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>
37 #include <simgear/scene/model/location.hxx>
39 #include <plib/sg.h> // plib include
43 #define FG_FOV_MIN 0.1
44 #define FG_FOV_MAX 179.9
51 // Define a structure containing view information
52 class FGViewer : public FGSubsystem {
56 enum fgScalingType { // nominal Field Of View actually applies to ...
57 FG_SCALING_WIDTH, // window width
58 FG_SCALING_MAX // max(width, height)
59 // FG_SCALING_G_MEAN, // geometric_mean(width, height)
60 // FG_SCALING_INDEPENDENT // whole screen
64 FGViewer( fgViewType Type, bool from_model, int from_model_index,
65 bool at_model, int at_model_index,
66 double x_offset_m, double y_offset_m, double z_offset_m,
67 double heading_offset_deg, double pitch_offset_deg,
68 double roll_offset_deg, double fov_deg,
69 double target_x_offset_m, double target_y_offset_m,
70 double target_z_offset_m, double near_m );
73 virtual ~FGViewer( void );
75 //////////////////////////////////////////////////////////////////////
76 // Part 1: standard FGSubsystem implementation.
77 //////////////////////////////////////////////////////////////////////
81 virtual void unbind ();
82 void update (double dt);
85 //////////////////////////////////////////////////////////////////////
86 // Part 2: user settings.
87 //////////////////////////////////////////////////////////////////////
89 virtual fgViewType getType() const { return _type; }
90 virtual void setType( int type );
92 // Reference geodetic position of view from position...
93 // These are the actual aircraft position (pilot in
94 // pilot view, model in model view).
95 // FIXME: the model view position (ie target positions)
96 // should be in the model class.
97 virtual double getLongitude_deg () const { return _lon_deg; }
98 virtual double getLatitude_deg () const { return _lat_deg; }
99 virtual double getAltitudeASL_ft () const { return _alt_ft; }
100 virtual void setLongitude_deg (double lon_deg);
101 virtual void setLatitude_deg (double lat_deg);
102 virtual void setAltitude_ft (double alt_ft);
103 virtual void setPosition (double lon_deg, double lat_deg, double alt_ft);
105 // Reference geodetic target position...
106 virtual double getTargetLongitude_deg () const { return _target_lon_deg; }
107 virtual double getTargetLatitude_deg () const { return _target_lat_deg; }
108 virtual double getTargetAltitudeASL_ft () const { return _target_alt_ft; }
109 virtual void setTargetLongitude_deg (double lon_deg);
110 virtual void setTargetLatitude_deg (double lat_deg);
111 virtual void setTargetAltitude_ft (double alt_ft);
112 virtual void setTargetPosition (double lon_deg, double lat_deg, double alt_ft);
117 // Position offsets from reference
118 // These offsets position they "eye" in the scene according to a given
119 // location. For example in pilot view they are used to position the
120 // head inside the aircraft.
121 // Note that in pilot view these are applied "before" the orientation
122 // rotations (see below) so that the orientation rotations have the
123 // effect of the pilot staying in his seat and "looking out" in
124 // different directions.
125 // In chase view these are applied "after" the application of the
126 // orientation rotations listed below. This has the effect of the
127 // eye moving around and "looking at" the object (model) from
129 virtual double getXOffset_m () const { return _x_offset_m; }
130 virtual double getYOffset_m () const { return _y_offset_m; }
131 virtual double getZOffset_m () const { return _z_offset_m; }
132 virtual double getTargetXOffset_m () const { return _target_x_offset_m; }
133 virtual double getTargetYOffset_m () const { return _target_y_offset_m; }
134 virtual double getTargetZOffset_m () const { return _target_z_offset_m; }
135 virtual void setXOffset_m (double x_offset_m);
136 virtual void setYOffset_m (double y_offset_m);
137 virtual void setZOffset_m (double z_offset_m);
138 virtual void setTargetXOffset_m (double x_offset_m);
139 virtual void setTargetYOffset_m (double y_offset_m);
140 virtual void setTargetZOffset_m (double z_offset_m);
141 virtual void setPositionOffsets (double x_offset_m,
148 // Reference orientation rotations...
149 // These are rotations that represent the plane attitude effect on
150 // the view (in Pilot view). IE The view frustrum rotates as the plane
151 // turns, pitches, and rolls.
152 // In model view (lookat/chaseview) these end up changing the angle that
153 // the eye is looking at the ojbect (ie the model).
154 // FIXME: the FGModel class should have its own version of these so that
155 // it can generate it's own model rotations.
156 virtual double getRoll_deg () const { return _roll_deg; }
157 virtual double getPitch_deg () const {return _pitch_deg; }
158 virtual double getHeading_deg () const {return _heading_deg; }
159 virtual void setRoll_deg (double roll_deg);
160 virtual void setPitch_deg (double pitch_deg);
161 virtual void setHeading_deg (double heading_deg);
162 virtual void setOrientation (double roll_deg, double pitch_deg, double heading_deg);
163 virtual double getTargetRoll_deg () const { return _target_roll_deg; }
164 virtual double getTargetPitch_deg () const {return _target_pitch_deg; }
165 virtual double getTargetHeading_deg () const {return _target_heading_deg; }
166 virtual void setTargetRoll_deg (double roll_deg);
167 virtual void setTargetPitch_deg (double pitch_deg);
168 virtual void setTargetHeading_deg (double heading_deg);
169 virtual void setTargetOrientation (double roll_deg, double pitch_deg, double heading_deg);
174 // Orientation offsets rotations from reference orientation.
175 // Goal settings are for smooth transition from prior
176 // offset when changing view direction.
177 // These offsets are in ADDITION to the orientation rotations listed
179 // In pilot view they are applied after the position offsets in order to
180 // give the effect of the pilot looking around.
181 // In lookat view they are applied before the position offsets so that
182 // the effect is the eye moving around looking at the object (ie the model)
183 // from different angles.
184 virtual double getRollOffset_deg () const { return _roll_offset_deg; }
185 virtual double getPitchOffset_deg () const { return _pitch_offset_deg; }
186 virtual double getHeadingOffset_deg () const { return _heading_offset_deg; }
187 virtual double getGoalRollOffset_deg () const { return _goal_roll_offset_deg; }
188 virtual double getGoalPitchOffset_deg () const { return _goal_pitch_offset_deg; }
189 virtual double getGoalHeadingOffset_deg () const {return _goal_heading_offset_deg; }
190 virtual void setRollOffset_deg (double roll_offset_deg);
191 virtual void setPitchOffset_deg (double pitch_offset_deg);
192 virtual void setHeadingOffset_deg (double heading_offset_deg);
193 virtual void setGoalRollOffset_deg (double goal_roll_offset_deg);
194 virtual void setGoalPitchOffset_deg (double goal_pitch_offset_deg);
195 virtual void setGoalHeadingOffset_deg (double goal_heading_offset_deg);
196 virtual void setOrientationOffsets (double roll_offset_deg,
197 double heading_offset_deg,
198 double pitch_offset_deg);
202 //////////////////////////////////////////////////////////////////////
203 // Part 3: output vectors and matrices in FlightGear coordinates.
204 //////////////////////////////////////////////////////////////////////
206 // Vectors and positions...
209 virtual float * get_view_pos() {if ( _dirty ) { recalc(); } return _view_pos; }
210 // Get the absolute view position in fgfs coordinates.
211 virtual double * get_absolute_view_pos ();
213 virtual float * get_zero_elev() {if ( _dirty ) { recalc(); } return _zero_elev; }
214 // Get world up vector
215 virtual float *get_world_up() {if ( _dirty ) { recalc(); } return _world_up; }
216 // Get the relative (to scenery center) view position in fgfs coordinates.
217 virtual float * getRelativeViewPos ();
218 // Get the absolute zero-elevation view position in fgfs coordinates.
219 virtual float * getZeroElevViewPos ();
220 // Get surface east vector
221 virtual float *get_surface_east() { if ( _dirty ) { recalc(); } return _surface_east; }
222 // Get surface south vector
223 virtual float *get_surface_south() {if ( _dirty ) { recalc(); } return _surface_south; }
226 virtual const sgVec4 *get_VIEW() { if ( _dirty ) { recalc(); } return VIEW; }
227 virtual const sgVec4 *get_UP() { if ( _dirty ) { recalc(); } return UP; }
229 //////////////////////////////////////////////////////////////////////
230 // Part 4: View and frustrum data setters and getters
231 //////////////////////////////////////////////////////////////////////
233 virtual void set_fov( double fov_deg ) {
236 virtual double get_fov() const { return _fov_deg; }
237 virtual double get_h_fov(); // Get horizontal fov, in degrees.
238 virtual double get_v_fov(); // Get vertical fov, in degrees.
240 virtual void set_aspect_ratio( double r ) {
243 virtual double get_aspect_ratio() const { return _aspect_ratio; }
245 virtual double getNear_m () const { return _ground_level_nearplane_m; }
246 inline void setNear_m (double near_m) {
247 _ground_level_nearplane_m = near_m;
250 //////////////////////////////////////////////////////////////////////
251 // Part 5: misc setters and getters
252 //////////////////////////////////////////////////////////////////////
254 inline void set_dirty() { _dirty = true; }
255 inline void set_clean() { _dirty = false; }
257 // return eye location...
258 virtual SGLocation * getSGLocation () const { return _location; }
263 //////////////////////////////////////////////////////////////////
265 //////////////////////////////////////////////////////////////////
267 // flag forcing a recalc of derived view parameters
270 mutable sgdVec3 _absolute_view_pos;
271 mutable sgVec3 _relative_view_pos;
272 mutable sgVec3 _zero_elev_view_pos;
277 double _target_lon_deg;
278 double _target_lat_deg;
279 double _target_alt_ft;
284 double _target_roll_deg;
285 double _target_pitch_deg;
286 double _target_heading_deg;
288 // Position offsets from FDM origin. The X axis is positive
289 // out the tail, Y is out the right wing, and Z is positive up.
290 // distance in meters
295 // Target offsets from FDM origin (for "lookat" targets) The X
296 // axis is positive out the tail, Y is out the right wing, and Z
297 // is positive up. distance in meters
298 double _target_x_offset_m;
299 double _target_y_offset_m;
300 double _target_z_offset_m;
303 // orientation offsets from reference (_goal* are for smoothed transitions)
304 double _roll_offset_deg;
305 double _pitch_offset_deg;
306 double _heading_offset_deg;
307 double _goal_roll_offset_deg;
308 double _goal_pitch_offset_deg;
309 double _goal_heading_offset_deg;
311 // used to set nearplane when at ground level for this view
312 double _ground_level_nearplane_m;
315 fgScalingType _scaling_type;
317 // view is looking from a model
319 int _from_model_index; // number of model (for multi model)
321 // view is looking at a model
323 int _at_model_index; // number of model (for multi model)
325 SGLocation * _location;
326 SGLocation * _target_location;
328 // the nominal field of view (angle, in degrees)
331 // ratio of window width and height; height = width * aspect_ratio
332 double _aspect_ratio;
334 bool _reverse_view_offset;
336 // view position in opengl world coordinates (this is the
337 // abs_view_pos translated to scenery.center)
340 // cartesion coordinates of current lon/lat if at sea level
341 // translated to scenery.center
344 // surface vector heading south
345 sgVec3 _surface_south;
347 // surface vector heading east (used to unambiguously align sky
349 sgVec3 _surface_east;
351 // world up vector (normal to the plane tangent to the earth's
352 // surface at the spot we are directly above
355 // up vector for the view (usually point straight up through the
356 // top of the aircraft
359 // sg versions of our friendly matrices
361 sgMat4 LOCAL, ATLOCAL, TRANS, LARC_TO_SSG;
363 // Transformation matrix for the view direction offset relative to
364 // the AIRCRAFT matrix
367 //////////////////////////////////////////////////////////////////
368 // private functions //
369 //////////////////////////////////////////////////////////////////
372 void recalcLookFrom();
374 void copyLocationData();
375 void updateFromModelLocation (SGLocation * location);
376 void updateAtModelLocation (SGLocation * location);
377 void recalcOurOwnLocation (SGLocation * location, double lon_deg, double lat_deg, double alt_ft,
378 double roll_deg, double pitch_deg, double heading_deg);
380 // add to _heading_offset_deg
381 inline void incHeadingOffset_deg( double amt ) {
383 _heading_offset_deg += amt;
386 // add to _pitch_offset_deg
387 inline void incPitchOffset_deg( double amt ) {
389 _pitch_offset_deg += amt;
392 inline void set_reverse_view_offset( bool val ) {
393 _reverse_view_offset = val;
399 #endif // _VIEWER_HXX