1 // FGAIBase - abstract base class for AI objects
2 // Written by David Culp, started Nov 2003, based on
3 // David Luff's FGAIEntity class.
4 // - davidculp2@comcast.net
6 // This program is free software; you can redistribute it and/or
7 // modify it under the terms of the GNU General Public License as
8 // published by the Free Software Foundation; either version 2 of the
9 // License, or (at your option) any later version.
11 // This program is distributed in the hope that it will be useful, but
12 // WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 // General Public License for more details.
16 // You should have received a copy of the GNU General Public License
17 // along with this program; if not, write to the Free Software
18 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
25 #include <simgear/compiler.h>
32 #include <simgear/math/point3d.hxx>
33 #include <simgear/math/polar3d.hxx>
34 #include <simgear/math/sg_geodesy.hxx>
35 #include <simgear/misc/sg_path.hxx>
36 #include <simgear/scene/model/location.hxx>
37 #include <simgear/scene/model/model.hxx>
38 #include <simgear/scene/model/personality.hxx>
39 #include <simgear/debug/logstream.hxx>
40 #include <simgear/props/props.hxx>
42 #include <Main/globals.hxx>
43 #include <Scenery/scenery.hxx>
47 #include "AIManager.hxx"
50 const double FGAIBase::e = 2.71828183;
51 const double FGAIBase::lbs_to_slugs = 0.031080950172; //conversion factor
54 FGAIBase::FGAIBase(object_type ot) :
58 _refID( _newAIModelID() ),
61 tgt_heading = hdg = tgt_altitude_ft = tgt_speed = 0.0;
62 tgt_roll = roll = tgt_pitch = tgt_yaw = tgt_vs = vs = pitch = 0.0;
63 bearing = elevation = range = rdot = 0.0;
64 x_shift = y_shift = rotation = 0.0;
72 FGAIBase::~FGAIBase() {
73 // Unregister that one at the scenery manager
74 if (globals->get_scenery()) {
75 globals->get_scenery()->unregister_placement_transform(aip.getTransform());
76 globals->get_scenery()->get_scene_graph()->removeKid(aip.getSceneGraph());
79 SGPropertyNode* parent = props->getParent();
81 fgSetString("/ai/models/model-removed", props->getPath());
82 parent->removeChild(props->getName(), props->getIndex(), false);
90 void FGAIBase::readFromScenario(SGPropertyNode* scFileNode)
95 setPath(scFileNode->getStringValue("model", "Models/Geometry/glider.ac"));
97 setHeading(scFileNode->getDoubleValue("heading", 0.0));
98 setSpeed(scFileNode->getDoubleValue("speed", 0.0));
99 setAltitude(scFileNode->getDoubleValue("altitude", 0.0));
100 setLongitude(scFileNode->getDoubleValue("longitude", 0.0));
101 setLatitude(scFileNode->getDoubleValue("latitude", 0.0));
102 setBank(scFileNode->getDoubleValue("roll", 0.0));
105 void FGAIBase::update(double dt) {
106 if (_otype == otStatic)
108 if (_otype == otBallistic)
111 ft_per_deg_lat = 366468.96 - 3717.12 * cos(pos.getLatitudeRad());
112 ft_per_deg_lon = 365228.16 * cos(pos.getLatitudeRad());
115 void FGAIBase::Transform() {
117 aip.setPosition(pos);
119 aip.setOrientation(0.0, pitch, hdg);
121 aip.setOrientation(roll, pitch, hdg);
128 bool FGAIBase::init() {
130 if (!model_path.empty()) {
132 model = load3DModel( globals->get_fg_root(), model_path, props,
133 globals->get_sim_time_sec() );
134 } catch (const sg_exception &e) {
140 aip.setVisible(true);
142 globals->get_scenery()->get_scene_graph()->addKid(aip.getSceneGraph());
143 // Register that one at the scenery manager
144 globals->get_scenery()->register_placement_transform(aip.getTransform());
145 fgSetString("/ai/models/model-added", props->getPath());
147 if (!model_path.empty()) {
148 SG_LOG(SG_INPUT, SG_WARN, "AIBase: Could not load model " << model_path);
158 ssgBranch * FGAIBase::load3DModel(const string& fg_root,
160 SGPropertyNode *prop_root,
163 // some more code here to check whether a model with this name has already been loaded
164 // if not load it, otherwise, get the memory pointer and do something like
165 // SetModel as in ATC/AIEntity.cxx
166 ssgBranch *personality_branch = new SGPersonalityBranch;
168 model = manager->getModel(path);
170 model = sgLoad3DModel(fg_root,
174 manager->setModel(path, model);
176 personality_branch->addKid( model );
178 return personality_branch;
181 bool FGAIBase::isa( object_type otype ) {
182 if ( otype == _otype )
189 void FGAIBase::bind() {
190 props->tie("id", SGRawValueMethods<FGAIBase,int>(*this,
192 props->tie("velocities/true-airspeed-kt", SGRawValuePointer<double>(&speed));
193 props->tie("velocities/vertical-speed-fps",
194 SGRawValueMethods<FGAIBase,double>(*this,
195 &FGAIBase::_getVS_fps,
196 &FGAIBase::_setVS_fps));
198 props->tie("position/altitude-ft",
199 SGRawValueMethods<FGAIBase,double>(*this,
200 &FGAIBase::_getAltitude,
201 &FGAIBase::_setAltitude));
202 props->tie("position/latitude-deg",
203 SGRawValueMethods<FGAIBase,double>(*this,
204 &FGAIBase::_getLatitude,
205 &FGAIBase::_setLatitude));
206 props->tie("position/longitude-deg",
207 SGRawValueMethods<FGAIBase,double>(*this,
208 &FGAIBase::_getLongitude,
209 &FGAIBase::_setLongitude));
211 props->tie("orientation/pitch-deg", SGRawValuePointer<double>(&pitch));
212 props->tie("orientation/roll-deg", SGRawValuePointer<double>(&roll));
213 props->tie("orientation/true-heading-deg", SGRawValuePointer<double>(&hdg));
215 props->tie("radar/in-range", SGRawValuePointer<bool>(&in_range));
216 props->tie("radar/bearing-deg", SGRawValuePointer<double>(&bearing));
217 props->tie("radar/elevation-deg", SGRawValuePointer<double>(&elevation));
218 props->tie("radar/range-nm", SGRawValuePointer<double>(&range));
219 props->tie("radar/h-offset", SGRawValuePointer<double>(&horiz_offset));
220 props->tie("radar/v-offset", SGRawValuePointer<double>(&vert_offset));
221 props->tie("radar/x-shift", SGRawValuePointer<double>(&x_shift));
222 props->tie("radar/y-shift", SGRawValuePointer<double>(&y_shift));
223 props->tie("radar/rotation", SGRawValuePointer<double>(&rotation));
224 props->tie("radar/ht-diff-ft", SGRawValuePointer<double>(&ht_diff));
226 props->tie("controls/lighting/nav-lights",
227 SGRawValueFunctions<bool>(_isNight));
228 props->setBoolValue("controls/lighting/beacon", true);
229 props->setBoolValue("controls/lighting/strobe", true);
230 props->setBoolValue("controls/glide-path", true);
232 props->setStringValue("controls/flight/lateral-mode", "roll");
233 props->setDoubleValue("controls/flight/target-hdg", hdg);
234 props->setDoubleValue("controls/flight/target-roll", roll);
236 props->setStringValue("controls/flight/longitude-mode", "alt");
237 props->setDoubleValue("controls/flight/target-alt", altitude_ft);
238 props->setDoubleValue("controls/flight/target-pitch", pitch);
240 props->setDoubleValue("controls/flight/target-spd", speed);
244 void FGAIBase::unbind() {
246 props->untie("velocities/true-airspeed-kt");
247 props->untie("velocities/vertical-speed-fps");
249 props->untie("position/altitude-ft");
250 props->untie("position/latitude-deg");
251 props->untie("position/longitude-deg");
253 props->untie("orientation/pitch-deg");
254 props->untie("orientation/roll-deg");
255 props->untie("orientation/true-heading-deg");
257 props->untie("radar/in-range");
258 props->untie("radar/bearing-deg");
259 props->untie("radar/elevation-deg");
260 props->untie("radar/range-nm");
261 props->untie("radar/h-offset");
262 props->untie("radar/v-offset");
263 props->untie("radar/x-shift");
264 props->untie("radar/y-shift");
265 props->untie("radar/rotation");
266 props->untie("radar/ht-diff-ft");
268 props->untie("controls/lighting/nav-lights");
271 double FGAIBase::UpdateRadar(FGAIManager* manager)
273 double radar_range_ft2 = fgGetDouble("/instrumentation/radar/range");
274 bool force_on = fgGetBool("/instrumentation/radar/debug-mode", false);
275 radar_range_ft2 *= SG_NM_TO_METER * SG_METER_TO_FEET * 1.1; // + 10%
276 radar_range_ft2 *= radar_range_ft2;
278 double user_latitude = manager->get_user_latitude();
279 double user_longitude = manager->get_user_longitude();
280 double lat_range = fabs(pos.getLatitudeDeg() - user_latitude) * ft_per_deg_lat;
281 double lon_range = fabs(pos.getLongitudeDeg() - user_longitude) * ft_per_deg_lon;
282 double range_ft2 = lat_range*lat_range + lon_range*lon_range;
285 // Test whether the target is within radar range.
287 in_range = (range_ft2 && (range_ft2 <= radar_range_ft2));
288 if ( in_range || force_on )
290 props->setBoolValue("radar/in-range", true);
292 // copy values from the AIManager
293 double user_altitude = manager->get_user_altitude();
294 double user_heading = manager->get_user_heading();
295 double user_pitch = manager->get_user_pitch();
296 //double user_yaw = manager->get_user_yaw();
297 //double user_speed = manager->get_user_speed();
299 // calculate range to target in feet and nautical miles
300 double range_ft = sqrt( range_ft2 );
301 range = range_ft / 6076.11549;
303 // calculate bearing to target
304 if (pos.getLatitudeDeg() >= user_latitude) {
305 bearing = atan2(lat_range, lon_range) * SG_RADIANS_TO_DEGREES;
306 if (pos.getLongitudeDeg() >= user_longitude) {
307 bearing = 90.0 - bearing;
309 bearing = 270.0 + bearing;
312 bearing = atan2(lon_range, lat_range) * SG_RADIANS_TO_DEGREES;
313 if (pos.getLongitudeDeg() >= user_longitude) {
314 bearing = 180.0 - bearing;
316 bearing = 180.0 + bearing;
320 // This is an alternate way to compute bearing and distance which
321 // agrees with the original scheme within about 0.1 degrees.
323 // Point3D start( user_longitude * SGD_DEGREES_TO_RADIANS,
324 // user_latitude * SGD_DEGREES_TO_RADIANS, 0 );
325 // Point3D dest( pos.getLongitudeRad(), pos.getLatitudeRad(), 0 );
326 // double gc_bearing, gc_range;
327 // calc_gc_course_dist( start, dest, &gc_bearing, &gc_range );
328 // gc_range *= SG_METER_TO_NM;
329 // gc_bearing *= SGD_RADIANS_TO_DEGREES;
330 // printf("orig b = %.3f %.2f gc b= %.3f, %.2f\n",
331 // bearing, range, gc_bearing, gc_range);
333 // calculate look left/right to target, without yaw correction
334 horiz_offset = bearing - user_heading;
335 if (horiz_offset > 180.0) horiz_offset -= 360.0;
336 if (horiz_offset < -180.0) horiz_offset += 360.0;
338 // calculate elevation to target
339 elevation = atan2( altitude_ft - user_altitude, range_ft ) * SG_RADIANS_TO_DEGREES;
341 // calculate look up/down to target
342 vert_offset = elevation - user_pitch;
344 /* this calculation needs to be fixed, but it isn't important anyway
345 // calculate range rate
346 double recip_bearing = bearing + 180.0;
347 if (recip_bearing > 360.0) recip_bearing -= 360.0;
348 double my_horiz_offset = recip_bearing - hdg;
349 if (my_horiz_offset > 180.0) my_horiz_offset -= 360.0;
350 if (my_horiz_offset < -180.0) my_horiz_offset += 360.0;
351 rdot = (-user_speed * cos( horiz_offset * SG_DEGREES_TO_RADIANS ))
352 +(-speed * 1.686 * cos( my_horiz_offset * SG_DEGREES_TO_RADIANS ));
355 // now correct look left/right for yaw
356 // horiz_offset += user_yaw; // FIXME: WHY WOULD WE WANT TO ADD IN SIDE-SLIP HERE?
358 // calculate values for radar display
359 y_shift = range * cos( horiz_offset * SG_DEGREES_TO_RADIANS);
360 x_shift = range * sin( horiz_offset * SG_DEGREES_TO_RADIANS);
361 rotation = hdg - user_heading;
362 if (rotation < 0.0) rotation += 360.0;
363 ht_diff = altitude_ft - user_altitude;
371 FGAIBase::getCartPosAt(const SGVec3d& _off) const
373 // Transform that one to the horizontal local coordinate system.
375 SGQuatd hlTrans = SGQuatd::fromLonLat(pos);
376 // and postrotate the orientation of the AIModel wrt the horizontal
378 hlTrans *= SGQuatd::fromYawPitchRollDeg(hdg, pitch, roll);
380 // The offset converted to the usual body fixed coordinate system
381 // rotated to the earth fiexed coordinates axis
382 SGVec3d off = hlTrans.backTransform(_off);
384 // Add the position offset of the AIModel to gain the earth centered position
385 SGVec3d cartPos = SGVec3d::fromGeod(pos);
387 return cartPos + off;
391 * getters and Setters
393 void FGAIBase::_setLongitude( double longitude ) {
394 pos.setLongitudeDeg(longitude);
396 void FGAIBase::_setLatitude ( double latitude ) {
397 pos.setLatitudeDeg(latitude);
400 double FGAIBase::_getLongitude() const {
401 return pos.getLongitudeDeg();
403 double FGAIBase::_getLatitude () const {
404 return pos.getLatitudeDeg();
406 double FGAIBase::_getRdot() const {
409 double FGAIBase::_getVS_fps() const {
412 void FGAIBase::_setVS_fps( double _vs ) {
416 double FGAIBase::_getAltitude() const {
419 void FGAIBase::_setAltitude( double _alt ) {
423 bool FGAIBase::_isNight() {
424 return (fgGetFloat("/sim/time/sun-angle-rad") > 1.57);
427 int FGAIBase::getID() const {
431 void FGAIBase::CalculateMach() {
432 // Calculate rho at altitude, using standard atmosphere
433 // For the temperature T and the pressure p,
435 double altitude = altitude_ft;
437 if (altitude < 36152) { // curve fits for the troposphere
438 T = 59 - 0.00356 * altitude;
439 p = 2116 * pow( ((T + 459.7) / 518.6) , 5.256);
441 } else if ( 36152 < altitude && altitude < 82345 ) { // lower stratosphere
443 p = 473.1 * pow( e , 1.73 - (0.000048 * altitude) );
445 } else { // upper stratosphere
446 T = -205.05 + (0.00164 * altitude);
447 p = 51.97 * pow( ((T + 459.7) / 389.98) , -11.388);
450 rho = p / (1718 * (T + 459.7));
452 // calculate the speed of sound at altitude
453 // a = sqrt ( g * R * (T + 459.7))
455 // a = speed of sound [ft/s]
456 // g = specific heat ratio, which is usually equal to 1.4
457 // R = specific gas constant, which equals 1716 ft-lb/slug/°R
459 a = sqrt ( 1.4 * 1716 * (T + 459.7));
461 // calculate Mach number
465 // cout << "Speed(ft/s) "<< speed <<" Altitude(ft) "<< altitude << " Mach " << Mach;
468 int FGAIBase::_newAIModelID() {
471 id++; // id = 0 is not allowed.