sand/particles.h

#ifndef PARTICLES_H
#define PARTICLES_H

#include <SDL2/SDL_events.h>
#include <SDL2/SDL_pixels.h>
#include <SDL2/SDL_render.h>
#include <SDL2/SDL_surface.h>
#include <memory>
#include <string>
#include <vector>

namespace pengine {

enum class ParticleID {
  BASIC = 0,
  SAND = 1,
  WATER = 2,
  STEAM = 3,
  LAVA = 4,
  ROCK = 5
};

class PixelColour {
public:
  union {
    struct {
      Uint8 b;
      Uint8 g;
      Uint8 r;
      Uint8 a;
    };
    Uint32 pixel;
  };
  Uint32 get_pixelcol();
  SDL_Color get_sdlcol();
  PixelColour(short r, short g, short b, short a);
  PixelColour(short r, short g, short b);
  PixelColour(const Uint8[3]);
  PixelColour(SDL_Color c);
  PixelColour(Uint32 c);
};

enum class State { SOLID, LIQUID, GAS };

struct particle_data {
  double density;
  bool liquid;
  double temperature;
  double boiling_point;
  double melting_point;
  double freezing_point;
  ParticleID gas_state;
  ParticleID liquid_state;
  ParticleID solid_state;
};

class Particle;

class Grid {
public:
  Particle **grid;
  Uint32 *pixels;
  int xsize;
  int ysize;

  Grid(int xs, int ys);
  virtual ~Grid();
  Grid &operator=(Grid o);

  void update();
  void clear();
  void update_texture();
  void add_particle_at(int x, int y, ParticleID p);
  void erase_particle_at(int x, int y);

  bool move_particle(int xa, int ya, int xb, int yb);
  int swap_particle(int xa, int ya, int xb, int yb);
  bool inside_grid(int x, int y);
  Particle *get_particle(int x, int y);
  void replace_particle(int x, int y, Particle *new_particle);
  // std::vector<Particle *> get_particles_near(int x, int y);
};

class Particle {
public:
  struct particle_data data;

  bool updated = false;
  enum ParticleID id;
  virtual void update(Grid *const, int x, int y) = 0;
  virtual PixelColour get_colour() = 0;
  Particle(ParticleID id) : id{id} {};
  virtual std::string get_name() = 0;
  virtual ~Particle() = default;
};

class BasicParticle : public Particle {
protected:
  bool update_temperature(Grid *const g, int x, int y);
  State get_state();

public:
  BasicParticle();
  BasicParticle(ParticleID id);
  struct particle_data default_data(ParticleID id);
  void update(Grid *const, int x, int y) override;
  PixelColour get_colour() override;
  std::string get_name() override;
};

class Sand : public BasicParticle {

public:
  void update(Grid *const, int x, int y) override;
  Sand() : BasicParticle(ParticleID::SAND){};
  Sand(ParticleID id) : BasicParticle(id){};
};

class Water : public BasicParticle {
public:
  void update(Grid *const, int x, int y) override;
  Water() : BasicParticle(ParticleID::WATER){};
  Water(ParticleID id) : BasicParticle(id){};
};

class Steam : public BasicParticle {
public:
  void update(Grid *const, int x, int y) override;
  Steam() : BasicParticle(ParticleID::STEAM){};
};

class Lava : public Water {
public:
  void update(Grid *const, int x, int y) override;
  Lava();
};

class Rock : public Sand {
public:
  void update(Grid *const, int x, int y) override;
  Rock();
};

} // namespace pengine
#endif