collision_system.hpp

//  SuperTux
//  Copyright (C) 2006 Matthias Braun <matze@braunis.de>
//                2018 Ingo Ruhnke <grumbel@gmail.com>
//
//  This program is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//
//  This program is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with this program.  If not, see <http://www.gnu.org/licenses/>.

#ifndef HEADER_SUPERTUX_COLLISION_COLLISION_SYSTEM_HPP
#define HEADER_SUPERTUX_COLLISION_COLLISION_SYSTEM_HPP

#include <vector>
#include <memory>
#include <variant>
#include <stdint.h>

#include "collision/collision.hpp"
#include "supertux/tile.hpp"
#include "math/fwd.hpp"

class CollisionObject;
class CollisionGroundMovementManager;
class DrawingContext;
class Rectf;
class Sector;

class CollisionSystem final
{
public:
  struct RaycastResult
  {
    bool is_valid; 
    std::variant<const Tile*, CollisionObject*> hit; 
    Rectf box = {}; 
  };

public:
  CollisionSystem(Sector& sector);

  void add(CollisionObject* object);
  void remove(CollisionObject* object);

  void draw(DrawingContext& context);

  void update();

  const std::shared_ptr<CollisionGroundMovementManager>& get_ground_movement_manager()
  {
    return m_ground_movement_manager;
  }

  bool is_free_of_tiles(const Rectf& rect, const bool ignoreUnisolid = false, uint32_t tiletype = Tile::SOLID) const;
  bool is_free_of_statics(const Rectf& rect, const CollisionObject* ignore_object, const bool ignoreUnisolid) const;
  bool is_free_of_movingstatics(const Rectf& rect, const CollisionObject* ignore_object) const;
  bool is_free_of_specifically_movingstatics(const Rectf& rect, const CollisionObject* ignore_object) const;


  RaycastResult get_first_line_intersection(const Vector& line_start,
                                            const Vector& line_end,
                                            bool ignore_objects,
                                            const CollisionObject* ignore_object) const;
  bool free_line_of_sight(const Vector& line_start, const Vector& line_end, bool ignore_objects, const CollisionObject* ignore_object) const;

  std::vector<CollisionObject*> get_nearby_objects(const Vector& center, float max_distance) const;

private:
  void collision_static(collision::Constraints* constraints,
                        const Vector& movement, const Rectf& dest,
                        CollisionObject& object);

  void collision_tilemap(collision::Constraints* constraints,
                         const Vector& movement, const Rectf& dest,
                         CollisionObject& object) const;

  uint32_t collision_tile_attributes(const Rectf& dest, const Vector& mov) const;

  void collision_object(CollisionObject* object1, CollisionObject* object2) const;

  void collision_static_constrains(CollisionObject& object);

  void get_hit_normal(const CollisionObject* object1, const CollisionObject* object2,
                      CollisionHit& hit, Vector& normal) const;

private:
  Sector& m_sector;

  std::vector<CollisionObject*>  m_objects;

  std::shared_ptr<CollisionGroundMovementManager> m_ground_movement_manager;

private:
  CollisionSystem(const CollisionSystem&) = delete;
  CollisionSystem& operator=(const CollisionSystem&) = delete;
};

#endif

/* EOF */