#ifndef VIEW_H
#define VIEW_H

#include <set>
#include <map>
#include <utility>

using namespace std;

#include "util.h"
#include "event.h"

struct visibility_state {
  unsigned int generation;
  enum { UNKNOWN, OCCLUDED, PARTIAL, FULL } visibility;
  double last;

  visibility_state () : generation(0), last(0.), visibility(UNKNOWN) { };
};

struct occ_query {
  struct view &v;
  GLuint id;
  GLuint r;

  occ_query (view &v, GLuint id, GLuint r) : v(v), id(id), r(r) { };
};

typedef event_receiver<void, occ_query> recv_occ_query;

struct view {
  sector orig;
  point p;
  vec3 d, u;
  GLfloat fov;
  GLfloat z_near, z_far, c_far;
  int w, h;

  GLfloat gamma;

  // only to be used by friends: TODO

  GLfloat nz_far, nc_far;
  GLfloat diagfact; // bounding box border to depth factor

  matrix projection;

  struct {
    plane l, r, t, b, n, f;
  } frustum;

  enum mode { DEPTH, LIGHTED } mode;
  light *l;
  set<const entity *> drawn;

  unsigned int generation;
  map<octant *, visibility_state> vismap;

  vector<octant *> vislist; // octants partially or fully visible in frustum
  vector<octant *> farlist; // octants possibly visible

  typedef pair<recv_occ_query *, GLint> oq_data;
  vector<oq_data> occ_queries;
  void begin_occ_query (recv_occ_query &recv);
  void end_occ_query ();

  void reset_projection ();

  // public
  
  void begin ();
  void pass (enum mode m);
  void end ();

  bool may_draw (const entity *e);

  view ();
  ~view ();
};

#endif