i < p_array.size(); i++) {
		outlines.write[i] = p_array[i];
	}
	rect_cache_dirty = true;
}

Array NavigationPolygon::_get_outlines() const {
	Array ret;
	ret.resize(outlines.size());
	for (int i = 0; i < ret.size(); i++) {
		ret[i] = outlines[i];
	}

	return ret;
}

void NavigationPolygon::add_polygon(const Vector<int> &p_polygon) {
	Polygon polygon;
	polygon.indices = p_polygon;
	polygons.push_back(polygon);
	{
		MutexLock lock(navmesh_generation);
		navmesh.unref();
	}
}

void NavigationPolygon::add_outline_at_index(const PoolVector<Vector2> &p_outline, int p_index) {
	outlines.insert(p_index, p_outline);
	rect_cache_dirty = true;
}

int NavigationPolygon::get_polygon_count() const {
	return polygons.size();
}

Vector<int> NavigationPolygon::get_polygon(int p_idx) {
	ERR_FAIL_INDEX_V(p_idx, polygons.size(), Vector<int>());
	return polygons[p_idx].indices;
}

void NavigationPolygon::clear_polygons() {
	polygons.clear();
	{
		MutexLock lock(navmesh_generation);
		navmesh.unref();
	}
}

Ref<NavigationMesh> NavigationPolygon::get_mesh() {
	MutexLock lock(navmesh_generation);

	if (navmesh.is_null()) {
		navmesh.instance();
		PoolVector<Vector3> verts;
		{
			verts.resize(get_vertices().size());
			PoolVector<Vector3>::Write w = verts.write();

			PoolVector<Vector2>::Read r = get_vertices().read();

			for (int i(0); i < get_vertices().size(); i++) {
				w[i] = Vector3(r[i].x, 0.0, r[i].y);
			}
		}
		navmesh->set_vertices(verts);

		for (int i(0); i < get_polygon_count(); i++) {
			navmesh->add_polygon(get_polygon(i));
		}
	}

	return navmesh;
}

void NavigationPolygon::add_outline(const PoolVector<Vector2> &p_outline) {
	outlines.push_back(p_outline);
	rect_cache_dirty = true;
}

int NavigationPolygon::get_outline_count() const {
	return outlines.size();
}

void NavigationPolygon::set_outline(int p_idx, const PoolVector<Vector2> &p_outline) {
	ERR_FAIL_INDEX(p_idx, outlines.size());
	outlines.write[p_idx] = p_outline;
	rect_cache_dirty = true;
}

void NavigationPolygon::remove_outline(int p_idx) {
	ERR_FAIL_INDEX(p_idx, outlines.size());
	outlines.remove(p_idx);
	rect_cache_dirty = true;
}

PoolVector<Vector2> NavigationPolygon::get_outline(int p_idx) const {
	ERR_FAIL_INDEX_V(p_idx, outlines.size(), PoolVector<Vector2>());
	return outlines[p_idx];
}

void NavigationPolygon::clear_outlines() {
	outlines.clear();
	rect_cache_dirty = true;
}
void NavigationPolygon::make_polygons_from_outlines() {
	{
		MutexLock lock(navmesh_generation);
		navmesh.unref();
	}
	List<TriangulatorPoly> in_poly, out_poly;

	Vector2 outside_point(-1e10, -1e10);

	for (int i = 0; i < outlines.size(); i++) {
		PoolVector<Vector2> ol = outlines[i];
		int olsize = ol.size();
		if (olsize < 3) {
			continue;
		}
		PoolVector<Vector2>::Read r = ol.read();
		for (int j = 0; j < olsize; j++) {
			outside_point.x = MAX(r[j].x, outside_point.x);
			outside_point.y = MAX(r[j].y, outside_point.y);
		}
	}

	outside_point += Vector2(0.7239784, 0.819238); //avoid precision issues

	for (int i = 0; i < outlines.size(); i++) {
		PoolVector<Vector2> ol = outlines[i];
		int olsize = ol.size();
		if (olsize < 3) {
			continue;
		}
		PoolVector<Vector2>::Read r = ol.read();

		int interscount = 0;
		//test if this is an outer outline
		for (int k = 0; k < outlines.size(); k++) {
			if (i == k) {
				continue; //no self intersect
			}

			PoolVector<Vector2> ol2 = outlines[k];
			int olsize2 = ol2.size();
			if (olsize2 < 3) {
				continue;
			}
			PoolVector<Vector2>::Read r2 = ol2.read();

			for (int l = 0; l < olsize2; l++) {
				if (Geometry::segment_intersects_segment_2d(r[0], outside_point, r2[l], r2[(l + 1) % olsize2], nullptr)) {
					interscount++;
				}
			}
		}

		bool outer = (interscount % 2) == 0;

		TriangulatorPoly tp;
		tp.Init(olsize);
		for (int j = 0; j < olsize; j++) {
			tp[j] = r[j];
		}

		if (outer) {
			tp.SetOrientation(TRIANGULATOR_CCW);
		} else {
			tp.SetOrientation(TRIANGULATOR_CW);
			tp.SetHole(true);
		}

		in_poly.push_back(tp);
	}

	TriangulatorPartition tpart;
	if (tpart.ConvexPartition_HM(&in_poly, &out_poly) == 0) { //failed!
		ERR_PRINT("NavigationPolygon: Convex partition failed! Failed to convert outlines to a valid NavigationMesh."
				  "\nNavigationPolygon outlines can not overlap vertices or edges inside same outline or with other outlines or have any intersections."
				  "\nAdd the outmost and largest outline first. To add holes inside this outline add the smaller outlines with opposite winding order.");
		return;
	}

	polygons.clear();
	vertices.resize(0);

	Map<Vector2, int> points;
	for (List<TriangulatorPoly>::Element *I = out_poly.front(); I; I = I->next()) {
		TriangulatorPoly &tp = I->get();

		struct Polygon p;

		for (int64_t i = 0; i < tp.GetNumPoints(); i++) {
			Map<Vector2, int>::Element *E = points.find(tp[i]);
			if (!E) {
				E = points.insert(tp[i], vertices.size());
				vertices.push_back(tp[i]);
			}
			p.indices.push_back(E->get());
		}

		polygons.push_back(p);
	}

	emit_signal(CoreStringNames::get_singleton()->changed);
}

void NavigationPolygon::_bind_methods() {
	ClassDB::bind_method(D_METHOD("set_vertices", "vertices"), &NavigationPolygon::set_vertices);
	ClassDB::bind_method(D_METHOD("get_vertices"), &NavigationPolygon::get_vertices);

	ClassDB::bind_method(D_METHOD("add_polygon", "polygon"), &NavigationPolygon::add_polygon);
	ClassDB::bind_method(D_METHOD("get_polygon_count"), &NavigationPolygon::get_polygon_count);
	ClassDB::bind_method(D_METHOD("get_polygon", "idx"), &NavigationPolygon::get_polygon);
	ClassDB::bind_method(D_METHOD("clear_polygons"), &NavigationPolygon::clear_polygons);
	ClassDB::bind_method(D_METHOD("get_mesh"), &NavigationPolygon::get_mesh);

	ClassDB::bind_method(D_METHOD("add_outline", "outline"), &NavigationPolygon::add_outline);
	ClassDB::bind_method(D_METHOD("add_outline_at_index", "outline", "index"), &NavigationPolygon::add_outline_at_index);
	ClassDB::bind_method(D_METHOD("get_outline_count"), &NavigationPolygon::get_outline_count);
	ClassDB::bind_method(D_METHOD("set_outline", "idx", "outline"), &NavigationPolygon::set_outline);
	ClassDB::bind_method(D_METHOD("get_outline", "idx"), &NavigationPolygon::get_outline);
	ClassDB::bind_method(D_METHOD("remove_outline", "idx"), &NavigationPolygon::remove_outline);
	ClassDB::bind_method(D_METHOD("clear_outlines"), &NavigationPolygon::clear_outlines);
	ClassDB::bind_method(D_METHOD("make_polygons_from_outlines"), &NavigationPolygon::make_polygons_from_outlines);

	ClassDB::bind_method(D_METHOD("_set_polygons", "polygons"), &NavigationPolygon::_set_polygons);
	ClassDB::bind_method(D_METHOD("_get_polygons"), &NavigationPolygon::_get_polygons);

	ClassDB::bind_method(D_METHOD("_set_outlines", "outlines"), &NavigationPolygon::_set_outlines);
	ClassDB::bind_method(D_METHOD("_get_outlines"), &NavigationPolygon::_get_outlines);

	ADD_PROPERTY(PropertyInfo(Variant::POOL_VECTOR2_ARRAY, "vertices", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NOEDITOR | PROPERTY_USAGE_INTERNAL), "set_vertices", "get_vertices");
	ADD_PROPERTY(PropertyInfo(Variant::ARRAY, "polygons", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NOEDITOR | PROPERTY_USAGE_INTERNAL), "_set_polygons", "_get_polygons");
	ADD_PROPERTY(PropertyInfo(Variant::ARRAY, "outlines", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NOEDITOR | PROPERTY_USAGE_INTERNAL), "_set_outlines", "_get_outlines");
}

NavigationPolygon::NavigationPolygon() {
	rect_cache_dirty = true;
}

NavigationPolygon::~NavigationPolygon() {
}

void NavigationPolygonInstance::set_enabled(bool p_enabled) {
	if (enabled == p_enabled) {
		return;
	}
	enabled = p_enabled;

	if (!is_inside_tree()) {
		return;
	}

	if (!enabled) {
		Navigation2DServer::get_singleton()->region_set_map(region, RID());
		Navigation2DServer::get_singleton_mut()->disconnect("map_changed", this, "_map_changed");
	} else {
		if (navigation != nullptr) {
			Navigation2DServer::get_singleton()->region_set_map(region, navigation->get_rid());
		} else {
			Navigation2DServer::get_singleton()->region_set_map(region, get_world_2d()->get_navigation_map());
		}
		Navigation2DServer::get_singleton_mut()->connect("map_changed", this, "_map_changed");
	}

	if (Engine::get_singleton()->is_editor_hint() || get_tree()->is_debugging_navigation_hint()) {
		update();
	}
}

bool NavigationPolygonInstance::is_enabled() const {
	return enabled;
}

void NavigationPolygonInstance::set_navigation_layers(uint32_t p_navigation_layers) {
	navigation_layers = p_navigation_layers;
	Navigation2DServer::get_singleton()->region_set_navigation_layers(region, navigation_layers);
}

uint32_t NavigationPolygonInstance::get_navigation_layers() const {
	return navigation_layers;
}

void NavigationPolygonInstance::set_enter_cost(real_t p_enter_cost) {
	ERR_FAIL_COND_MSG(p_enter_cost < 0.0, "The enter_cost must be positive.");
	enter_cost = MAX(p_enter_cost, 0.0);
	Navigation2DServer::get_singleton()->region_set_enter_cost(region, p_enter_cost);
}

real_t NavigationPolygonInstance::get_enter_cost() const {
	return enter_cost;
}

void NavigationPolygonInstance::set_travel_cost(real_t p_travel_cost) {
	ERR_FAIL_COND_MSG(p_travel_cost < 0.0, "The travel_cost must be positive.");
	travel_cost = MAX(p_travel_cost, 0.0);
	Navigation2DServer::get_singleton()->region_set_enter_cost(region, travel_cost);
}

real_t NavigationPolygonInstance::get_travel_cost() const {
	return travel_cost;
}

RID NavigationPolygonInstance::get_region_rid() const {
	return region;
}

/////////////////////////////
#ifdef TOOLS_ENABLED
Rect2 NavigationPolygonInstance::_edit_get_rect() const {
	return navpoly.is_valid() ? navpoly->_edit_get_rect() : Rect2();
}

bool NavigationPolygonInstance::_edit_is_selected_on_click(const Point2 &p_point, double p_tolerance) const {
	return navpoly.is_valid() ? navpoly->_edit_is_selected_on_click(p_point, p_tolerance) : false;
}
#endif

void NavigationPolygonInstance::_notification(int p_what) {
	switch (p_what) {
		case NOTIFICATION_ENTER_TREE: {
			Node2D *c = this;
			while (c) {
				navigation = Object::cast_to<Navigation2D>(c);

				if (navigation) {
					if (enabled) {
						Navigation2DServer::get_singleton()->region_set_map(region, navigation->get_rid());
					}
					break;
				}

				c = Object::cast_to<Node2D>(c->get_parent());
			}

			if (enabled && navigation == nullptr) {
				// did not find a valid navigation node parent, fallback to default navigation map on world resource
				Navigation2DServer::get_singleton()->region_set_map(region, get_world_2d()->get_navigation_map());
			}
			if (enabled) {
				Navigation2DServer::get_singleton_mut()->connect("map_changed", this, "_map_changed");
			}
		} break;
		case NOTIFICATION_TRANSFORM_CHANGED: {
			Navigation2DServer::get_singleton()->region_set_transform(region, get_global_transform());
		} break;
		case NOTIFICATION_EXIT_TREE: {
			if (navigation) {
				Navigation2DServer::get_singleton()->region_set_map(region, RID());
			}
			navigation = nullptr;

			if (enabled) {
				Navigation2DServer::get_singleton_mut()->disconnect("map_changed", this, "_map_changed");
			}
		} break;
		case NOTIFICATION_DRAW: {
			if (is_inside_tree() && (Engine::get_singleton()->is_editor_hint() || get_tree()->is_debugging_navigation_hint()) && navpoly.is_valid()) {
				PoolVector<Vector2> verts = navpoly->get_vertices();
				if (verts.size() < 3) {
					return;
				}

				Color color;
				if (enabled) {
					color = get_tree()->get_debug_navigation_color();
				} else {
					color = get_tree()->get_debug_navigation_disabled_color();
				}

				Color doors_color = color.lightened(0.2);

				RandomPCG rand;

				for (int i = 0; i < navpoly->get_polygon_count(); i++) {
					// An array of vertices for this polygon.
					Vector<int> polygon = navpoly->get_polygon(i);

					Vector<Vector2> vertices;
					vertices.resize(polygon.size());
					for (int j = 0; j < polygon.size(); j++) {
						ERR_FAIL_INDEX(polygon[j], verts.size());
						vertices.write[j] = verts[polygon[j]];
					}
					// Generate the polygon color, slightly randomly modified from the settings one.
					Color random_variation_color;
					random_variation_color.set_hsv(color.get_h() + rand.random(-1.0, 1.0) * 0.05, color.get_s(), color.get_v() + rand.random(-1.0, 1.0) * 0.1);
					random_variation_color.a = color.a;
					Vector<Color> colors;
					colors.push_back(random_variation_color);

					RS::get_singleton()->canvas_item_add_polygon(get_canvas_item(), vertices, colors);
				}

				// Draw the region
				Transform2D xform = get_global_transform();
				const Navigation2DServer *ns = Navigation2DServer::get_singleton();
				real_t radius = 1.0;
				if (navigation != nullptr) {
					radius = Navigation2DServer::get_singleton()->map_get_edge_connection_margin(navigation->get_rid());
				} else {
					radius = Navigation2DServer::get_singleton()->map_get_edge_connection_margin(get_world_2d()->get_navigation_map());
				}
				radius = radius * 0.5;
				for (int i = 0; i < ns->region_get_connections_count(region); i++) {
					// Two main points
					Vector2 a = ns->region_get_connection_pathway_start(region, i);
					a = xform.affine_inverse().xform(a);
					Vector2 b = ns->region_get_connection_pathway_end(region, i);
					b = xform.affine_inverse().xform(b);
					draw_line(a, b, doors_color);

					// Draw a circle to illustrate the margins.
					real_t angle = a.angle_to_point(b);
					draw_arc(a, radius, angle + Math_PI / 2.0, angle - Math_PI / 2.0 + Math_TAU, 10, doors_color);
					draw_arc(b, radius, angle - Math_PI / 2.0, angle + Math_PI / 2.0, 10, doors_color);
				}
			}
		} break;
	}
}

void NavigationPolygonInstance::set_navigation_polygon(const Ref<NavigationPolygon> &p_navpoly) {
	if (p_navpoly == navpoly) {
		return;
	}

	if (navpoly.is_valid()) {
		navpoly->disconnect(CoreStringNames::get_singleton()->changed, this, "_navpoly_changed");
	}

	navpoly = p_navpoly;
	Navigation2DServer::get_singleton()->region_set_navpoly(region, p_navpoly);

	if (navpoly.is_valid()) {
		navpoly->connect(CoreStringNames::get_singleton()->changed, this, "_navpoly_changed");
	}
	_navpoly_changed();

	_change_notify("navpoly");
	update_configuration_warning();
}

Ref<NavigationPolygon> NavigationPolygonInstance::get_navigation_polygon() const {
	return navpoly;
}

void NavigationPolygonInstance::_navpoly_changed() {
	if (is_inside_tree() && (Engine::get_singleton()->is_editor_hint() || get_tree()->is_debugging_navigation_hint())) {
		update();
	}
	if (navpoly.is_valid()) {
		Navigation2DServer::get_singleton()->region_set_navpoly(region, navpoly);
	}
}

void NavigationPolygonInstance::_map_changed(RID p_map) {
	if (navigation != nullptr && enabled && (navigation->get_rid() == p_map)) {
		update();
	} else if (is_inside_tree() && enabled && (get_world_2d()->get_navigation_map() == p_map)) {
		update();
	}
}

String NavigationPolygonInstance::get_configuration_warning() const {
	if (!is_visible_in_tree() || !is_inside_tree()) {
		return String();
	}

	String warning = Node2D::get_configuration_warning();
	if (!navpoly.is_valid()) {
		if (warning != String()) {
			warning += "\n\n";
		}
		warning += TTR("A NavigationPolygon resource must be set or created for this node to work. Please set a property or draw a polygon.");
	}

	return warning;
}

void NavigationPolygonInstance::_bind_methods() {
	ClassDB::bind_method(D_METHOD("set_navigation_polygon", "navpoly"), &NavigationPolygonInstance::set_navigation_polygon);
	ClassDB::bind_method(D_METHOD("get_navigation_polygon"), &NavigationPolygonInstance::get_navigation_polygon);

	ClassDB::bind_method(D_METHOD("set_enabled", "enabled"), &NavigationPolygonInstance::set_enabled);
	ClassDB::bind_method(D_METHOD("is_enabled"), &NavigationPolygonInstance::is_enabled);

	ClassDB::bind_method(D_METHOD("set_navigation_layers", "navigation_layers"), &NavigationPolygonInstance::set_navigation_layers);
	ClassDB::bind_method(D_METHOD("get_navigation_layers"), &NavigationPolygonInstance::get_navigation_layers);

	ClassDB::bind_method(D_METHOD("get_region_rid"), &NavigationPolygonInstance::get_region_rid);

	ClassDB::bind_method(D_METHOD("set_enter_cost", "enter_cost"), &NavigationPolygonInstance::set_enter_cost);
	ClassDB::bind_method(D_METHOD("get_enter_cost"), &NavigationPolygonInstance::get_enter_cost);

	ClassDB::bind_method(D_METHOD("set_travel_cost", "travel_cost"), &NavigationPolygonInstance::set_travel_cost);
	ClassDB::bind_method(D_METHOD("get_travel_cost"), &NavigationPolygonInstance::get_travel_cost);

	ClassDB::bind_method(D_METHOD("_navpoly_changed"), &NavigationPolygonInstance::_navpoly_changed);

	ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "navpoly", PROPERTY_HINT_RESOURCE_TYPE, "NavigationPolygon"), "set_navigation_polygon", "get_navigation_polygon");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "enabled"), "set_enabled", "is_enabled");
	ADD_PROPERTY(PropertyInfo(Variant::INT, "navigation_layers", PROPERTY_HINT_LAYERS_2D_NAVIGATION), "set_navigation_layers", "get_navigation_layers");
	ADD_PROPERTY(PropertyInfo(Variant::REAL, "enter_cost"), "set_enter_cost", "get_enter_cost");
	ADD_PROPERTY(PropertyInfo(Variant::REAL, "travel_cost"), "set_travel_cost", "get_travel_cost");

	ClassDB::bind_method(D_METHOD("_map_changed"), &NavigationPolygonInstance::_map_changed);
}

NavigationPolygonInstance::NavigationPolygonInstance() {
	enabled = true;
	set_notify_transform(true);
	region = Navigation2DServer::get_singleton()->region_create();

	navigation = nullptr;

	enter_cost = 0.0;
	travel_cost = 1.0;

	navigation_layers = 1;

	Navigation2DServer::get_singleton()->region_set_enter_cost(region, get_enter_cost());
	Navigation2DServer::get_singleton()->region_set_travel_cost(region, get_travel_cost());
}

NavigationPolygonInstance::~NavigationPolygonInstance() {
	Navigation2DServer::get_singleton()->free(region);
}