My non-precision approach model had been one or more IAFs and then a common core...

[flightgear.git] / src / Instrumentation / dclgps.hxx

// dclgps.hxx - a class to extend the operation of FG's current GPS
// code, and provide support for a KLN89-specific instrument.  It
// is envisioned that eventually this file and class will be split
// up between current FG code and new KLN89-specific code and removed.
//
// Written by David Luff, started 2005.
//
// Copyright (C) 2005 - David C Luff:  daveluff --AT-- ntlworld --D0T-- 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 2 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, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
//
// $Id$

#ifndef _DCLGPS_HXX
#define _DCLGPS_HXX

#include "render_area_2d.hxx"
#include <string>
#include <list>
#include <vector>
#include <map>

#include <simgear/structure/subsystem_mgr.hxx>
#include <Navaids/positioned.hxx>

class SGTime;
class FGPositioned;

// XXX fix me
class FGNavRecord;
class FGAirport;
class FGFix;

enum GPSDistanceUnits {
        GPS_DIST_UNITS_NM = 0,
        GPS_DIST_UNITS_KM
};

enum GPSSpeedUnits {
        GPS_VEL_UNITS_KT,
        GPS_VEL_UNITS_KPH
};

enum GPSAltitudeUnits {
        GPS_ALT_UNITS_FT,
        GPS_ALT_UNITS_M
};

enum GPSPressureUnits {
        GPS_PRES_UNITS_IN = 1,
        GPS_PRES_UNITS_MB,
        GPS_PRES_UNITS_HP
};

// --------------------- Waypoint / Flightplan stuff -----------------------------
// This should be merged with other similar stuff in FG at some point.

// NOTE - ORDERING IS IMPORTANT HERE - it matches the Bendix-King page ordering!
enum GPSWpType {
        GPS_WP_APT = 0,
        GPS_WP_VOR,
        GPS_WP_NDB,
        GPS_WP_INT,
        GPS_WP_USR,
        GPS_WP_VIRT             // Used for virtual waypoints, such as the start of DTO operation.
};

enum GPSAppWpType {
        GPS_IAF,                // Initial approach fix
        GPS_IAP,                // Waypoint on approach sequence that isn't any of the others.
        GPS_FAF,                // Final approach fix
        GPS_MAP,                // Missed approach point
        GPS_MAHP,               // Initial missed approach holding point.
    GPS_HDR,        // A virtual 'waypoint' to represent the approach header in the fpl page
    GPS_FENCE,      // A virtual 'waypoint' to represent the NO WPT SEQ fence.
    GPS_APP_NONE    // Not part of the approach sequence - the default.
};

ostream& operator << (ostream& os, GPSAppWpType type);

struct GPSWaypoint {
    GPSWaypoint();
  
  GPSWaypoint(const std::string& aIdent, float lat, float lon, GPSWpType aType);
  
  static GPSWaypoint* createFromPositioned(const FGPositioned* aFix);
  
    ~GPSWaypoint();
        string GetAprId();      // Returns the id with i, f, m or h added if appropriate. (Initial approach fix, final approach fix, etc)
        string id;
        float lat;      // Radians
        float lon;      // Radians
        GPSWpType type;
        GPSAppWpType appType;   // only used for waypoints that are part of an approach sequence
};

typedef vector < GPSWaypoint* > gps_waypoint_array;
typedef gps_waypoint_array::iterator gps_waypoint_array_iterator;
typedef map < string, gps_waypoint_array > gps_waypoint_map;
typedef gps_waypoint_map::iterator gps_waypoint_map_iterator;
typedef gps_waypoint_map::const_iterator gps_waypoint_map_const_iterator;

class GPSFlightPlan {
public:
        vector<GPSWaypoint*> waypoints;
        inline bool IsEmpty() { return(waypoints.size() == 0); }
};

// TODO - probably de-public the internals of the next 2 classes and add some methods!
// Instrument approach procedure base class
class FGIAP {
public:
        FGIAP();
        virtual ~FGIAP() = 0;
//protected:

        string _id;             // The ID of the airport this approach is for
        string _name;   // The approach name, eg "VOR/DME OR GPS-B"
        string _abbrev; // The abbreviation the GPS unit uses - eg "VOR/D" in this instance.  Possibly GPS model specific.
        string _rwyStr; // The string used to specify the rwy - eg "B" in this instance.
        bool _precision;        // True for precision approach, false for non-precision.
};

// Non-precision instrument approach procedure
class FGNPIAP : public FGIAP {
public:
        FGNPIAP();
        ~FGNPIAP();
//private:
public:
        vector<GPSFlightPlan*> _approachRoutes; // The approach route(s) from the IAF(s) to the IF.
                                                                                        // NOTE: It is an assumption in the code that uses this that there is a unique IAF per approach route.
        vector<GPSWaypoint*> _IAP;      // The compulsory waypoints of the approach procedure (may duplicate one of the above).
                                                                // _IAP includes the FAF and MAF.
        vector<GPSWaypoint*> _MAP;      // The missed approach procedure (doesn't include the MAF).
};

typedef vector < FGIAP* > iap_list_type;
typedef map < string, iap_list_type > iap_map_type;
typedef iap_map_type::iterator iap_map_iterator;

//      A class to encapsulate hr:min representation of time. 

class ClockTime {
public:
    ClockTime();
    ClockTime(int hr, int min);
    ~ClockTime();
    inline void set_hr(int hr) { _hr = hr; }
    inline int hr() const { return(_hr); } 
    inline void set_min(int min) { _min = min; }
    inline int min() const { return(_min); }
    
    ClockTime operator+ (const ClockTime& t) {
        int cumMin = _hr * 60 + _min + t.hr() * 60 + t.min();
        ClockTime t2(cumMin / 60, cumMin % 60);
        return(t2);
    }
    // Operator - has a max difference of 23:59,
    // and assumes the day has wrapped if the second operand
    // is larger that the first.
    // eg. 2:59 - 3:00 = 23:59
    ClockTime operator- (const ClockTime& t) {
        int diff = (_hr * 60 + _min) - (t.hr() * 60 + t.min());
        if(diff < 0) { diff += 24 * 60; }
        ClockTime t2(diff / 60, diff % 60);
        return(t2);
    }
    friend ostream& operator<< (ostream& out, const ClockTime& t);

private:
    int _hr;
    int _min;
};

// ------------------------------------------------------------------------------

// TODO - merge generic GPS functions instead and split out KLN specific stuff.
class DCLGPS : public SGSubsystem {
        
public:
        DCLGPS(RenderArea2D* instrument);
        virtual ~DCLGPS() = 0;
        
        virtual void draw(osg::State& state);
        
        virtual void init();
        virtual void bind();
        virtual void unbind();
        virtual void update(double dt);

        // Render string s in display field field at position x, y
        // WHERE POSITION IS IN CHARACTER UNITS!
        // zero y at bottom?
        virtual void DrawText(const string& s, int field, int px, int py, bool bold = false);
        
        // Render a char at a given position as above
        virtual void DrawChar(char c, int field, int px, int py, bool bold = false);
        
        virtual void ToggleOBSMode();
        
        // Set the number of fields
        inline void SetNumFields(int n) { _nFields = (n > _maxFields ? _maxFields : (n < 1 ? 1 : n)); }
        
        // Set Units
        // m if true, ft if false
        inline void SetAltUnitsSI(bool b) { _altUnits = (b ? GPS_ALT_UNITS_M : GPS_ALT_UNITS_FT); }
        // Returns true if alt units are SI (m), false if ft
        inline bool GetAltUnitsSI() { return(_altUnits == GPS_ALT_UNITS_M ? true : false); }
        // km and k/h if true, nm and kt if false
        inline void SetDistVelUnitsSI(bool b) { _distUnits = (b ? GPS_DIST_UNITS_KM : GPS_DIST_UNITS_NM); _velUnits = (b ? GPS_VEL_UNITS_KPH : GPS_VEL_UNITS_KT); }
        // Returns true if dist/vel units are SI
        inline bool GetDistVelUnitsSI() { return(_distUnits == GPS_DIST_UNITS_KM && _velUnits == GPS_VEL_UNITS_KPH ? true : false); }
        // Set baro units - 1 = in, 2 = mB, 3 = hP   Wrapping if for the convienience of the GPS setter.
        void SetBaroUnits(int n, bool wrap = false);
        // Get baro units: 1 = in, 2 = mB, 3 = hP
        inline int GetBaroUnits() { return((int)_baroUnits); }
        
        // It is expected that specific GPS units will override these functions.
        // Increase the CDI full-scale deflection (ie. increase the nm per dot) one (GPS unit dependent) increment.  Wraps if necessary (GPS unit dependent).
        virtual void CDIFSDIncrease();
        // Ditto for decrease the distance per dot
        virtual void CDIFSDDecrease();
        
        // Host specifc
        ////inline void SetOverlays(Overlays* overlays) { _overlays = overlays; }
        
        virtual void CreateDefaultFlightPlans();
        
        void SetOBSFromWaypoint();
        
        GPSWaypoint* GetActiveWaypoint();
        // Get the (zero-based) position of the active waypoint in the active flightplan
        // Returns -1 if no active waypoint.
        int GetActiveWaypointIndex();
        // Ditto for an arbitrary waypoint id
        int GetWaypointIndex(const string& id);
        
        // Returns meters
        float GetDistToActiveWaypoint();
        // Returns degrees (magnetic)
        float GetHeadingToActiveWaypoint();
        // Returns degrees (magnetic)
        float GetHeadingFromActiveWaypoint();
        // Get the time to the active waypoint in seconds.
        // Returns -1 if groundspeed < 30 kts
        double GetTimeToActiveWaypoint();
        // Get the time to the final waypoint in seconds.
        // Returns -1 if groundspeed < 30 kts
        double GetETE();
        // Get the time to a given waypoint (spec'd by ID) in seconds.
        // returns -1 if groundspeed is less than 30kts.
        // If the waypoint is an unreached part of the active flight plan the time will be via each leg.
        // otherwise it will be a direct-to time.
        double GetTimeToWaypoint(const string& id);
        
        // Return true if waypoint alerting is occuring
        inline bool GetWaypointAlert() const { return(_waypointAlert); }
        // Return true if in OBS mode
        inline bool GetOBSMode() const { return(_obsMode); }
        // Return true if in Leg mode
        inline bool GetLegMode() const { return(!_obsMode); }
        
        // Clear a flightplan
        void ClearFlightPlan(int n);
        void ClearFlightPlan(GPSFlightPlan* fp);
        
        // Returns true if an approach is loaded/armed/active in the active flight plan
        inline bool ApproachLoaded() const { return(_approachLoaded); }
        inline bool GetApproachArm() const { return(_approachArm); }
        inline bool GetApproachActive() const { return(_approachActive); }
        double GetCDIDeflection() const;
        inline bool GetToFlag() const { return(_headingBugTo); }
        
        // Initiate Direct To operation to the supplied ID.
        void DtoInitiate(const string& id);
        // Cancel Direct To operation
        void DtoCancel();
        
protected:
        // Maximum number of display fields for this device
        int _maxFields;
        // Current number of on-screen fields
        int _nFields;
        // Full x border
        int _xBorder;
        // Full y border
        int _yBorder;
        // Lower (y) border per field
        int _yFieldBorder[4];
        // Left (x) border per field
        int _xFieldBorder[4];
        // Field start in x dir (border is part of field since it is the normal char border - sometimes map mode etc draws in it)
        int _xFieldStart[4];
        // Field start in y dir (for completeness - KLN89 only has vertical divider.
        int _yFieldStart[4];
        
        // The number of pages on the cyclic knob control
        unsigned int _nPages;
        // The current page we're on (Not sure how this ties in with extra pages such as direct or nearest).
        unsigned int _curPage;
        
        // 2D rendering area
        RenderArea2D* _instrument;
        
        // Units
        GPSSpeedUnits _velUnits;
        GPSDistanceUnits _distUnits;
        GPSPressureUnits _baroUnits;
        GPSAltitudeUnits _altUnits;
        
        // CDI full-scale deflection, specified either as an index into a vector of values (standard values) or as a double precision float (intermediate values).
        // This will influence how an externally driven CDI will display as well as the NAV1 page.
        // Hence the variables are located here, not in the nav page class.
        vector<float> _cdiScales;
        unsigned int _currentCdiScaleIndex;
        bool _cdiScaleTransition;               // Set true when the floating CDI value is used during transitions
        double _currentCdiScale;        // The floating value to use.
        unsigned int _targetCdiScaleIndex;      // The target indexed value to attain during a transition.
        unsigned int _sourceCdiScaleIndex;      // The source indexed value during a transition - so we know which way we're heading!
        // Timers to handle the transitions - not sure if we need these.
        double _apprArmTimer;
        double _apprActvTimer;
        double _cdiTransitionTime;      // Time for transition to occur in - normally 30sec but may be quicker if time to FAF < 30sec?
        // 
        
        // Data and lookup functions


protected:
        // Find first of any type of waypoint by id.  (TODO - Possibly we should return multiple waypoints here).
  GPSWaypoint* FindFirstById(const string& id) const;
  GPSWaypoint* FindFirstByExactId(const string& id) const;
   
        FGNavRecord* FindFirstVorById(const string& id, bool &multi, bool exact = false);
        FGNavRecord* FindFirstNDBById(const string& id, bool &multi, bool exact = false);
        const FGAirport* FindFirstAptById(const string& id, bool &multi, bool exact = false);
        const FGFix* FindFirstIntById(const string& id, bool &multi, bool exact = false);
        // Find the closest VOR to a position in RADIANS.
        FGNavRecord* FindClosestVor(double lat_rad, double lon_rad);

  // helper to implement the above FindFirstXXX methods
  FGPositioned* FindTypedFirstById(const std::string& id, FGPositioned::Type ty, bool &multi, bool exact);

        // Position, orientation and velocity.
        // These should be read from FG's built-in GPS logic if possible.
        // Use the property node pointers below to do this.
    SGPropertyNode_ptr _lon_node;
    SGPropertyNode_ptr _lat_node;
    SGPropertyNode_ptr _alt_node;
        SGPropertyNode_ptr _grnd_speed_node;
        SGPropertyNode_ptr _true_track_node;
        SGPropertyNode_ptr _mag_track_node;
        // Present position. (Radians)
        double _lat, _lon;
        // Present altitude (ft). (Yuk! but it saves converting ft->m->ft every update).
        double _alt;
        // Reported position as measured by GPS.  For now this is the same
        // as present position, but in the future we might want to model
        // GPS lat and lon errors.
        // Note - we can depriciate _gpsLat and _gpsLon if we implement error handling in FG
        // gps code and not our own.
        double _gpsLat, _gpsLon;  //(Radians)
        // Hack - it seems that the GPS gets initialised before FG's initial position is properly set.
        // By checking for abnormal slew in the position we can force a re-initialisation of active flight
        // plan leg and anything else that might be affected.
        // TODO - sort FlightGear's initialisation order properly!!!
        double _checkLat, _checkLon;    // (Radians)
        double _groundSpeed_ms; // filtered groundspeed (m/s)
        double _groundSpeed_kts;        // ditto in knots
        double _track;                  // filtered true track (degrees)
        double _magTrackDeg;    // magnetic track in degrees calculated from true track above
        
        // _navFlagged is set true when GPS navigation is either not possible or not logical.
        // This includes not receiving adequate signals, and not having an active flightplan entered.
        bool _navFlagged;
        
        // Positional functions copied from ATCutils that might get replaced
        // INPUT in RADIANS, returns DEGREES!
        // Magnetic
        double GetMagHeadingFromTo(double latA, double lonA, double latB, double lonB);
        // True
        //double GetHeadingFromTo(double latA, double lonA, double latB, double lonB);
        
        // Given two positions (lat & lon in RADIANS), get the HORIZONTAL separation (in meters)
        //double GetHorizontalSeparation(double lat1, double lon1, double lat2, double lon2);
        
        // Proper great circle positional functions from The Aviation Formulary
        // Returns distance in Nm, input in RADIANS.
        double GetGreatCircleDistance(double lat1, double lon1, double lat2, double lon2) const;
        
        // Input in RADIANS, output in DEGREES.
        // True
        double GetGreatCircleCourse(double lat1, double lon1, double lat2, double lon2) const;
        
        // Return a position on a radial from wp1 given distance d (nm) and magnetic heading h (degrees)
        // Note that d should be less that 1/4 Earth diameter!
        GPSWaypoint GetPositionOnMagRadial(const GPSWaypoint& wp1, double d, double h);
        
        // Return a position on a radial from wp1 given distance d (nm) and TRUE heading h (degrees)
        // Note that d should be less that 1/4 Earth diameter!
        GPSWaypoint GetPositionOnRadial(const GPSWaypoint& wp1, double d, double h);
        
        // Calculate the current cross-track deviation in nm.
        // Returns zero if a sensible value cannot be calculated.
        double CalcCrossTrackDeviation() const;
        
        // Calculate the cross-track deviation between 2 arbitrary waypoints in nm.
        // Returns zero if a sensible value cannot be calculated.
        double CalcCrossTrackDeviation(const GPSWaypoint& wp1, const GPSWaypoint& wp2) const;
        
        // Flightplans
        // GPS can have up to _maxFlightPlans flightplans stored, PLUS an active FP which may or my not be one of the stored ones.
        // This is from KLN89, but is probably not far off the mark for most if not all GPS.
        vector<GPSFlightPlan*> _flightPlans;
        unsigned int _maxFlightPlans;
        GPSFlightPlan* _activeFP;
        
        // Modes of operation.
        // This is currently somewhat Bendix-King specific, but probably applies fundamentally to other units as well
        // Mode defaults to leg, but is OBS if _obsMode is true.
        bool _obsMode;
        // _dto is set true for DTO operation
        bool _dto;
        // In leg mode, we need to know if we are displaying a from and to waypoint, or just the to waypoint (eg. when OBS mode is cancelled).
        bool _fullLegMode;
        // In OBS mode we need to know the set OBS heading
        int _obsHeading;
        
        // Operational variables
        GPSWaypoint _activeWaypoint;
        GPSWaypoint _fromWaypoint;
        float _dist2Act;
        float _crosstrackDist;  // UNITS ??????????
        double _eta;    // ETA in SECONDS to active waypoint.
        // Desired track for active leg, true and magnetic, in degrees
        double _dtkTrue, _dtkMag;
        bool _headingBugTo;             // Set true when the heading bug is TO, false when FROM.
        bool _waypointAlert;    // Set true when waypoint alerting is happening. (This is a variable NOT a user-setting).
        bool _departed;         // Set when groundspeed first exceeds 30kts.
        string _departureTimeString;    // Ditto.
        double _elapsedTime;    // Elapsed time in seconds since departure
        ClockTime _powerOnTime;         // Time (hr:min) of unit power-up.
        bool _powerOnTimerSet;          // Indicates that we have set the above following power-up.
        void SetPowerOnTimer();
public:
        void ResetPowerOnTimer();
        // Set the alarm to go off at a given time.
        inline void SetAlarm(int hr, int min) {
                _alarmTime.set_hr(hr);
                _alarmTime.set_min(min);
                _alarmSet = true;
        }
protected:
        ClockTime _alarmTime;
        bool _alarmSet;
        
        // Configuration that affects flightplan operation
        bool _turnAnticipationEnabled;
        
        // Configuration that affects general operation
        bool _suaAlertEnabled;          // Alert user to potential SUA entry
        bool _altAlertEnabled;          // Alert user to min safe alt violation
        
        // Magvar stuff.  Might get some of this stuff (such as time) from FG in future.
        SGTime* _time;
        
        list<string> _messageStack;
        
        virtual void CreateFlightPlan(GPSFlightPlan* fp, vector<string> ids, vector<GPSWpType> wps);
        
        // Orientate the GPS unit to a flightplan - ie. figure out from current position
        // and possibly orientation which leg of the FP we are on.
        virtual void OrientateToFlightPlan(GPSFlightPlan* fp);
        
        // Ditto for active fp.  Probably all we need really!
        virtual void OrientateToActiveFlightPlan();
        
        int _cleanUpPage;       // -1 => no cleanup required.
        
        // IAP stuff
        iap_map_type _np_iap;   // Non-precision approaches
        iap_map_type _pr_iap;   // Precision approaches
        bool _approachLoaded;   // Set true when an approach is loaded in the active flightplan
        bool _approachArm;              // Set true when in approach-arm mode
        bool _approachReallyArmed;      // Apparently, approach-arm mode can be set from an external GPS-APR switch outside 30nm from airport,
                                                                // but the CDI scale change doesn't happen until 30nm from airport.  Bizarre that it can be armed without
                                                                // the scale change, but it's in the manual...
        bool _approachActive;   // Set true when in approach-active mode
        GPSFlightPlan* _approachFP;     // Current approach - not necessarily loaded.
        string _approachID;             // ID of the airport we have an approach loaded for - bit of a hack that can hopefully be removed in future.
        // More hackery since we aren't actually storing an approach class... Doh!
        string _approachAbbrev;
        string _approachRwyStr;
};

#endif  // _DCLGPS_HXX