1 // location.hxx -- class for determining model location in the flightgear world.
3 // Written by Jim Wilson, David Megginson, started April 2002.
5 // Copyright (C) 2002 Jim Wilson, David Megginson
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 // General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 #ifndef _SG_LOCATION_HXX
25 #define _SG_LOCATION_HXX
29 # error This library requires C++
32 #include <simgear/compiler.h>
33 #include <simgear/constants.h>
34 #include <simgear/math/point3d.hxx>
36 #include <plib/sg.h> // plib include
39 // Define a structure containing view information
49 virtual ~SGLocation( void );
51 //////////////////////////////////////////////////////////////////////
52 // Part 1: standard FGSubsystem implementation.
53 //////////////////////////////////////////////////////////////////////
57 virtual void unbind ();
61 //////////////////////////////////////////////////////////////////////
62 // Part 2: user settings.
63 //////////////////////////////////////////////////////////////////////
65 // Geodetic position of model...
66 virtual double getLongitude_deg () const { return _lon_deg; }
67 virtual double getLatitude_deg () const { return _lat_deg; }
68 virtual double getAltitudeASL_ft () const { return _alt_ft; }
69 virtual void setPosition (double lon_deg, double lat_deg, double alt_ft);
72 // Reference orientation rotations...
73 // These are rotations that represent the plane attitude effect on
74 // the view (in Pilot view). IE The view frustrum rotates as the plane
75 // turns, pitches, and rolls.
76 // In model view (lookat/chaseview) these end up changing the angle that
77 // the eye is looking at the ojbect (ie the model).
78 // FIXME: the FGModel class should have its own version of these so that
79 // it can generate it's own model rotations.
80 virtual double getRoll_deg () const { return _roll_deg; }
81 virtual double getPitch_deg () const {return _pitch_deg; }
82 virtual double getHeading_deg () const {return _heading_deg; }
83 virtual void setOrientation (double roll_deg, double pitch_deg, double heading_deg);
86 //////////////////////////////////////////////////////////////////////
87 // Part 3: output vectors and matrices in FlightGear coordinates.
88 //////////////////////////////////////////////////////////////////////
90 // Vectors and positions...
93 virtual float * get_view_pos() { return _relative_view_pos; }
94 // Get the absolute view position in fgfs coordinates.
95 virtual double * get_absolute_view_pos( const Point3D scenery_center );
97 virtual float * get_zero_elev() { return _zero_elev_view_pos; }
98 // Get world up vector
99 virtual float *get_world_up() { return _world_up; }
100 // Get the relative (to scenery center) view position in fgfs coordinates.
101 virtual float * getRelativeViewPos( const Point3D scenery_center );
102 // Get the absolute zero-elevation view position in fgfs coordinates.
103 virtual float * getZeroElevViewPos( const Point3D scenery_center );
104 // Get surface east vector
105 virtual float *get_surface_east() { return _surface_east; }
106 // Get surface south vector
107 virtual float *get_surface_south() { return _surface_south; }
108 // Elevation of ground under location (based on scenery output)...
109 void set_cur_elev_m ( double elev ) { _cur_elev_m = elev; }
110 inline double get_cur_elev_m () { return _cur_elev_m; }
111 // Interface to current buckets for use with tilemgr...
112 void set_tile_center ( Point3D tile_center ) { _tile_center = tile_center; }
113 inline Point3D get_tile_center () { return _tile_center; }
116 virtual const sgVec4 *getTransformMatrix( const Point3D scenery_center ) {
118 recalc( scenery_center );
122 virtual const sgVec4 *getCachedTransformMatrix() { return TRANS; }
123 virtual const sgVec4 *getUpMatrix( const Point3D scenery_center ) {
125 recalc( scenery_center );
129 virtual const sgVec4 *getCachedUpMatrix() { return UP; }
134 //////////////////////////////////////////////////////////////////
136 //////////////////////////////////////////////////////////////////
138 // flag forcing a recalc of derived view parameters
141 mutable sgdVec3 _absolute_view_pos;
142 mutable sgVec3 _relative_view_pos;
143 mutable sgVec3 _zero_elev_view_pos;
153 // elevation of ground under this location...
155 Point3D _tile_center;
157 // surface vector heading south
158 sgVec3 _surface_south;
160 // surface vector heading east (used to unambiguously align sky
162 sgVec3 _surface_east;
164 // world up vector (normal to the plane tangent to the earth's
165 // surface at the spot we are directly above
168 // sg versions of our friendly matrices
171 //////////////////////////////////////////////////////////////////
172 // private functions //
173 //////////////////////////////////////////////////////////////////
175 void recalc( const Point3D scenery_center );
176 void recalcPosition( double lon_deg, double lat_deg, double alt_ft,
177 const Point3D scenery_center ) const;
179 inline void set_dirty() { _dirty = true; }
180 inline void set_clean() { _dirty = false; }
185 #endif // _SG_LOCATION_HXX