/*************************************************************************/ /* a_star.h */ /*************************************************************************/ /* This file is part of: */ /* GODOT ENGINE */ /* https://godotengine.org */ /*************************************************************************/ /* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur. */ /* Copyright (c) 2014-2021 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. */ /*************************************************************************/ #ifndef A_STAR_H #define A_STAR_H #include "core/object/ref_counted.h" #include "core/templates/oa_hash_map.h" /** A* pathfinding algorithm @author Juan Linietsky */ class AStar : public RefCounted { GDCLASS(AStar, RefCounted); friend class AStar2D; struct Point { Point() {} int id = 0; Vector3 pos; real_t weight_scale = 0; bool enabled = false; OAHashMap neighbours = 4u; OAHashMap unlinked_neighbours = 4u; // Used for pathfinding. Point *prev_point = nullptr; real_t g_score = 0; real_t f_score = 0; uint64_t open_pass = 0; uint64_t closed_pass = 0; }; struct SortPoints { _FORCE_INLINE_ bool operator()(const Point *A, const Point *B) const { // Returns true when the Point A is worse than Point B. if (A->f_score > B->f_score) { return true; } else if (A->f_score < B->f_score) { return false; } else { return A->g_score < B->g_score; // If the f_costs are the same then prioritize the points that are further away from the start. } } }; struct Segment { union { struct { int32_t u; int32_t v; }; uint64_t key = 0; }; enum { NONE = 0, FORWARD = 1, BACKWARD = 2, BIDIRECTIONAL = FORWARD | BACKWARD }; unsigned char direction = NONE; bool operator<(const Segment &p_s) const { return key < p_s.key; } Segment() {} Segment(int p_from, int p_to) { if (p_from < p_to) { u = p_from; v = p_to; direction = FORWARD; } else { u = p_to; v = p_from; direction = BACKWARD; } } }; int last_free_id = 0; uint64_t pass = 1; OAHashMap points; Set segments; bool _solve(Point *begin_point, Point *end_point); protected: static void _bind_methods(); virtual real_t _estimate_cost(int p_from_id, int p_to_id); virtual real_t _compute_cost(int p_from_id, int p_to_id); public: int get_available_point_id() const; void add_point(int p_id, const Vector3 &p_pos, real_t p_weight_scale = 1); Vector3 get_point_position(int p_id) const; void set_point_position(int p_id, const Vector3 &p_pos); real_t get_point_weight_scale(int p_id) const; void set_point_weight_scale(int p_id, real_t p_weight_scale); void remove_point(int p_id); bool has_point(int p_id) const; Vector get_point_connections(int p_id); Array get_points(); void set_point_disabled(int p_id, bool p_disabled = true); bool is_point_disabled(int p_id) const; void connect_points(int p_id, int p_with_id, bool bidirectional = true); void disconnect_points(int p_id, int p_with_id, bool bidirectional = true); bool are_points_connected(int p_id, int p_with_id, bool bidirectional = true) const; int get_point_count() const; int get_point_capacity() const; void reserve_space(int p_num_nodes); void clear(); int get_closest_point(const Vector3 &p_point, bool p_include_disabled = false) const; Vector3 get_closest_position_in_segment(const Vector3 &p_point) const; Vector get_point_path(int p_from_id, int p_to_id); Vector get_id_path(int p_from_id, int p_to_id); AStar() {} ~AStar(); }; class AStar2D : public RefCounted { GDCLASS(AStar2D, RefCounted); AStar astar; bool _solve(AStar::Point *begin_point, AStar::Point *end_point); protected: static void _bind_methods(); virtual real_t _estimate_cost(int p_from_id, int p_to_id); virtual real_t _compute_cost(int p_from_id, int p_to_id); public: int get_available_point_id() const; void add_point(int p_id, const Vector2 &p_pos, real_t p_weight_scale = 1); Vector2 get_point_position(int p_id) const; void set_point_position(int p_id, const Vector2 &p_pos); real_t get_point_weight_scale(int p_id) const; void set_point_weight_scale(int p_id, real_t p_weight_scale); void remove_point(int p_id); bool has_point(int p_id) const; Vector get_point_connections(int p_id); Array get_points(); void set_point_disabled(int p_id, bool p_disabled = true); bool is_point_disabled(int p_id) const; void connect_points(int p_id, int p_with_id, bool p_bidirectional = true); void disconnect_points(int p_id, int p_with_id); bool are_points_connected(int p_id, int p_with_id) const; int get_point_count() const; int get_point_capacity() const; void reserve_space(int p_num_nodes); void clear(); int get_closest_point(const Vector2 &p_point, bool p_include_disabled = false) const; Vector2 get_closest_position_in_segment(const Vector2 &p_point) const; Vector get_point_path(int p_from_id, int p_to_id); Vector get_id_path(int p_from_id, int p_to_id); AStar2D() {} ~AStar2D() {} }; #endif // A_STAR_H