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 globals->get_scenery()->get_scene_graph()->removeKid(aip.getSceneGraph());
74 SGPropertyNode *root = globals->get_props()->getNode("ai/models", true);
75 root->removeChild(_type_str.c_str(), index);
80 void FGAIBase::update(double dt) {
81 ft_per_deg_lat = 366468.96 - 3717.12 * cos(pos.lat()/SG_RADIANS_TO_DEGREES);
82 ft_per_deg_lon = 365228.16 * cos(pos.lat() / SG_RADIANS_TO_DEGREES);
84 // Calculate rho at altitude, using standard atmosphere
85 // For the temperature T and the pressure p,
87 if (altitude < 36152) { // curve fits for the troposphere
88 T = 59 - 0.00356 * altitude;
89 p = 2116 * pow( ((T + 459.7) / 518.6) , 5.256);
91 } else if ( 36152 < altitude < 82345 ) { // lower stratosphere
93 p = 473.1 * pow( e , 1.73 - (0.000048 * altitude) );
95 } else { // upper stratosphere
96 T = -205.05 + (0.00164 * altitude);
97 p = 51.97 * pow( ((T + 459.7) / 389.98) , -11.388);
100 rho = p / (1718 * (T + 459.7));
104 void FGAIBase::Transform() {
106 aip.setPosition(pos.lon(), pos.lat(), pos.elev() * SG_METER_TO_FEET);
108 aip.setOrientation(0.0, pitch, hdg);
110 aip.setOrientation(roll, pitch, hdg);
112 aip.update( globals->get_scenery()->get_center() );
117 bool FGAIBase::init() {
119 SGPropertyNode *root = globals->get_props()->getNode("ai/models", true);
121 index = manager->getNum(_otype) - 1;
122 props = root->getNode(_type_str.c_str(), index, true);
124 if (model_path != "") {
125 model = sgLoad3DModel( globals->get_fg_root(),
128 globals->get_sim_time_sec() );
132 aip.setVisible(true);
134 globals->get_scenery()->get_scene_graph()->addKid(aip.getSceneGraph());
136 if (model_path != "") {
137 SG_LOG(SG_INPUT, SG_WARN, "AIBase: Could not load model.");
146 bool FGAIBase::isa( object_type otype ) {
147 if ( otype == _otype ) { return true; }
148 else { return false; }
152 void FGAIBase::bind() {
153 props->tie("id", SGRawValueMethods<FGAIBase,int>(*this,
155 props->tie("velocities/true-airspeed-kt", SGRawValuePointer<double>(&speed));
156 props->tie("velocities/vertical-speed-fps",
157 SGRawValueMethods<FGAIBase,double>(*this,
158 &FGAIBase::_getVS_fps,
159 &FGAIBase::_setVS_fps));
161 props->tie("position/altitude-ft",
162 SGRawValueMethods<FGAIBase,double>(*this,
163 &FGAIBase::_getAltitude,
164 &FGAIBase::_setAltitude));
165 props->tie("position/latitude-deg",
166 SGRawValueMethods<FGAIBase,double>(*this,
167 &FGAIBase::_getLatitude,
168 &FGAIBase::_setLatitude));
169 props->tie("position/longitude-deg",
170 SGRawValueMethods<FGAIBase,double>(*this,
171 &FGAIBase::_getLongitude,
172 &FGAIBase::_setLongitude));
174 props->tie("orientation/pitch-deg", SGRawValuePointer<double>(&pitch));
175 props->tie("orientation/roll-deg", SGRawValuePointer<double>(&roll));
176 props->tie("orientation/true-heading-deg", SGRawValuePointer<double>(&hdg));
178 props->tie("radar/in-range", SGRawValuePointer<bool>(&in_range));
179 props->tie("radar/bearing-deg", SGRawValuePointer<double>(&bearing));
180 props->tie("radar/elevation-deg", SGRawValuePointer<double>(&elevation));
181 props->tie("radar/range-nm", SGRawValuePointer<double>(&range));
182 props->tie("radar/h-offset", SGRawValuePointer<double>(&horiz_offset));
183 props->tie("radar/v-offset", SGRawValuePointer<double>(&vert_offset));
184 props->tie("radar/x-shift", SGRawValuePointer<double>(&x_shift));
185 props->tie("radar/y-shift", SGRawValuePointer<double>(&y_shift));
186 props->tie("radar/rotation", SGRawValuePointer<double>(&rotation));
188 props->tie("controls/lighting/nav-lights",
189 SGRawValueFunctions<bool>(_isNight));
190 props->setBoolValue("controls/lighting/beacon", true);
191 props->setBoolValue("controls/lighting/strobe", true);
194 void FGAIBase::unbind() {
196 props->untie("velocities/true-airspeed-kt");
197 props->untie("velocities/vertical-speed-fps");
199 props->untie("position/altitude-ft");
200 props->untie("position/latitude-deg");
201 props->untie("position/longitude-deg");
203 props->untie("orientation/pitch-deg");
204 props->untie("orientation/roll-deg");
205 props->untie("orientation/true-heading-deg");
207 props->untie("radar/in-range");
208 props->untie("radar/bearing-deg");
209 props->untie("radar/elevation-deg");
210 props->untie("radar/range-nm");
211 props->untie("radar/h-offset");
212 props->untie("radar/v-offset");
213 props->untie("radar/x-shift");
214 props->untie("radar/y-shift");
215 props->untie("radar/rotation");
217 props->untie("controls/lighting/nav-lights");
220 double FGAIBase::UpdateRadar(FGAIManager* manager)
222 double radar_range_ft2 = fgGetDouble("/instrumentation/radar/range");
223 radar_range_ft2 *= SG_NM_TO_METER * SG_METER_TO_FEET * 1.1; // + 10%
224 radar_range_ft2 *= radar_range_ft2;
226 double user_latitude = manager->get_user_latitude();
227 double user_longitude = manager->get_user_longitude();
228 double lat_range = fabs(pos.lat() - user_latitude) * ft_per_deg_lat;
229 double lon_range = fabs(pos.lon() - user_longitude) * ft_per_deg_lon;
230 double range_ft2 = lat_range*lat_range + lon_range*lon_range;
233 // Test whether the target is within radar range.
235 in_range = (range_ft2 && (range_ft2 <= radar_range_ft2));
238 props->setBoolValue("radar/in-range", true);
240 // copy values from the AIManager
241 double user_altitude = manager->get_user_altitude();
242 double user_heading = manager->get_user_heading();
243 double user_pitch = manager->get_user_pitch();
244 double user_yaw = manager->get_user_yaw();
245 double user_speed = manager->get_user_speed();
247 // calculate range to target in feet and nautical miles
248 double range_ft = sqrt( range_ft2 );
249 range = range_ft / 6076.11549;
251 // calculate bearing to target
252 if (pos.lat() >= user_latitude) {
253 bearing = atan2(lat_range, lon_range) * SG_RADIANS_TO_DEGREES;
254 if (pos.lon() >= user_longitude) {
255 bearing = 90.0 - bearing;
257 bearing = 270.0 + bearing;
260 bearing = atan2(lon_range, lat_range) * SG_RADIANS_TO_DEGREES;
261 if (pos.lon() >= user_longitude) {
262 bearing = 180.0 - bearing;
264 bearing = 180.0 + bearing;
268 // calculate look left/right to target, without yaw correction
269 horiz_offset = bearing - user_heading;
270 if (horiz_offset > 180.0) horiz_offset -= 360.0;
271 if (horiz_offset < -180.0) horiz_offset += 360.0;
273 // calculate elevation to target
274 elevation = atan2( altitude * SG_METER_TO_FEET - user_altitude, range_ft )
275 * SG_RADIANS_TO_DEGREES;
277 // calculate look up/down to target
278 vert_offset = elevation + user_pitch;
280 /* this calculation needs to be fixed, but it isn't important anyway
281 // calculate range rate
282 double recip_bearing = bearing + 180.0;
283 if (recip_bearing > 360.0) recip_bearing -= 360.0;
284 double my_horiz_offset = recip_bearing - hdg;
285 if (my_horiz_offset > 180.0) my_horiz_offset -= 360.0;
286 if (my_horiz_offset < -180.0) my_horiz_offset += 360.0;
287 rdot = (-user_speed * cos( horiz_offset * SG_DEGREES_TO_RADIANS ))
288 +(-speed * 1.686 * cos( my_horiz_offset * SG_DEGREES_TO_RADIANS ));
291 // now correct look left/right for yaw
292 horiz_offset += user_yaw;
294 // calculate values for radar display
295 y_shift = range * cos( horiz_offset * SG_DEGREES_TO_RADIANS);
296 x_shift = range * sin( horiz_offset * SG_DEGREES_TO_RADIANS);
297 rotation = hdg - user_heading;
298 if (rotation < 0.0) rotation += 360.0;
307 * getters and Setters
309 void FGAIBase::_setLongitude( double longitude ) {
310 pos.setlon(longitude);
312 void FGAIBase::_setLatitude ( double latitude ) {
313 pos.setlat(latitude);
316 double FGAIBase::_getLongitude() const {
319 double FGAIBase::_getLatitude () const {
322 double FGAIBase::_getRdot() const {
325 double FGAIBase::_getVS_fps() const {
328 void FGAIBase::_setVS_fps( double _vs ) {
332 double FGAIBase::_getAltitude() const {
335 void FGAIBase::_setAltitude( double _alt ) {
339 bool FGAIBase::_isNight() {
340 return (fgGetFloat("/sim/time/sun-angle-rad") > 1.57);
343 int FGAIBase::_getID() const {