text: /*************************************************************************/
  /*  navigation_mesh.cpp                                                  */
  /*************************************************************************/
  /*                       This file is part of:                           */
  /*                           GODOT ENGINE                                */
  /*                    http://www.godotengine.org                         */
  /*************************************************************************/
  /* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
  /* Copyright (c) 2014-2017 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:                                             */
  /*                                                                       */
  /* 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  */
  /* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
  /* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
  /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
  /*************************************************************************/
  #include "navigation_mesh.h"
  #include "mesh_instance.h"
  #include "navigation.h"
  
  void NavigationMesh::create_from_mesh(const Ref<Mesh> &p_mesh) {
  
  	vertices = PoolVector<Vector3>();
  	clear_polygons();
  
  	for (int i = 0; i < p_mesh->get_surface_count(); i++) {
  
  		if (p_mesh->surface_get_primitive_type(i) != Mesh::PRIMITIVE_TRIANGLES)
  			continue;
  		Array arr = p_mesh->surface_get_arrays(i);
  		PoolVector<Vector3> varr = arr[Mesh::ARRAY_VERTEX];
  		PoolVector<int> iarr = arr[Mesh::ARRAY_INDEX];
  		if (varr.size() == 0 || iarr.size() == 0)
  			continue;
  
  		int from = vertices.size();
  		vertices.append_array(varr);
  		int rlen = iarr.size();
  		PoolVector<int>::Read r = iarr.read();
  
  		for (int j = 0; j < rlen; j += 3) {
  			Vector<int> vi;
  			vi.resize(3);
  			vi[0] = r[j + 0] + from;
  			vi[1] = r[j + 1] + from;
  			vi[2] = r[j + 2] + from;
  
  			add_polygon(vi);
  		}
  	}
  }
  
  void NavigationMesh::set_vertices(const PoolVector<Vector3> &p_vertices) {
  
  	vertices = p_vertices;
  }
  
  PoolVector<Vector3> NavigationMesh::get_vertices() const {
  
  	return vertices;
  }
  
  void NavigationMesh::_set_polygons(const Array &p_array) {
  
  	polygons.resize(p_array.size());
  	for (int i = 0; i < p_array.size(); i++) {
  		polygons[i].indices = p_array[i];
  	}
  }
  
  Array NavigationMesh::_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 NavigationMesh::add_polygon(const Vector<int> &p_polygon) {
  
  	Polygon polygon;
  	polygon.indices = p_polygon;
  	polygons.push_back(polygon);
  }
  int NavigationMesh::get_polygon_count() const {
  
  	return polygons.size();
  }
  Vector<int> NavigationMesh::get_polygon(int p_idx) {
  
  	ERR_FAIL_INDEX_V(p_idx, polygons.size(), Vector<int>());
  	return polygons[p_idx].indices;
  }
  void NavigationMesh::clear_polygons() {
  
  	polygons.clear();
  }
  
  Ref<Mesh> NavigationMesh::get_debug_mesh() {
  
  	if (debug_mesh.is_valid())
  		return debug_mesh;
  
  	PoolVector<Vector3> vertices = get_vertices();
  	PoolVector<Vector3>::Read vr = vertices.read();
  	List<Face3> faces;
  	for (int i = 0; i < get_polygon_count(); i++) {
  		Vector<int> p = get_polygon(i);
  
  		for (int j = 2; j < p.size(); j++) {
  			Face3 f;
  			f.vertex[0] = vr[p[0]];
  			f.vertex[1] = vr[p[j - 1]];
  			f.vertex[2] = vr[p[j]];
  
  			faces.push_back(f);
  		}
  	}
  
  	Map<_EdgeKey, bool> edge_map;
  	PoolVector<Vector3> tmeshfaces;
  	tmeshfaces.resize(faces.size() * 3);
  
  	{
  		PoolVector<Vector3>::Write tw = tmeshfaces.write();
  		int tidx = 0;
  
  		for (List<Face3>::Element *E = faces.front(); E; E = E->next()) {
  
  			const Face3 &f = E->get();
  
  			for (int j = 0; j < 3; j++) {
  
  				tw[tidx++] = f.vertex[j];
  				_EdgeKey ek;
  				ek.from = f.vertex[j].snapped(CMP_EPSILON);
  				ek.to = f.vertex[(j + 1) % 3].snapped(CMP_EPSILON);
  				if (ek.from < ek.to)
  					SWAP(ek.from, ek.to);
  
  				Map<_EdgeKey, bool>::Element *E = edge_map.find(ek);
  
  				if (E) {
  
  					E->get() = false;
  
  				} else {
  
  					edge_map[ek] = true;
  				}
  			}
  		}
  	}
  	List<Vector3> lines;
  
  	for (Map<_EdgeKey, bool>::Element *E = edge_map.front(); E; E = E->next()) {
  
  		if (E->get()) {
  			lines.push_back(E->key().from);
  			lines.push_back(E->key().to);
  		}
  	}
  
  	PoolVector<Vector3> varr;
  	varr.resize(lines.size());
  	{
  		PoolVector<Vector3>::Write w = varr.write();
  		int idx = 0;
  		for (List<Vector3>::Element *E = lines.front(); E; E = E->next()) {
  			w[idx++] = E->get();
  		}
  	}
  
  	debug_mesh = Ref<ArrayMesh>(memnew(ArrayMesh));
  
  	Array arr;
  	arr.resize(Mesh::ARRAY_MAX);
  	arr[Mesh::ARRAY_VERTEX] = varr;
  
  	debug_mesh->add_surface_from_arrays(Mesh::PRIMITIVE_LINES, arr);
  
  	return debug_mesh;
  }
  
  void NavigationMesh::_bind_methods() {
  
  	ClassDB::bind_method(D_METHOD("set_vertices", "vertices"), &NavigationMesh::set_vertices);
  	ClassDB::bind_method(D_METHOD("get_vertices"), &NavigationMesh::get_vertices);
  
  	ClassDB::bind_method(D_METHOD("add_polygon", "polygon"), &NavigationMesh::add_polygon);
  	ClassDB::bind_method(D_METHOD("get_polygon_count"), &NavigationMesh::get_polygon_count);
  	ClassDB::bind_method(D_METHOD("get_polygon", "idx"), &NavigationMesh::get_polygon);
  	ClassDB::bind_method(D_METHOD("clear_polygons"), &NavigationMesh::clear_polygons);
  
  	ClassDB::bind_method(D_METHOD("_set_polygons", "polygons"), &NavigationMesh::_set_polygons);
  	ClassDB::bind_method(D_METHOD("_get_polygons"), &NavigationMesh::_get_polygons);
  
  	ADD_PROPERTY(PropertyInfo(Variant::POOL_VECTOR3_ARRAY, "vertices", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NOEDITOR), "set_vertices", "get_vertices");
  	ADD_PROPERTY(PropertyInfo(Variant::ARRAY, "polygons", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NOEDITOR), "_set_polygons", "_get_polygons");
  }
  
  NavigationMesh::NavigationMesh() {
  }
  
  void NavigationMeshInstance::set_enabled(bool p_enabled) {
  
  	if (enabled == p_enabled)
  		return;
  	enabled = p_enabled;
  
  	if (!is_inside_tree())
  		return;
  
  	if (!enabled) {
  
  		if (nav_id != -1) {
  			navigation->navmesh_remove(nav_id);
  			nav_id = -1;
  		}
  	} else {
  
  		if (navigation) {
  
  			if (navmesh.is_valid()) {
  
  				nav_id = navigation->navmesh_create(navmesh, get_relative_transform(navigation), this);
  			}
  		}
  	}
  
  	if (debug_view) {
  		MeshInstance *dm = debug_view->cast_to<MeshInstance>();
  		if (is_enabled()) {
  			dm->set_material_override(get_tree()->get_debug_navigation_material());
  		} else {
  			dm->set_material_override(get_tree()->get_debug_navigation_disabled_material());
  		}
  	}
  
  	update_gizmo();
  }
  
  bool NavigationMeshInstance::is_enabled() const {
  
  	return enabled;
  }
  
  /////////////////////////////
  
  void NavigationMeshInstance::_notification(int p_what) {
  
  	switch (p_what) {
  		case NOTIFICATION_ENTER_TREE: {
  
  			Spatial *c = this;
  			while (c) {
  
  				navigation = c->cast_to<Navigation>();
  				if (navigation) {
  
  					if (enabled && navmesh.is_valid()) {
  
  						nav_id = navigation->navmesh_create(navmesh, get_relative_transform(navigation), this);
  					}
  					break;
  				}
  
  				c = c->get_parent_spatial();
  			}
  
  			if (navmesh.is_valid() && get_tree()->is_debugging_navigation_hint()) {
  
  				MeshInstance *dm = memnew(MeshInstance);
  				dm->set_mesh(navmesh->get_debug_mesh());
  				if (is_enabled()) {
  					dm->set_material_override(get_tree()->get_debug_navigation_material());
  				} else {
  					dm->set_material_override(get_tree()->get_debug_navigation_disabled_material());
  				}
  				add_child(dm);
  				debug_view = dm;
  			}
  
  		} break;
  		case NOTIFICATION_TRANSFORM_CHANGED: {
  
  			if (navigation && nav_id != -1) {
  				navigation->navmesh_set_transform(nav_id, get_relative_transform(navigation));
  			}
  
  		} break;
  		case NOTIFICATION_EXIT_TREE: {
  
  			if (navigation) {
  
  				if (nav_id != -1) {
  					navigation->navmesh_remove(nav_id);
  					nav_id = -1;
  				}
  			}
  
  			if (debug_view) {
  				debug_view->queue_delete();
  				debug_view = NULL;
  			}
  			navigation = NULL;
  		} break;
  	}
  }
  
  void NavigationMeshInstance::set_navigation_mesh(const Ref<NavigationMesh> &p_navmesh) {
  
  	if (p_navmesh == navmesh)
  		return;
  
  	if (navigation && nav_id != -1) {
  		navigation->navmesh_remove(nav_id);
  		nav_id = -1;
  	}
  	navmesh = p_navmesh;
  
  	if (navigation && navmesh.is_valid() && enabled) {
  		nav_id = navigation->navmesh_create(navmesh, get_relative_transform(navigation), this);
  	}
  
  	if (debug_view && navmesh.is_valid()) {
  		debug_view->cast_to<MeshInstance>()->set_mesh(navmesh->get_debug_mesh());
  	}
  
  	update_gizmo();
  	update_configuration_warning();
  }
  
  Ref<NavigationMesh> NavigationMeshInstance::get_navigation_mesh() const {
  
  	return navmesh;
  }
  
  String NavigationMeshInstance::get_configuration_warning() const {
  
  	if (!is_visible_in_tree() || !is_inside_tree())
  		return String();
  
  	if (!navmesh.is_valid()) {
  		return TTR("A NavigationMesh resource must be set or created for this node to work.");
  	}
  	const Spatial *c = this;
  	while (c) {
  
  		if (c->cast_to<Navigation>())
  			return String();
  
  		c = c->get_parent()->cast_to<Spatial>();
  	}
  
  	return TTR("NavigationMeshInstance must be a child or grandchild to a Navigation node. It only provides navigation data.");
  }
  
  void NavigationMeshInstance::_bind_methods() {
  
  	ClassDB::bind_method(D_METHOD("set_navigation_mesh", "navmesh"), &NavigationMeshInstance::set_navigation_mesh);
  	ClassDB::bind_method(D_METHOD("get_navigation_mesh"), &NavigationMeshInstance::get_navigation_mesh);
  
  	ClassDB::bind_method(D_METHOD("set_enabled", "enabled"), &NavigationMeshInstance::set_enabled);
  	ClassDB::bind_method(D_METHOD("is_enabled"), &NavigationMeshInstance::is_enabled);
  
  	ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "navmesh", PROPERTY_HINT_RESOURCE_TYPE, "NavigationMesh"), "set_navigation_mesh", "get_navigation_mesh");
  	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "enabled"), "set_enabled", "is_enabled");
  }
  
  NavigationMeshInstance::NavigationMeshInstance() {
  
  	debug_view = NULL;
  	navigation = NULL;
  	nav_id = -1;
  	enabled = true;
  	set_notify_transform(true);
  }
  