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/debug/logstream.hxx>
39 #include <simgear/props/props.hxx>
41 #include <Main/globals.hxx>
42 #include <Scenery/scenery.hxx>
46 #include "AIManager.hxx"
49 const double FGAIBase::e = 2.71828183;
50 const double FGAIBase::lbs_to_slugs = 0.031080950172; //conversion factor
53 FGAIBase::FGAIBase(object_type ot)
57 _refID( _newAIModelID() ),
60 tgt_heading = hdg = tgt_altitude_ft = tgt_speed = 0.0;
61 tgt_roll = roll = tgt_pitch = tgt_yaw = tgt_vs = vs = pitch = 0.0;
62 bearing = elevation = range = rdot = 0.0;
63 x_shift = y_shift = rotation = 0.0;
71 FGAIBase::~FGAIBase() {
72 // Unregister that one at the scenery manager
73 if (globals->get_scenery()) {
74 globals->get_scenery()->unregister_placement_transform(aip.getTransform());
75 globals->get_scenery()->get_scene_graph()->removeKid(aip.getSceneGraph());
78 SGPropertyNode* parent = props->getParent();
80 fgSetString("/ai/models/model-removed", props->getPath());
81 parent->removeChild(props->getName(), props->getIndex(), false);
89 void FGAIBase::readFromScenario(SGPropertyNode* scFileNode)
94 setPath(scFileNode->getStringValue("model", "Models/Geometry/glider.ac"));
96 setHeading(scFileNode->getDoubleValue("heading", 0.0));
97 setSpeed(scFileNode->getDoubleValue("speed", 0.0));
98 setAltitude(scFileNode->getDoubleValue("altitude", 0.0));
99 setLongitude(scFileNode->getDoubleValue("longitude", 0.0));
100 setLatitude(scFileNode->getDoubleValue("latitude", 0.0));
101 setBank(scFileNode->getDoubleValue("roll", 0.0));
104 void FGAIBase::update(double dt) {
105 if (_otype == otStatic)
107 if (_otype == otBallistic)
110 ft_per_deg_lat = 366468.96 - 3717.12 * cos(pos.getLatitudeRad());
111 ft_per_deg_lon = 365228.16 * cos(pos.getLatitudeRad());
114 void FGAIBase::Transform() {
116 aip.setPosition(pos);
118 aip.setOrientation(0.0, pitch, hdg);
120 aip.setOrientation(roll, pitch, hdg);
127 bool FGAIBase::init() {
129 if (!model_path.empty()) {
131 model = load3DModel( globals->get_fg_root(), model_path, props,
132 globals->get_sim_time_sec() );
133 } catch (const sg_exception &e) {
139 aip.setVisible(true);
141 globals->get_scenery()->get_scene_graph()->addKid(aip.getSceneGraph());
142 // Register that one at the scenery manager
143 globals->get_scenery()->register_placement_transform(aip.getTransform());
144 fgSetString("/ai/models/model-added", props->getPath());
146 if (!model_path.empty()) {
147 SG_LOG(SG_INPUT, SG_WARN, "AIBase: Could not load model " << model_path);
157 ssgBranch * FGAIBase::load3DModel(const string& fg_root,
159 SGPropertyNode *prop_root,
162 // some more code here to check whether a model with this name has already been loaded
163 // if not load it, otherwise, get the memory pointer and do something like
164 // SetModel as in ATC/AIEntity.cxx
165 model = manager->getModel(path);
167 model = sgLoad3DModel(fg_root,
171 manager->setModel(path, model);
177 bool FGAIBase::isa( object_type otype ) {
178 if ( otype == _otype )
185 void FGAIBase::bind() {
186 props->tie("id", SGRawValueMethods<FGAIBase,int>(*this,
188 props->tie("velocities/true-airspeed-kt", SGRawValuePointer<double>(&speed));
189 props->tie("velocities/vertical-speed-fps",
190 SGRawValueMethods<FGAIBase,double>(*this,
191 &FGAIBase::_getVS_fps,
192 &FGAIBase::_setVS_fps));
194 props->tie("position/altitude-ft",
195 SGRawValueMethods<FGAIBase,double>(*this,
196 &FGAIBase::_getAltitude,
197 &FGAIBase::_setAltitude));
198 props->tie("position/latitude-deg",
199 SGRawValueMethods<FGAIBase,double>(*this,
200 &FGAIBase::_getLatitude,
201 &FGAIBase::_setLatitude));
202 props->tie("position/longitude-deg",
203 SGRawValueMethods<FGAIBase,double>(*this,
204 &FGAIBase::_getLongitude,
205 &FGAIBase::_setLongitude));
207 props->tie("orientation/pitch-deg", SGRawValuePointer<double>(&pitch));
208 props->tie("orientation/roll-deg", SGRawValuePointer<double>(&roll));
209 props->tie("orientation/true-heading-deg", SGRawValuePointer<double>(&hdg));
211 props->tie("radar/in-range", SGRawValuePointer<bool>(&in_range));
212 props->tie("radar/bearing-deg", SGRawValuePointer<double>(&bearing));
213 props->tie("radar/elevation-deg", SGRawValuePointer<double>(&elevation));
214 props->tie("radar/range-nm", SGRawValuePointer<double>(&range));
215 props->tie("radar/h-offset", SGRawValuePointer<double>(&horiz_offset));
216 props->tie("radar/v-offset", SGRawValuePointer<double>(&vert_offset));
217 props->tie("radar/x-shift", SGRawValuePointer<double>(&x_shift));
218 props->tie("radar/y-shift", SGRawValuePointer<double>(&y_shift));
219 props->tie("radar/rotation", SGRawValuePointer<double>(&rotation));
220 props->tie("radar/ht-diff-ft", SGRawValuePointer<double>(&ht_diff));
222 props->tie("controls/lighting/nav-lights",
223 SGRawValueFunctions<bool>(_isNight));
224 props->setBoolValue("controls/lighting/beacon", true);
225 props->setBoolValue("controls/lighting/strobe", true);
226 props->setBoolValue("controls/glide-path", true);
228 props->setStringValue("controls/flight/lateral-mode", "roll");
229 props->setDoubleValue("controls/flight/target-hdg", hdg);
230 props->setDoubleValue("controls/flight/target-roll", roll);
232 props->setStringValue("controls/flight/longitude-mode", "alt");
233 props->setDoubleValue("controls/flight/target-alt", altitude_ft);
234 props->setDoubleValue("controls/flight/target-pitch", pitch);
236 props->setDoubleValue("controls/flight/target-spd", speed);
240 void FGAIBase::unbind() {
242 props->untie("velocities/true-airspeed-kt");
243 props->untie("velocities/vertical-speed-fps");
245 props->untie("position/altitude-ft");
246 props->untie("position/latitude-deg");
247 props->untie("position/longitude-deg");
249 props->untie("orientation/pitch-deg");
250 props->untie("orientation/roll-deg");
251 props->untie("orientation/true-heading-deg");
253 props->untie("radar/in-range");
254 props->untie("radar/bearing-deg");
255 props->untie("radar/elevation-deg");
256 props->untie("radar/range-nm");
257 props->untie("radar/h-offset");
258 props->untie("radar/v-offset");
259 props->untie("radar/x-shift");
260 props->untie("radar/y-shift");
261 props->untie("radar/rotation");
262 props->untie("radar/ht-diff-ft");
264 props->untie("controls/lighting/nav-lights");
267 double FGAIBase::UpdateRadar(FGAIManager* manager)
269 double radar_range_ft2 = fgGetDouble("/instrumentation/radar/range");
270 bool force_on = fgGetBool("/instrumentation/radar/debug-mode", false);
271 radar_range_ft2 *= SG_NM_TO_METER * SG_METER_TO_FEET * 1.1; // + 10%
272 radar_range_ft2 *= radar_range_ft2;
274 double user_latitude = manager->get_user_latitude();
275 double user_longitude = manager->get_user_longitude();
276 double lat_range = fabs(pos.getLatitudeDeg() - user_latitude) * ft_per_deg_lat;
277 double lon_range = fabs(pos.getLongitudeDeg() - user_longitude) * ft_per_deg_lon;
278 double range_ft2 = lat_range*lat_range + lon_range*lon_range;
281 // Test whether the target is within radar range.
283 in_range = (range_ft2 && (range_ft2 <= radar_range_ft2));
284 if ( in_range || force_on )
286 props->setBoolValue("radar/in-range", true);
288 // copy values from the AIManager
289 double user_altitude = manager->get_user_altitude();
290 double user_heading = manager->get_user_heading();
291 double user_pitch = manager->get_user_pitch();
292 double user_yaw = manager->get_user_yaw();
293 double user_speed = manager->get_user_speed();
295 // calculate range to target in feet and nautical miles
296 double range_ft = sqrt( range_ft2 );
297 range = range_ft / 6076.11549;
299 // calculate bearing to target
300 if (pos.getLatitudeDeg() >= user_latitude) {
301 bearing = atan2(lat_range, lon_range) * SG_RADIANS_TO_DEGREES;
302 if (pos.getLongitudeDeg() >= user_longitude) {
303 bearing = 90.0 - bearing;
305 bearing = 270.0 + bearing;
308 bearing = atan2(lon_range, lat_range) * SG_RADIANS_TO_DEGREES;
309 if (pos.getLongitudeDeg() >= user_longitude) {
310 bearing = 180.0 - bearing;
312 bearing = 180.0 + bearing;
316 // This is an alternate way to compute bearing and distance which
317 // agrees with the original scheme within about 0.1 degrees.
319 // Point3D start( user_longitude * SGD_DEGREES_TO_RADIANS,
320 // user_latitude * SGD_DEGREES_TO_RADIANS, 0 );
321 // Point3D dest( pos.getLongitudeRad(), pos.getLatitudeRad(), 0 );
322 // double gc_bearing, gc_range;
323 // calc_gc_course_dist( start, dest, &gc_bearing, &gc_range );
324 // gc_range *= SG_METER_TO_NM;
325 // gc_bearing *= SGD_RADIANS_TO_DEGREES;
326 // printf("orig b = %.3f %.2f gc b= %.3f, %.2f\n",
327 // bearing, range, gc_bearing, gc_range);
329 // calculate look left/right to target, without yaw correction
330 horiz_offset = bearing - user_heading;
331 if (horiz_offset > 180.0) horiz_offset -= 360.0;
332 if (horiz_offset < -180.0) horiz_offset += 360.0;
334 // calculate elevation to target
335 elevation = atan2( altitude_ft - user_altitude, range_ft ) * SG_RADIANS_TO_DEGREES;
337 // calculate look up/down to target
338 vert_offset = elevation - user_pitch;
340 /* this calculation needs to be fixed, but it isn't important anyway
341 // calculate range rate
342 double recip_bearing = bearing + 180.0;
343 if (recip_bearing > 360.0) recip_bearing -= 360.0;
344 double my_horiz_offset = recip_bearing - hdg;
345 if (my_horiz_offset > 180.0) my_horiz_offset -= 360.0;
346 if (my_horiz_offset < -180.0) my_horiz_offset += 360.0;
347 rdot = (-user_speed * cos( horiz_offset * SG_DEGREES_TO_RADIANS ))
348 +(-speed * 1.686 * cos( my_horiz_offset * SG_DEGREES_TO_RADIANS ));
351 // now correct look left/right for yaw
352 // horiz_offset += user_yaw; // FIXME: WHY WOULD WE WANT TO ADD IN SIDE-SLIP HERE?
354 // calculate values for radar display
355 y_shift = range * cos( horiz_offset * SG_DEGREES_TO_RADIANS);
356 x_shift = range * sin( horiz_offset * SG_DEGREES_TO_RADIANS);
357 rotation = hdg - user_heading;
358 if (rotation < 0.0) rotation += 360.0;
359 ht_diff = altitude_ft - user_altitude;
367 FGAIBase::getCartPosAt(const SGVec3d& _off) const
369 // Transform that one to the horizontal local coordinate system.
371 SGQuatd hlTrans = SGQuatd::fromLonLat(pos);
372 // and postrotate the orientation of the AIModel wrt the horizontal
374 hlTrans *= SGQuatd::fromYawPitchRollDeg(hdg, pitch, roll);
376 // The offset converted to the usual body fixed coordinate system
377 // rotated to the earth fiexed coordinates axis
378 SGVec3d off = hlTrans.backTransform(_off);
380 // Add the position offset of the AIModel to gain the earth centered position
381 SGVec3d cartPos = SGVec3d::fromGeod(pos);
383 return cartPos + off;
387 * getters and Setters
389 void FGAIBase::_setLongitude( double longitude ) {
390 pos.setLongitudeDeg(longitude);
392 void FGAIBase::_setLatitude ( double latitude ) {
393 pos.setLatitudeDeg(latitude);
396 double FGAIBase::_getLongitude() const {
397 return pos.getLongitudeDeg();
399 double FGAIBase::_getLatitude () const {
400 return pos.getLatitudeDeg();
402 double FGAIBase::_getRdot() const {
405 double FGAIBase::_getVS_fps() const {
408 void FGAIBase::_setVS_fps( double _vs ) {
412 double FGAIBase::_getAltitude() const {
415 void FGAIBase::_setAltitude( double _alt ) {
419 bool FGAIBase::_isNight() {
420 return (fgGetFloat("/sim/time/sun-angle-rad") > 1.57);
423 int FGAIBase::getID() const {
427 void FGAIBase::CalculateMach() {
428 // Calculate rho at altitude, using standard atmosphere
429 // For the temperature T and the pressure p,
431 double altitude = altitude_ft;
433 if (altitude < 36152) { // curve fits for the troposphere
434 T = 59 - 0.00356 * altitude;
435 p = 2116 * pow( ((T + 459.7) / 518.6) , 5.256);
437 } else if ( 36152 < altitude && altitude < 82345 ) { // lower stratosphere
439 p = 473.1 * pow( e , 1.73 - (0.000048 * altitude) );
441 } else { // upper stratosphere
442 T = -205.05 + (0.00164 * altitude);
443 p = 51.97 * pow( ((T + 459.7) / 389.98) , -11.388);
446 rho = p / (1718 * (T + 459.7));
448 // calculate the speed of sound at altitude
449 // a = sqrt ( g * R * (T + 459.7))
451 // a = speed of sound [ft/s]
452 // g = specific heat ratio, which is usually equal to 1.4
453 // R = specific gas constant, which equals 1716 ft-lb/slug/°R
455 a = sqrt ( 1.4 * 1716 * (T + 459.7));
457 // calculate Mach number
461 // cout << "Speed(ft/s) "<< speed <<" Altitude(ft) "<< altitude << " Mach " << Mach;
464 int FGAIBase::_newAIModelID() {
467 id++; // id = 0 is not allowed.