// the interface the game uses to access the engine

extern int curtime;                     // current frame time
extern int lastmillis;                  // last time
extern int elapsedtime;                 // elapsed frame time
extern int totalmillis;                 // total elapsed time
extern int gamespeed, paused;

extern void lightent(extentity &e, float height = 8.0f);
extern void lightreaching(const vec &target, vec &color, vec &dir, bool fast = false, extentity *e = 0, float minambient = 0.4f);

enum { RAY_BB = 1, RAY_POLY = 3, RAY_ALPHAPOLY = 7, RAY_ENTS = 9, RAY_CLIPMAT = 16, RAY_SKIPFIRST = 32, RAY_EDITMAT = 64, RAY_SHADOW = 128, RAY_PASS = 256, RAY_SKIPSKY = 512 };

extern float raycube   (const vec &o, const vec &ray,     float radius = 0, int mode = RAY_CLIPMAT, int size = 0, extentity *t = 0);
extern float raycubepos(const vec &o, const vec &ray, vec &hit, float radius = 0, int mode = RAY_CLIPMAT, int size = 0);
extern float rayfloor  (const vec &o, vec &floor, int mode = 0, float radius = 0);
extern bool  raycubelos(const vec &o, const vec &dest, vec &hitpos);

extern int thirdperson;
extern bool isthirdperson();

// command
extern int variable(const char *name, int min, int cur, int max, int *storage, identfun fun, int flags);
extern float fvariable(const char *name, float min, float cur, float max, float *storage, identfun fun, int flags);
extern char *svariable(const char *name, const char *cur, char **storage, identfun fun, int flags);
extern void setvar(const char *name, int i, bool dofunc = true, bool doclamp = true);
extern void setfvar(const char *name, float f, bool dofunc = true, bool doclamp = true);
extern void setsvar(const char *name, const char *str, bool dofunc = true);
extern void setvarchecked(ident *id, int val);
extern void setfvarchecked(ident *id, float val);
extern void setsvarchecked(ident *id, const char *val);
extern void touchvar(const char *name);
extern int getvar(const char *name);
extern int getvarmin(const char *name);
extern int getvarmax(const char *name);
extern bool identexists(const char *name);
extern ident *getident(const char *name);
extern ident *newident(const char *name, int flags = 0);
extern ident *readident(const char *name);
extern ident *writeident(const char *name, int flags = 0);
extern bool addcommand(const char *name, identfun fun, const char *narg, int type = ID_COMMAND);
extern uint *compilecode(const char *p);
extern void keepcode(uint *p);
extern void freecode(uint *p);
extern void executeret(const uint *code, tagval &result = *commandret);
extern void executeret(const char *p, tagval &result = *commandret);
extern void executeret(ident *id, tagval *args, int numargs, bool lookup = false, tagval &result = *commandret);
extern char *executestr(const uint *code);
extern char *executestr(const char *p);
extern char *executestr(ident *id, tagval *args, int numargs, bool lookup = false);
extern char *execidentstr(const char *name, bool lookup = false);
extern int execute(const uint *code);
extern int execute(const char *p);
extern int execute(ident *id, tagval *args, int numargs, bool lookup = false);
extern int execident(const char *name, int noid = 0, bool lookup = false);
extern float executefloat(const uint *code);
extern float executefloat(const char *p);
extern float executefloat(ident *id, tagval *args, int numargs, bool lookup = false);
extern float execidentfloat(const char *name, float noid = 0, bool lookup = false);
extern bool executebool(const uint *code);
extern bool executebool(const char *p);
extern bool executebool(ident *id, tagval *args, int numargs, bool lookup = false);
extern bool execidentbool(const char *name, bool noid = false, bool lookup = false);
extern bool execfile(const char *cfgfile, bool msg = true);
extern void alias(const char *name, const char *action);
extern void alias(const char *name, tagval &v);
extern const char *getalias(const char *name);
extern const char *escapestring(const char *s);
extern const char *escapeid(const char *s);
static inline const char *escapeid(ident &id) { return escapeid(id.name); }
extern bool validateblock(const char *s);
extern void explodelist(const char *s, vector<char *> &elems, int limit = -1);
extern char *indexlist(const char *s, int pos);
extern int listlen(const char *s);
extern void printvar(ident *id);
extern void printvar(ident *id, int i);
extern void printfvar(ident *id, float f);
extern void printsvar(ident *id, const char *s);
extern int clampvar(ident *id, int i, int minval, int maxval);
extern float clampfvar(ident *id, float f, float minval, float maxval);
extern void loopiter(ident *id, identstack &stack, const tagval &v);
extern void loopend(ident *id, identstack &stack);

#define loopstart(id, stack) if((id)->type != ID_ALIAS) return; identstack stack;
static inline void loopiter(ident *id, identstack &stack, int i) { tagval v; v.setint(i); loopiter(id, stack, v); }
static inline void loopiter(ident *id, identstack &stack, float f) { tagval v; v.setfloat(f); loopiter(id, stack, v); }

// rendergl
extern physent *camera1;
extern vec worldpos, camdir, camright, camup;
extern float curfov, fovy, aspect;

extern void disablezoom();

extern vec calcavatarpos(const vec &pos, float dist);
extern vec calcmodelpreviewpos(const vec &radius, float &yaw);

extern void damageblend(int n);
extern void damagecompass(int n, const vec &loc);

extern vec minimapcenter, minimapradius, minimapscale;
extern void bindminimap();

extern matrix4 hudmatrix;
extern void resethudmatrix();
extern void pushhudmatrix();
extern void flushhudmatrix(bool flushparams = true);
extern void pophudmatrix(bool flush = true, bool flushparams = true);
extern void pushhudscale(float sx, float sy = 0);
extern void pushhudtranslate(float tx, float ty, float sx = 0, float sy = 0);
extern void resethudshader();

// physics
extern vec collidewall;
extern int collideinside;
extern physent *collideplayer;

extern void moveplayer(physent *pl, int moveres, bool local);
extern bool moveplayer(physent *pl, int moveres, bool local, int curtime);
extern void crouchplayer(physent *pl, int moveres, bool local);
extern bool collide(physent *d, const vec &dir = vec(0, 0, 0), float cutoff = 0.0f, bool playercol = true, bool insideplayercol = false);
extern bool bounce(physent *d, float secs, float elasticity, float waterfric, float grav);
extern bool bounce(physent *d, float elasticity, float waterfric, float grav);
extern void avoidcollision(physent *d, const vec &dir, physent *obstacle, float space);
extern bool overlapsdynent(const vec &o, float radius);
extern bool movecamera(physent *pl, const vec &dir, float dist, float stepdist);
extern void physicsframe();
extern void dropenttofloor(entity *e);
extern bool droptofloor(vec &o, float radius, float height);

extern void vecfromyawpitch(float yaw, float pitch, int move, int strafe, vec &m);
extern void vectoyawpitch(const vec &v, float &yaw, float &pitch);
extern void updatephysstate(physent *d);
extern void cleardynentcache();
extern void updatedynentcache(physent *d);
extern bool entinmap(dynent *d, bool avoidplayers = false);
extern void findplayerspawn(dynent *d, int forceent = -1, int tag = 0);