1 // viewer.hxx -- class for managing a viewer in the flightgear world.
3 // Written by Curtis Olson, started August 1997.
4 // overhaul started October 2000.
5 // partially rewritten by Jim Wilson jim@kelcomaine.com using interface
6 // by David Megginson March 2002
8 // Copyright (C) 1997 - 2000 Curtis L. Olson - curt@flightgear.org
10 // This program is free software; you can redistribute it and/or
11 // modify it under the terms of the GNU General Public License as
12 // published by the Free Software Foundation; either version 2 of the
13 // License, or (at your option) any later version.
15 // This program is distributed in the hope that it will be useful, but
16 // WITHOUT ANY WARRANTY; without even the implied warranty of
17 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 // General Public License for more details.
20 // You should have received a copy of the GNU General Public License
21 // along with this program; if not, write to the Free Software
22 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
32 # error This library requires C++
35 #include <simgear/compiler.h>
36 #include <simgear/constants.h>
38 #include <plib/sg.h> // plib include
42 #include <Main/location.hxx>
44 #define FG_FOV_MIN 0.1
45 #define FG_FOV_MAX 179.9
52 // Define a structure containing view information
53 class FGViewer : public FGSubsystem {
57 enum fgScalingType { // nominal Field Of View actually applies to ...
58 FG_SCALING_WIDTH, // window width
59 FG_SCALING_MAX, // max(width, height)
60 // FG_SCALING_G_MEAN, // geometric_mean(width, height)
61 // FG_SCALING_INDEPENDENT // whole screen
65 FGViewer( fgViewType Type, bool from_model, int from_model_index, bool at_model, int at_model_index );
68 virtual ~FGViewer( void );
70 //////////////////////////////////////////////////////////////////////
71 // Part 1: standard FGSubsystem implementation.
72 //////////////////////////////////////////////////////////////////////
76 virtual void unbind ();
80 //////////////////////////////////////////////////////////////////////
81 // Part 2: user settings.
82 //////////////////////////////////////////////////////////////////////
84 virtual fgViewType getType() const { return _type; }
85 virtual void setType( int type );
87 // Reference geodetic position of view from position...
88 // These are the actual aircraft position (pilot in
89 // pilot view, model in model view).
90 // FIXME: the model view position (ie target positions)
91 // should be in the model class.
92 virtual double getLongitude_deg () const { return _lon_deg; }
93 virtual double getLatitude_deg () const { return _lat_deg; }
94 virtual double getAltitudeASL_ft () const { return _alt_ft; }
95 virtual void setLongitude_deg (double lon_deg);
96 virtual void setLatitude_deg (double lat_deg);
97 virtual void setAltitude_ft (double alt_ft);
98 virtual void setPosition (double lon_deg, double lat_deg, double alt_ft);
100 // Reference geodetic target position...
101 virtual double getTargetLongitude_deg () const { return _target_lon_deg; }
102 virtual double getTargetLatitude_deg () const { return _target_lat_deg; }
103 virtual double getTargetAltitudeASL_ft () const { return _target_alt_ft; }
104 virtual void setTargetLongitude_deg (double lon_deg);
105 virtual void setTargetLatitude_deg (double lat_deg);
106 virtual void setTargetAltitude_ft (double alt_ft);
107 virtual void setTargetPosition (double lon_deg, double lat_deg, double alt_ft);
112 // Position offsets from reference
113 // These offsets position they "eye" in the scene according to a given
114 // location. For example in pilot view they are used to position the
115 // head inside the aircraft.
116 // Note that in pilot view these are applied "before" the orientation
117 // rotations (see below) so that the orientation rotations have the
118 // effect of the pilot staying in his seat and "looking out" in
119 // different directions.
120 // In chase view these are applied "after" the application of the
121 // orientation rotations listed below. This has the effect of the
122 // eye moving around and "looking at" the object (model) from
124 virtual double getXOffset_m () const { return _x_offset_m; }
125 virtual double getYOffset_m () const { return _y_offset_m; }
126 virtual double getZOffset_m () const { return _z_offset_m; }
127 virtual void setXOffset_m (double x_offset_m);
128 virtual void setYOffset_m (double y_offset_m);
129 virtual void setZOffset_m (double z_offset_m);
130 virtual void setPositionOffsets (double x_offset_m,
137 // Reference orientation rotations...
138 // These are rotations that represent the plane attitude effect on
139 // the view (in Pilot view). IE The view frustrum rotates as the plane
140 // turns, pitches, and rolls.
141 // In model view (lookat/chaseview) these end up changing the angle that
142 // the eye is looking at the ojbect (ie the model).
143 // FIXME: the FGModel class should have its own version of these so that
144 // it can generate it's own model rotations.
145 virtual double getRoll_deg () const { return _roll_deg; }
146 virtual double getPitch_deg () const {return _pitch_deg; }
147 virtual double getHeading_deg () const {return _heading_deg; }
148 virtual void setRoll_deg (double roll_deg);
149 virtual void setPitch_deg (double pitch_deg);
150 virtual void setHeading_deg (double heading_deg);
151 virtual void setOrientation (double roll_deg, double pitch_deg, double heading_deg);
152 virtual double getTargetRoll_deg () const { return _target_roll_deg; }
153 virtual double getTargetPitch_deg () const {return _target_pitch_deg; }
154 virtual double getTargetHeading_deg () const {return _target_heading_deg; }
155 virtual void setTargetRoll_deg (double roll_deg);
156 virtual void setTargetPitch_deg (double pitch_deg);
157 virtual void setTargetHeading_deg (double heading_deg);
158 virtual void setTargetOrientation (double roll_deg, double pitch_deg, double heading_deg);
163 // Orientation offsets rotations from reference orientation.
164 // Goal settings are for smooth transition from prior
165 // offset when changing view direction.
166 // These offsets are in ADDITION to the orientation rotations listed
168 // In pilot view they are applied after the position offsets in order to
169 // give the effect of the pilot looking around.
170 // In lookat view they are applied before the position offsets so that
171 // the effect is the eye moving around looking at the object (ie the model)
172 // from different angles.
173 virtual double getRollOffset_deg () const { return _roll_offset_deg; }
174 virtual double getPitchOffset_deg () const { return _pitch_offset_deg; }
175 virtual double getHeadingOffset_deg () const { return _heading_offset_deg; }
176 virtual double getGoalRollOffset_deg () const { return _goal_roll_offset_deg; }
177 virtual double getGoalPitchOffset_deg () const { return _goal_pitch_offset_deg; }
178 virtual double getGoalHeadingOffset_deg () const {return _goal_heading_offset_deg; }
179 virtual void setRollOffset_deg (double roll_offset_deg);
180 virtual void setPitchOffset_deg (double pitch_offset_deg);
181 virtual void setHeadingOffset_deg (double heading_offset_deg);
182 virtual void setGoalRollOffset_deg (double goal_roll_offset_deg);
183 virtual void setGoalPitchOffset_deg (double goal_pitch_offset_deg);
184 virtual void setGoalHeadingOffset_deg (double goal_heading_offset_deg);
185 virtual void setOrientationOffsets (double roll_offset_deg,
186 double heading_offset_deg,
187 double pitch_offset_deg);
191 //////////////////////////////////////////////////////////////////////
192 // Part 3: output vectors and matrices in FlightGear coordinates.
193 //////////////////////////////////////////////////////////////////////
195 // Vectors and positions...
198 virtual float * get_view_pos() {if ( _dirty ) { recalc(); } return _view_pos; }
199 // Get the absolute view position in fgfs coordinates.
200 virtual double * get_absolute_view_pos ();
202 virtual float * get_zero_elev() {if ( _dirty ) { recalc(); } return _zero_elev; }
203 // Get world up vector
204 virtual float *get_world_up() {if ( _dirty ) { recalc(); } return _world_up; }
205 // Get the relative (to scenery center) view position in fgfs coordinates.
206 virtual float * getRelativeViewPos ();
207 // Get the absolute zero-elevation view position in fgfs coordinates.
208 virtual float * getZeroElevViewPos ();
209 // Get surface east vector
210 virtual float *get_surface_east() { if ( _dirty ) { recalc(); } return _surface_east; }
211 // Get surface south vector
212 virtual float *get_surface_south() {if ( _dirty ) { recalc(); } return _surface_south; }
215 virtual const sgVec4 *get_VIEW() { if ( _dirty ) { recalc(); } return VIEW; }
216 virtual const sgVec4 *get_UP() { if ( _dirty ) { recalc(); } return UP; }
218 //////////////////////////////////////////////////////////////////////
219 // Part 4: frustrum data setters and getters
220 //////////////////////////////////////////////////////////////////////
222 virtual void set_fov( double fov_deg ) {
225 virtual double get_fov() const { return _fov_deg; }
226 virtual double get_h_fov(); // Get horizontal fov, in degrees.
227 virtual double get_v_fov(); // Get vertical fov, in degrees.
229 virtual void set_aspect_ratio( double r ) {
232 virtual double get_aspect_ratio() const { return _aspect_ratio; }
234 //////////////////////////////////////////////////////////////////////
235 // Part 5: misc setters and getters
236 //////////////////////////////////////////////////////////////////////
238 inline void set_dirty() { _dirty = true; }
239 inline void set_clean() { _dirty = false; }
244 //////////////////////////////////////////////////////////////////
246 //////////////////////////////////////////////////////////////////
248 // flag forcing a recalc of derived view parameters
251 mutable sgdVec3 _absolute_view_pos;
252 mutable sgVec3 _relative_view_pos;
253 mutable sgVec3 _zero_elev_view_pos;
258 double _target_lon_deg;
259 double _target_lat_deg;
260 double _target_alt_ft;
265 double _target_roll_deg;
266 double _target_pitch_deg;
267 double _target_heading_deg;
269 // Position offsets from center of gravity. The X axis is positive
270 // out the tail, Y is out the right wing, and Z is positive up.
271 // distance in meters
276 // orientation offsets from reference (_goal* are for smoothed transitions)
277 double _roll_offset_deg;
278 double _pitch_offset_deg;
279 double _heading_offset_deg;
280 double _goal_roll_offset_deg;
281 double _goal_pitch_offset_deg;
282 double _goal_heading_offset_deg;
285 fgScalingType _scaling_type;
287 // view is looking from a model
289 int _from_model_index; // number of model (for multi model)
291 // view is looking at a model
293 int _at_model_index; // number of model (for multi model)
295 FGLocation * _location;
296 FGLocation * _target_location;
298 // the nominal field of view (angle, in degrees)
301 // ratio of window width and height; height = width * aspect_ratio
302 double _aspect_ratio;
304 bool _reverse_view_offset;
306 // view position in opengl world coordinates (this is the
307 // abs_view_pos translated to scenery.center)
310 // cartesion coordinates of current lon/lat if at sea level
311 // translated to scenery.center
314 // surface vector heading south
315 sgVec3 _surface_south;
317 // surface vector heading east (used to unambiguously align sky
319 sgVec3 _surface_east;
321 // world up vector (normal to the plane tangent to the earth's
322 // surface at the spot we are directly above
325 // up vector for the view (usually point straight up through the
326 // top of the aircraft
329 // sg versions of our friendly matrices
331 sgMat4 LOCAL, TRANS, LARC_TO_SSG;
333 // Transformation matrix for the view direction offset relative to
334 // the AIRCRAFT matrix
337 //////////////////////////////////////////////////////////////////
338 // private functions //
339 //////////////////////////////////////////////////////////////////
342 void recalcPositionVectors (double lon_deg, double lat_deg, double alt_ft) const;
343 void updateFromModelLocation (FGLocation * location);
344 void recalcOurOwnLocation (double lon_deg, double lat_deg, double alt_ft,
345 double roll_deg, double pitch_deg, double heading_deg);
347 // add to _heading_offset_deg
348 inline void incHeadingOffset_deg( double amt ) {
350 _heading_offset_deg += amt;
353 // add to _pitch_offset_deg
354 inline void incPitchOffset_deg( double amt ) {
356 _pitch_offset_deg += amt;
359 inline void set_reverse_view_offset( bool val ) {
360 _reverse_view_offset = val;
366 #endif // _VIEWER_HXX