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., 675 Mass Ave, Cambridge, MA 02139, USA.
25 #include <simgear/compiler.h>
32 #include <simgear/math/point3d.hxx>
33 #include <simgear/misc/sg_path.hxx>
34 #include <simgear/scene/model/location.hxx>
35 #include <simgear/scene/model/model.hxx>
36 #include <simgear/debug/logstream.hxx>
37 #include <simgear/props/props.hxx>
39 #include <Main/globals.hxx>
40 #include <Scenery/scenery.hxx>
44 #include "AIManager.hxx"
47 const double FGAIBase::e = 2.71828183;
48 const double FGAIBase::lbs_to_slugs = 0.031080950172; //conversion factor
58 tgt_roll = roll = tgt_pitch = tgt_yaw = tgt_vs = vs = pitch = 0.0;
59 bearing = elevation = range = rdot = 0.0;
60 x_shift = y_shift = rotation = 0.0;
71 FGAIBase::~FGAIBase() {
72 // Unregister that one at the scenery manager
73 globals->get_scenery()->unregister_placement_transform(aip.getTransform());
75 globals->get_scenery()->get_scene_graph()->removeKid(aip.getSceneGraph());
77 SGPropertyNode *root = globals->get_props()->getNode("ai/models", true);
78 root->removeChild(_type_str.c_str(), index);
83 void FGAIBase::update(double dt) {
84 ft_per_deg_lat = 366468.96 - 3717.12 * cos(pos.lat()*SGD_DEGREES_TO_RADIANS);
85 ft_per_deg_lon = 365228.16 * cos(pos.lat()*SGD_DEGREES_TO_RADIANS);
87 // Calculate rho at altitude, using standard atmosphere
88 // For the temperature T and the pressure p,
90 if (altitude < 36152) { // curve fits for the troposphere
91 T = 59 - 0.00356 * altitude;
92 p = 2116 * pow( ((T + 459.7) / 518.6) , 5.256);
94 } else if ( 36152 < altitude && altitude < 82345 ) { // lower stratosphere
96 p = 473.1 * pow( e , 1.73 - (0.000048 * altitude) );
98 } else { // upper stratosphere
99 T = -205.05 + (0.00164 * altitude);
100 p = 51.97 * pow( ((T + 459.7) / 389.98) , -11.388);
103 rho = p / (1718 * (T + 459.7));
105 // calculate the speed of sound at altitude
106 // a = sqrt ( g * R * (T + 459.7))
108 // a = speed of sound [ft/s]
109 // g = specific heat ratio, which is usually equal to 1.4
110 // R = specific gas constant, which equals 1716 ft-lb/slug/°R
112 a = sqrt ( 1.4 * 1716 * (T + 459.7));
114 // calculate Mach number
118 // cout << "Speed(ft/s) "<< speed <<" Altitude(ft) "<< altitude << " Mach " << Mach;
121 void FGAIBase::Transform() {
123 aip.setPosition(pos.lon(), pos.lat(), pos.elev() * SG_METER_TO_FEET);
125 aip.setOrientation(0.0, pitch, hdg);
127 aip.setOrientation(roll, pitch, hdg);
129 aip.update( globals->get_scenery()->get_center() );
134 bool FGAIBase::init() {
136 SGPropertyNode *root = globals->get_props()->getNode("ai/models", true);
138 index = manager->getNum(_otype) - 1;
139 props = root->getNode(_type_str.c_str(), index, true);
141 if (model_path != "") {
142 model = load3DModel( globals->get_fg_root(),
143 SGPath(model_path).c_str(),
145 globals->get_sim_time_sec() );
149 aip.setVisible(true);
151 globals->get_scenery()->get_scene_graph()->addKid(aip.getSceneGraph());
152 // Register that one at the scenery manager
153 globals->get_scenery()->register_placement_transform(aip.getTransform());
155 if (model_path != "") {
156 SG_LOG(SG_INPUT, SG_WARN, "AIBase: Could not load model.");
166 ssgBranch * FGAIBase::load3DModel(const string& fg_root,
168 SGPropertyNode *prop_root,
171 // some more code here to check whether a model with this name has already been loaded
172 // if not load it, otherwise, get the memory pointer and do something like
173 // SetModel as in ATC/AIEntity.cxx
175 model = manager->getModel(path);
178 model = sgLoad3DModel(fg_root,
182 manager->setModel(path, model);
189 // aip.setVisible(false);
190 // globals->get_scenery()->get_scene_graph()->addKid(aip.getSceneGraph());
191 // do some setModel stuff.
195 bool FGAIBase::isa( object_type otype ) {
196 if ( otype == _otype ) { return true; }
197 else { return false; }
201 void FGAIBase::bind() {
202 props->tie("id", SGRawValueMethods<FGAIBase,int>(*this,
204 props->tie("velocities/true-airspeed-kt", SGRawValuePointer<double>(&speed));
205 props->tie("velocities/vertical-speed-fps",
206 SGRawValueMethods<FGAIBase,double>(*this,
207 &FGAIBase::_getVS_fps,
208 &FGAIBase::_setVS_fps));
210 props->tie("position/altitude-ft",
211 SGRawValueMethods<FGAIBase,double>(*this,
212 &FGAIBase::_getAltitude,
213 &FGAIBase::_setAltitude));
214 props->tie("position/latitude-deg",
215 SGRawValueMethods<FGAIBase,double>(*this,
216 &FGAIBase::_getLatitude,
217 &FGAIBase::_setLatitude));
218 props->tie("position/longitude-deg",
219 SGRawValueMethods<FGAIBase,double>(*this,
220 &FGAIBase::_getLongitude,
221 &FGAIBase::_setLongitude));
223 props->tie("orientation/pitch-deg", SGRawValuePointer<double>(&pitch));
224 props->tie("orientation/roll-deg", SGRawValuePointer<double>(&roll));
225 props->tie("orientation/true-heading-deg", SGRawValuePointer<double>(&hdg));
227 props->tie("radar/in-range", SGRawValuePointer<bool>(&in_range));
228 props->tie("radar/bearing-deg", SGRawValuePointer<double>(&bearing));
229 props->tie("radar/elevation-deg", SGRawValuePointer<double>(&elevation));
230 props->tie("radar/range-nm", SGRawValuePointer<double>(&range));
231 props->tie("radar/h-offset", SGRawValuePointer<double>(&horiz_offset));
232 props->tie("radar/v-offset", SGRawValuePointer<double>(&vert_offset));
233 props->tie("radar/x-shift", SGRawValuePointer<double>(&x_shift));
234 props->tie("radar/y-shift", SGRawValuePointer<double>(&y_shift));
235 props->tie("radar/rotation", SGRawValuePointer<double>(&rotation));
237 props->tie("controls/lighting/nav-lights",
238 SGRawValueFunctions<bool>(_isNight));
239 props->setBoolValue("controls/lighting/beacon", true);
240 props->setBoolValue("controls/lighting/strobe", true);
241 props->setBoolValue("controls/glide-path", true);
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");
267 props->untie("controls/lighting/nav-lights");
270 double FGAIBase::UpdateRadar(FGAIManager* manager)
272 double radar_range_ft2 = fgGetDouble("/instrumentation/radar/range");
273 radar_range_ft2 *= SG_NM_TO_METER * SG_METER_TO_FEET * 1.1; // + 10%
274 radar_range_ft2 *= radar_range_ft2;
276 double user_latitude = manager->get_user_latitude();
277 double user_longitude = manager->get_user_longitude();
278 double lat_range = fabs(pos.lat() - user_latitude) * ft_per_deg_lat;
279 double lon_range = fabs(pos.lon() - user_longitude) * ft_per_deg_lon;
280 double range_ft2 = lat_range*lat_range + lon_range*lon_range;
283 // Test whether the target is within radar range.
285 in_range = (range_ft2 && (range_ft2 <= radar_range_ft2));
288 props->setBoolValue("radar/in-range", true);
290 // copy values from the AIManager
291 double user_altitude = manager->get_user_altitude();
292 double user_heading = manager->get_user_heading();
293 double user_pitch = manager->get_user_pitch();
294 double user_yaw = manager->get_user_yaw();
295 double user_speed = manager->get_user_speed();
297 // calculate range to target in feet and nautical miles
298 double range_ft = sqrt( range_ft2 );
299 range = range_ft / 6076.11549;
301 // calculate bearing to target
302 if (pos.lat() >= user_latitude) {
303 bearing = atan2(lat_range, lon_range) * SG_RADIANS_TO_DEGREES;
304 if (pos.lon() >= user_longitude) {
305 bearing = 90.0 - bearing;
307 bearing = 270.0 + bearing;
310 bearing = atan2(lon_range, lat_range) * SG_RADIANS_TO_DEGREES;
311 if (pos.lon() >= user_longitude) {
312 bearing = 180.0 - bearing;
314 bearing = 180.0 + bearing;
318 // calculate look left/right to target, without yaw correction
319 horiz_offset = bearing - user_heading;
320 if (horiz_offset > 180.0) horiz_offset -= 360.0;
321 if (horiz_offset < -180.0) horiz_offset += 360.0;
323 // calculate elevation to target
324 elevation = atan2( altitude * SG_METER_TO_FEET - user_altitude, range_ft )
325 * SG_RADIANS_TO_DEGREES;
327 // calculate look up/down to target
328 vert_offset = elevation + user_pitch;
330 /* this calculation needs to be fixed, but it isn't important anyway
331 // calculate range rate
332 double recip_bearing = bearing + 180.0;
333 if (recip_bearing > 360.0) recip_bearing -= 360.0;
334 double my_horiz_offset = recip_bearing - hdg;
335 if (my_horiz_offset > 180.0) my_horiz_offset -= 360.0;
336 if (my_horiz_offset < -180.0) my_horiz_offset += 360.0;
337 rdot = (-user_speed * cos( horiz_offset * SG_DEGREES_TO_RADIANS ))
338 +(-speed * 1.686 * cos( my_horiz_offset * SG_DEGREES_TO_RADIANS ));
341 // now correct look left/right for yaw
342 horiz_offset += user_yaw;
344 // calculate values for radar display
345 y_shift = range * cos( horiz_offset * SG_DEGREES_TO_RADIANS);
346 x_shift = range * sin( horiz_offset * SG_DEGREES_TO_RADIANS);
347 rotation = hdg - user_heading;
348 if (rotation < 0.0) rotation += 360.0;
357 * getters and Setters
359 void FGAIBase::_setLongitude( double longitude ) {
360 pos.setlon(longitude);
362 void FGAIBase::_setLatitude ( double latitude ) {
363 pos.setlat(latitude);
366 double FGAIBase::_getLongitude() const {
369 double FGAIBase::_getLatitude () const {
372 double FGAIBase::_getRdot() const {
375 double FGAIBase::_getVS_fps() const {
378 void FGAIBase::_setVS_fps( double _vs ) {
382 double FGAIBase::_getAltitude() const {
385 void FGAIBase::_setAltitude( double _alt ) {
389 bool FGAIBase::_isNight() {
390 return (fgGetFloat("/sim/time/sun-angle-rad") > 1.57);
393 int FGAIBase::_getID() const {