physics_world.h

Go to the documentation of this file.

#pragma once
 
#include <box2d/box2d.h>
#include <engine/physics/creation/physics_creation_factory.h>
#include <engine/physics/world/body/body_2d.h>
#include <engine/physics/world/body/body_distance_2d.h>
#include <engine/physics/world/body/shape_type_2d.h>
#include <engine/public/util/point.h>
#include <engine/public/util/vector3.h>
 
#include <memory>
#include <set>
 
class Component;
class Collider2D;
 
constexpr int32_t default_velocity_iterations = 6;
constexpr float default_gravity_x = 0.0f;
constexpr float default_gravity_y = 30.0f;
 
class PhysicsWorld {
 public:
  PhysicsWorld();
 
  PhysicsWorld(const PhysicsWorld&) = delete;
  PhysicsWorld& operator=(const PhysicsWorld&) = delete;
  PhysicsWorld(PhysicsWorld&&) = delete;
  PhysicsWorld& operator=(PhysicsWorld&&) = delete;
 
  ~PhysicsWorld();
 
  void step(float dt);
 
  void check_collision(
      const std::vector<std::reference_wrapper<GameObject>>& objects);
 
  std::optional<std::reference_wrapper<Collider2D>> find_collider_in_objects(
      const std::vector<std::reference_wrapper<GameObject>>& objects,
      Component* comp, b2ShapeId shape_id);
 
  void check_contact_touch_begin_events(
      const std::vector<std::reference_wrapper<GameObject>>& objects);
  void check_contact_touch_end_events(
      const std::vector<std::reference_wrapper<GameObject>>& objects);
  void check_sensor_touch_begin_events(
      const std::vector<std::reference_wrapper<GameObject>>& objects);
  void check_sensor_touch_end_events(
      const std::vector<std::reference_wrapper<GameObject>>& objects);
 
  void execute_valid_collider(
      const std::vector<std::reference_wrapper<GameObject>>& objects,
      b2ShapeId a, b2ShapeId b,
      const std::function<void(Collider2D&, Collider2D&)>& callback);
 
  static BodyDistance2D distance(const Body2DTransform& a,
                                 const Body2DTransform& b);
 
  static BodyDistance2D fixture_distance(const Body2DTransform& a,
                                         const Body2DTransform& b);
 
  [[nodiscard]] b2WorldId world_id() const noexcept;
 
  [[nodiscard]] int32_t velocity_iterations() const noexcept;
  int32_t velocity_iterations(int32_t iterations) noexcept;
 
  [[nodiscard]] float gravity_x() const noexcept;
  float gravity_x(float gx) noexcept;
 
  [[nodiscard]] float gravity_y() const noexcept;
  float gravity_y(float gy) noexcept;
 
  [[nodiscard]] bool world_exists() const noexcept;
 
  static constexpr float pixels_per_meters = 16.0f;
  static constexpr float meters_per_pixels = 1.0f / pixels_per_meters;
 
 private:
  b2WorldId world_id_{};
 
  int32_t velocity_iterations_{default_velocity_iterations};
 
  float gravity_x_{default_gravity_x};
 
  float gravity_y_{default_gravity_y};
 
  bool debug_draw_enabled_{false};
};