1 // Wx Radar background texture
3 // Written by Harald JOHNSEN, started May 2005.
4 // With major amendments by Vivian MEAZZA May 2007
5 // Ported to OSG by Tim Moore Jun 2007
8 // Copyright (C) 2005 Harald JOHNSEN
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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
31 #include <osg/Geometry>
32 #include <osg/Matrixf>
33 #include <osg/PrimitiveSet>
34 #include <osg/StateSet>
35 #include <osgDB/WriteFile>
37 #include <simgear/constants.h>
38 #include <simgear/misc/sg_path.hxx>
39 #include <simgear/environment/visual_enviro.hxx>
40 #include <simgear/scene/model/model.hxx>
41 #include <simgear/structure/exception.hxx>
42 #include <simgear/misc/sg_path.hxx>
43 #include <simgear/math/sg_geodesy.hxx>
45 #include <Main/fg_props.hxx>
46 #include <Main/globals.hxx>
47 #include <Cockpit/panel.hxx>
48 #include <Cockpit/hud.hxx>
49 #include <AIModel/AIBase.hxx>
50 #include <AIModel/AIManager.hxx>
51 #include <AIModel/AIBallistic.hxx>
53 #include "instrument_mgr.hxx"
54 #include "od_gauge.hxx"
55 #include "wxradar.hxx"
58 typedef list <SGSharedPtr<FGAIBase> > radar_list_type;
59 typedef radar_list_type::iterator radar_list_iterator;
60 typedef radar_list_type::const_iterator radar_list_const_iterator;
63 // texture name to use in 2D and 3D instruments
64 static const char *ODGAUGE_NAME = "Aircraft/Instruments/Textures/od_wxradar.rgb";
65 static const float UNIT = 1.0f / 8.0f; // 8 symbols in a row/column in the texture
68 wxRadarBg::wxRadarBg ( SGPropertyNode *node) :
69 _name(node->getStringValue("name", "radar")),
70 _num(node->getIntValue("number", 0)),
71 _interval(node->getDoubleValue("update-interval-sec", 1.0)),
73 _last_switchKnob( "off" ),
74 _sim_init_done ( false ),
79 const char *tacan_source = node->getStringValue("tacan-source",
80 "/instrumentation/tacan");
81 _Tacan = fgGetNode(tacan_source, true);
85 wxRadarBg::~wxRadarBg ()
94 branch = "/instrumentation/" + _name;
96 _Instrument = fgGetNode(branch.c_str(), _num, true );
97 _serviceable_node = _Instrument->getNode("serviceable", true);
98 _resultTexture = FGTextureManager::createTexture( ODGAUGE_NAME );
100 SGPath tpath(globals->get_fg_root());
101 string path = _Instrument->getStringValue("echo-texture-path",
102 "Aircraft/Instruments/Textures/wxecho.rgb");
105 // no mipmap or else alpha will mix with pixels on the border of shapes, ruining the effect
106 _wxEcho = SGLoadTexture2D(tpath.c_str(), false, false);
108 _Instrument->setFloatValue("trk", 0.0);
109 _Instrument->setFloatValue("tilt", 0.0);
110 _Instrument->setStringValue("status","");
111 // those properties are used by a radar instrument of a MFD
112 // input switch = OFF | TST | STBY | ON
113 // input mode = WX | WXA | MAP
114 // output status = STBY | TEST | WX | WXA | MAP | blank
115 // input lightning = true | false
116 // input TRK = +/- n degrees
117 // input TILT = +/- n degree
118 // input autotilt = true | false
119 // input range = n nm (20/40/80)
120 // input display-mode = arc | rose | map | plan
122 FGInstrumentMgr *imgr = (FGInstrumentMgr *) globals->get_subsystem("instrumentation");
123 _odg = (FGODGauge *) imgr->get_subsystem("od_gauge");
126 _ai = (FGAIManager*)globals->get_subsystem("ai_model");
127 _ai_enabled_node = fgGetNode("/sim/ai/enabled", true);
129 _user_lat_node = fgGetNode("/position/latitude-deg", true);
130 _user_lon_node = fgGetNode("/position/longitude-deg", true);
131 _user_alt_node = fgGetNode("/position/altitude-ft", true);
133 _user_speed_east_fps_node = fgGetNode("/velocities/speed-east-fps", true);
134 _user_speed_north_fps_node = fgGetNode("/velocities/speed-north-fps", true);
136 _tacan_serviceable_node = _Tacan->getNode("serviceable", true);
137 _tacan_distance_node = _Tacan->getNode("indicated-distance-nm", true);
138 _tacan_name_node = _Tacan->getNode("name", true);
139 _tacan_bearing_node = _Tacan->getNode("indicated-bearing-true-deg", true);
140 _tacan_in_range_node = _Tacan->getNode("in-range", true);
142 _radar_mode_control_node = _Instrument->getNode("mode-control", true);
143 _radar_coverage_node = _Instrument->getNode("limit-deg", true);
144 _radar_ref_rng_node = _Instrument->getNode("reference-range-nm", true);
145 _radar_hdg_marker_node = _Instrument->getNode("heading-marker", true);
147 SGPropertyNode *n = _Instrument->getNode("display-controls", true);
148 _radar_weather_node = n->getNode("WX", true);
149 _radar_position_node = n->getNode("pos", true);
150 _radar_data_node = n->getNode("data", true);
151 _radar_centre_node = n->getNode("centre", true);
153 _radar_centre_node->setBoolValue(false);
154 if (_radar_coverage_node->getType() == SGPropertyNode::NONE)
155 _radar_coverage_node->setFloatValue(120);
156 if (_radar_ref_rng_node->getType() == SGPropertyNode::NONE)
157 _radar_ref_rng_node->setDoubleValue(35);
158 if (_radar_hdg_marker_node->getType() == SGPropertyNode::NONE)
159 _radar_hdg_marker_node->setBoolValue(true);
164 // OSG geometry setup. The polygons for the radar returns will be
165 // stored in a single Geometry. The geometry will have several
166 // primitive sets so we can have different kinds of polys and
167 // choose a different overall color for each set.
168 _radarGeode = new osg::Geode;
169 osg::StateSet* stateSet = _radarGeode->getOrCreateStateSet();
170 stateSet->setTextureAttributeAndModes(0, _wxEcho.get());
171 _geom = new osg::Geometry;
172 _geom->setUseDisplayList(false);
173 // Initially allocate space for 128 quads
174 _vertices = new osg::Vec2Array;
175 _vertices->setDataVariance(osg::Object::DYNAMIC);
176 _vertices->reserve(128 * 4);
177 _geom->setVertexArray(_vertices);
178 _texCoords = new osg::Vec2Array;
179 _texCoords->setDataVariance(osg::Object::DYNAMIC);
180 _texCoords->reserve(128 * 4);
181 _geom->setTexCoordArray(0, _texCoords);
182 osg::Vec3Array* colors = new osg::Vec3Array;
183 colors->push_back(osg::Vec3(1.0f, 1.0f, 1.0f)); // color of echos
184 colors->push_back(osg::Vec3(1.0f, 0.0f, 0.0f)); // arc mask
185 colors->push_back(osg::Vec3(0.0f, 0.0f, 0.0f)); // rest of mask
186 _geom->setColorBinding(osg::Geometry::BIND_PER_PRIMITIVE_SET);
187 _geom->setColorArray(colors);
188 osg::PrimitiveSet* pset = new osg::DrawArrays(osg::PrimitiveSet::QUADS);
189 pset->setDataVariance(osg::Object::DYNAMIC);
190 _geom->addPrimitiveSet(pset);
191 pset = new osg::DrawArrays(osg::PrimitiveSet::QUADS);
192 pset->setDataVariance(osg::Object::DYNAMIC);
193 _geom->addPrimitiveSet(pset);
194 pset = new osg::DrawArrays(osg::PrimitiveSet::TRIANGLES);
195 pset->setDataVariance(osg::Object::DYNAMIC);
196 _geom->addPrimitiveSet(pset);
197 _geom->setInitialBound(osg::BoundingBox(osg::Vec3f(-256.0f, -256.0f, 0.0f),
198 osg::Vec3f(256.0f, 256.0f, 0.0f)));
199 _radarGeode->addDrawable(_geom);
201 // Texture in the 2D panel system
202 FGTextureManager::addTexture(ODGAUGE_NAME, _odg->getTexture());
204 osg::Camera* camera = _odg->getCamera();
205 camera->addChild(_radarGeode.get());
209 // Local coordinates for each echo
210 const osg::Vec3f echoCoords[4] = {
211 osg::Vec3f(-.7f, -.7f, 0.0f), osg::Vec3f(.7f, -.7f, 0.0f),
212 osg::Vec3f(.7f, .7f, 0.0f), osg::Vec3f(-.7f, .7f, 0.0f)
216 const osg::Vec2f echoTexCoords[4] = {
217 osg::Vec2f(0.0f, 0.0f), osg::Vec2f(UNIT, 0.0f),
218 osg::Vec2f(UNIT, UNIT), osg::Vec2f(0.0f, UNIT)
224 addQuad(osg::Vec2Array* vertices, osg::Vec2Array* texCoords,
225 const osg::Matrixf& transform, const osg::Vec2f& texBase)
227 for (int i = 0; i < 4; i++) {
228 const osg::Vec3f coords = transform.preMult(echoCoords[i]);
229 texCoords->push_back(texBase + echoTexCoords[i]);
230 vertices->push_back(osg::Vec2f(coords.x(), coords.y()));
235 // Rotate by a heading value
237 osg::Matrixf wxRotate(float angle)
239 return osg::Matrixf::rotate(angle, 0.0f, 0.0f, -1.0f);
244 wxRadarBg::update (double delta_time_sec)
246 if ( ! _sim_init_done ) {
247 if ( ! fgGetBool("sim/sceneryloaded", false) )
250 _sim_init_done = true;
252 if ( !_odg || ! _serviceable_node->getBoolValue() ) {
253 _Instrument->setStringValue("status","");
256 _time += delta_time_sec;
257 if (_time < _interval)
262 string mode = _Instrument->getStringValue("display-mode", "arc");
264 if (_display_mode != MAP) {
268 } else if (mode == "plan") {
269 _display_mode = PLAN;
274 string switchKnob = _Instrument->getStringValue("switch", "on");
275 if ( _last_switchKnob != switchKnob ) {
276 // since 3D models don't share textures with the rest of the world
277 // we must locate them and replace their handle by hand
278 // only do that when the instrument is turned on
279 //if ( _last_switchKnob == "off" )
280 //_odg->set_texture( ODGAUGE_NAME, _resultTexture->getHandle());
281 _last_switchKnob = switchKnob;
284 if ( switchKnob == "off" ) {
285 _Instrument->setStringValue("status","");
286 } else if ( switchKnob == "stby" ) {
287 _Instrument->setStringValue("status","STBY");
288 } else if ( switchKnob == "tst" ) {
289 _Instrument->setStringValue("status","TST");
290 // find something interesting to do...
292 float r = _Instrument->getFloatValue("range", 40.0);
293 if (r != _range_nm) {
298 _radar_ref_rng = _radar_ref_rng_node->getDoubleValue();
299 _view_heading = get_heading() * SG_DEGREES_TO_RADIANS;
300 _centerTrans.makeTranslate(0.0f, 0.0f, 0.0f);
302 _scale = 200.0 / _range_nm;
305 if ( _display_mode == ARC ) {
306 _scale = 2*200.0f / _range_nm;
307 _angle_offset = -_view_heading;
308 _centerTrans.makeTranslate(0.0f, -200.0f, 0.0f);
310 } else if ( _display_mode == MAP ) {
313 bool centre = _radar_centre_node->getBoolValue();
316 _radar_centre_node->setBoolValue(false);
319 //SG_LOG(SG_GENERAL, SG_DEBUG, "Radar: displacement "
320 // << _x_offset <<", "<<_y_offset
321 // << " user_speed_east_fps * SG_FPS_TO_KT "
322 // << user_speed_east_fps * SG_FPS_TO_KT
323 // << " user_speed_north_fps * SG_FPS_TO_KT "
324 // << user_speed_north_fps * SG_FPS_TO_KT
325 // << " dt " << delta_time_sec);
327 _centerTrans.makeTranslate(_x_offset, _y_offset, 0.0f);
329 } else if ( _display_mode == PLAN ) {
330 // no sense I presume
342 osg::DrawArrays* quadPSet
343 = static_cast<osg::DrawArrays*>(_geom->getPrimitiveSet(0));
344 quadPSet->set(osg::PrimitiveSet::QUADS, 0, _vertices->size());
347 // erase what is out of sight of antenna
358 osg::DrawArrays* maskPSet
359 = static_cast<osg::DrawArrays*>(_geom->getPrimitiveSet(1));
360 osg::DrawArrays* trimaskPSet
361 = static_cast<osg::DrawArrays*>(_geom->getPrimitiveSet(2));
363 if ( _display_mode == ARC ) {
364 float xOffset = 256.0f;
365 float yOffset = 200.0f;
367 int firstQuadVert = _vertices->size();
368 _texCoords->push_back(osg::Vec2f(0.5f, 0.25f));
369 _vertices->push_back(osg::Vec2f(-xOffset, 0.0 + yOffset));
370 _texCoords->push_back(osg::Vec2f(1.0f, 0.25f));
371 _vertices->push_back(osg::Vec2f(xOffset, 0.0 + yOffset));
372 _texCoords->push_back(osg::Vec2f(1.0f, 0.5f));
373 _vertices->push_back(osg::Vec2f(xOffset, 256.0 + yOffset));
374 _texCoords->push_back(osg::Vec2f(0.5f, 0.5f));
375 _vertices->push_back(osg::Vec2f(-xOffset, 256.0 + yOffset));
376 maskPSet->set(osg::PrimitiveSet::QUADS, firstQuadVert, 4);
378 // The triangles aren't supposed to be textured, but there's
379 // no need to set up a different Geometry, switch modes,
380 // etc. I happen to know that there's a white pixel in the
381 // texture at 1.0, 0.0 :)
382 float centerY = tan(30 * SG_DEGREES_TO_RADIANS);
383 _vertices->push_back(osg::Vec2f(0.0, 0.0));
384 _vertices->push_back(osg::Vec2f(-256.0, 0.0));
385 _vertices->push_back(osg::Vec2f(-256.0, 256.0 * centerY));
387 _vertices->push_back(osg::Vec2f(0.0, 0.0));
388 _vertices->push_back(osg::Vec2f(256.0, 0.0));
389 _vertices->push_back(osg::Vec2f(256.0, 256.0 * centerY));
391 _vertices->push_back(osg::Vec2f(-256, 0.0));
392 _vertices->push_back(osg::Vec2f(256.0, 0.0));
393 _vertices->push_back(osg::Vec2f(-256.0, -256.0));
395 _vertices->push_back(osg::Vec2f(256, 0.0));
396 _vertices->push_back(osg::Vec2f(256.0, -256.0));
397 _vertices->push_back(osg::Vec2f(-256.0, -256.0));
399 const osg::Vec2f whiteSpot(1.0f, 0.0f);
400 for (int i = 0; i < 3 * 4; i++)
401 _texCoords->push_back(whiteSpot);
403 trimaskPSet->set(osg::PrimitiveSet::TRIANGLES, firstQuadVert + 4,
407 maskPSet->set(osg::PrimitiveSet::QUADS, 0, 0);
408 trimaskPSet->set(osg::PrimitiveSet::TRIANGLES, 0, 0);
412 trimaskPSet->dirty();
420 update_heading_marker();
422 quadPSet->set(osg::PrimitiveSet::QUADS, 0, _vertices->size());
429 wxRadarBg::update_weather()
431 string modeButton = _Instrument->getStringValue("mode", "wx");
432 _radarEchoBuffer = *sgEnviro.get_radar_echo();
434 // pretend we have a scan angle bigger then the FOV
435 // TODO:check real fov, enlarge if < nn, and do clipping if > mm
436 const float fovFactor = 1.45f;
437 _Instrument->setStringValue("status", modeButton.c_str());
439 list_of_SGWxRadarEcho *radarEcho = &_radarEchoBuffer;
440 list_of_SGWxRadarEcho::iterator iradarEcho, end = radarEcho->end();
441 const float LWClevel[] = { 0.1f, 0.5f, 2.1f };
443 // draw the cloud radar echo
444 bool drawClouds = _radar_weather_node->getBoolValue();
447 // we do that in 3 passes, one for each color level
448 // this is to 'merge' same colors together
449 for (int level = 0; level <= 2; level++) {
450 float col = level * UNIT;
452 for (iradarEcho = radarEcho->begin(); iradarEcho != end; ++iradarEcho) {
453 int cloudId = iradarEcho->cloudId;
454 bool upgrade = (cloudId >> 5) & 1;
455 float lwc = iradarEcho->LWC + (upgrade ? 1.0f : 0.0f);
458 if (iradarEcho->LWC >= 0.5 && iradarEcho->LWC <= 0.6)
461 if (iradarEcho->lightning || lwc < LWClevel[level])
464 float radius = sgSqrt(iradarEcho->dist) * SG_METER_TO_NM * _scale;
465 float size = iradarEcho->radius * 2.0 * SG_METER_TO_NM * _scale;
467 if (radius - size > 180)
470 float angle = (iradarEcho->heading - _angle_offset) //* fovFactor
473 // Rotate echo into position, and rotate echo to have
474 // a constant orientation towards the
475 // airplane. Compass headings increase in clockwise
476 // direction, while graphics rotations follow
477 // right-hand (counter-clockwise) rule.
478 const osg::Vec2f texBase(col, (UNIT * (float) (4 + (cloudId & 3))));
480 osg::Matrixf m(osg::Matrixf::scale(size, size, 1.0f)
481 * osg::Matrixf::translate(0.0f, radius, 0.0f)
482 * wxRotate(angle) * _centerTrans);
483 addQuad(_vertices, _texCoords, m, texBase);
485 //SG_LOG(SG_GENERAL, SG_DEBUG, "Radar: drawing clouds"
486 // << " ID=" << cloudId
489 // << " radius=" << radius
490 // << " view_heading=" << _view_heading * SG_RADIANS_TO_DEGREES
491 // << " heading=" << iradarEcho->heading * SG_RADIANS_TO_DEGREES
492 // << " angle=" << angle * SG_RADIANS_TO_DEGREES);
497 // draw lightning echos
498 bool drawLightning = _Instrument->getBoolValue("lightning", true);
499 if ( drawLightning ) {
500 const osg::Vec2f texBase(3 * UNIT, 4 * UNIT);
502 for (iradarEcho = radarEcho->begin(); iradarEcho != end; ++iradarEcho) {
503 if (!iradarEcho->lightning)
506 float size = UNIT * 0.5f;
507 float radius = iradarEcho->dist * _scale;
508 float angle = iradarEcho->heading * SG_DEGREES_TO_RADIANS
511 osg::Matrixf m(osg::Matrixf::scale(size, size, 1.0f)
513 * osg::Matrixf::translate(0.0f, radius, 0.0f)
514 * wxRotate(angle) * _centerTrans);
515 addQuad(_vertices, _texCoords, m, texBase);
522 wxRadarBg::update_aircraft()
524 if (!_ai_enabled_node->getBoolValue())
527 bool draw_echoes = _radar_position_node->getBoolValue();
528 bool draw_symbols = _radar_data_node->getBoolValue();
529 if (!draw_echoes && !draw_symbols)
532 radar_list_type radar_list = _ai->get_ai_list();
533 SG_LOG(SG_GENERAL, SG_DEBUG, "Radar: AI submodel list size" << radar_list.size());
534 if (radar_list.empty())
537 SG_LOG(SG_GENERAL, SG_DEBUG, "Radar: Loading AI submodels ");
538 const double echo_radii[] = {0, 1, 1.5, 1.5, 0.001, 0.1, 1.5, 2, 1.5, 1.5};
540 double user_lat = _user_lat_node->getDoubleValue();
541 double user_lon = _user_lon_node->getDoubleValue();
542 double user_alt = _user_alt_node->getDoubleValue();
544 radar_list_iterator it = radar_list.begin();
545 radar_list_iterator end = radar_list.end();
547 for (; it != end; ++it) {
549 int type = ac->getType();
550 double lat = ac->_getLatitude();
551 double lon = ac->_getLongitude();
552 double alt = ac->_getAltitude();
553 double heading = ac->_getHeading();
555 double range, bearing;
556 calcRangeBearing(user_lat, user_lon, lat, lon, range, bearing);
558 //SG_LOG(SG_GENERAL, SG_DEBUG,
559 // "Radar: ID=" << ac->getID() << "(" << radar_list.size() << ")"
560 // << " type=" << type
561 // << " view_heading=" << _view_heading * SG_RADIANS_TO_DEGREES
563 // << " heading=" << heading
564 // << " range=" << range
565 // << " bearing=" << bearing);
567 bool isVisible = withinRadarHorizon(user_alt, alt, range);
568 SG_LOG(SG_GENERAL, SG_DEBUG, "Radar: visible " << isVisible);
572 if (!inRadarRange(type, range))
575 bearing *= SG_DEGREES_TO_RADIANS;
576 heading *= SG_DEGREES_TO_RADIANS;
578 float radius = range * _scale;
579 float angle = calcRelBearing(bearing, _view_heading);
581 float limit = _radar_coverage_node->getFloatValue();
586 limit *= SG_DEGREES_TO_RADIANS;
587 if (angle > limit || angle < -limit)
590 bearing += _angle_offset;
591 heading += _angle_offset;
595 float echo_radius = echo_radii[type] * 120;
596 float size = echo_radius * UNIT;
598 const osg::Vec2f texBase(3 * UNIT, 3 * UNIT);
599 osg::Matrixf m(osg::Matrixf::scale(size, size, 1.0f)
600 * osg::Matrixf::translate(0.0f, radius, 0.0f)
601 * wxRotate(bearing) * _centerTrans);
602 addQuad(_vertices, _texCoords, m, texBase);
604 //SG_LOG(SG_GENERAL, SG_DEBUG, "Radar: drawing AI"
605 // << " x=" << x << " y=" << y
606 // << " radius=" << radius
607 // << " angle=" << angle * SG_RADIANS_TO_DEGREES);
612 const osg::Vec2f texBase(0, 3 * UNIT);
613 float size = 600 * UNIT;
614 osg::Matrixf m(osg::Matrixf::scale(size, size, 1.0f)
615 * wxRotate(heading - bearing)
616 * osg::Matrixf::translate(0.0f, radius, 0.0f)
617 * wxRotate(bearing) * _centerTrans);
618 addQuad(_vertices, _texCoords, m, texBase);
620 //SG_LOG(SG_GENERAL, SG_DEBUG, "Radar: drawing data"
621 // << " x=" << x <<" y="<< y
622 // << " bearing=" << angle * SG_RADIANS_TO_DEGREES
623 // << " radius=" << radius);
630 wxRadarBg::update_tacan()
633 int mode = _radar_mode_control_node->getIntValue();
634 bool inRange = _tacan_in_range_node->getBoolValue();
636 if (mode != 1 || !inRange)
639 float size = 600 * UNIT;
640 float radius = _tacan_distance_node->getFloatValue() * _scale;
641 float angle = _tacan_bearing_node->getFloatValue() * SG_DEGREES_TO_RADIANS
644 const osg::Vec2f texBase(1 * UNIT, 3 * UNIT);
645 osg::Matrixf m(osg::Matrixf::scale(size, size, 1.0f)
647 * osg::Matrixf::translate(0.0f, radius, 0.0f)
648 * wxRotate(angle) * _centerTrans);
649 addQuad(_vertices, _texCoords, m, texBase);
651 //SG_LOG(SG_GENERAL, SG_DEBUG, "Radar: drawing TACAN"
652 // << " dist=" << radius
653 // << " view_heading=" << _view_heading * SG_RADIANS_TO_DEGREES
654 // << " bearing=" << angle * SG_RADIANS_TO_DEGREES
655 // << " x=" << x << " y="<< y
656 // << " size=" << size);
661 wxRadarBg::update_heading_marker()
663 if (!_radar_hdg_marker_node->getBoolValue())
666 const osg::Vec2f texBase(2 * UNIT, 3 * UNIT);
667 float size = 600 * UNIT;
668 osg::Matrixf m(osg::Matrixf::scale(size, size, 1.0f)
669 * wxRotate(_view_heading + _angle_offset));
672 addQuad(_vertices, _texCoords, m, texBase);
674 //SG_LOG(SG_GENERAL, SG_DEBUG, "Radar: drawing heading marker"
675 // << " x,y " << x <<","<< y
676 // << " dist" << dist
677 // << " view_heading" << _view_heading * SG_RADIANS_TO_DEGREES
678 // << " heading " << iradarEcho->heading * SG_RADIANS_TO_DEGREES
679 // << " angle " << angle * SG_RADIANS_TO_DEGREES);
684 wxRadarBg::center_map()
686 _lat = _user_lat_node->getDoubleValue();
687 _lon = _user_lon_node->getDoubleValue();
688 _x_offset = _y_offset = 0;
693 wxRadarBg::apply_map_offset()
695 double lat = _user_lat_node->getDoubleValue();
696 double lon = _user_lon_node->getDoubleValue();
697 double bearing, distance, az2;
698 geo_inverse_wgs_84(_lat, _lon, lat, lon, &bearing, &az2, &distance);
699 distance *= SG_METER_TO_NM * _scale;
700 bearing *= SG_DEGREES_TO_RADIANS;
701 _x_offset += sin(bearing) * distance;
702 _y_offset += cos(bearing) * distance;
709 wxRadarBg::withinRadarHorizon(double user_alt, double alt, double range_nm)
711 // Radar Horizon = 1.23(ht^1/2 + hr^1/2),
712 //don't allow negative altitudes (an approximation - yes altitudes can be negative)
720 double radarhorizon = 1.23 * (sqrt(alt) + sqrt(user_alt));
721 SG_LOG(SG_GENERAL, SG_DEBUG, "Radar: horizon " << radarhorizon);
722 return radarhorizon >= range_nm;
727 wxRadarBg::inRadarRange(int type, double range_nm)
729 //The Radar Equation:
731 // MaxRange^4 = (TxPower * AntGain^2 * lambda^2 * sigma)/((constant) * MDS)
733 // Where (constant) = (4*pi)3 and MDS is the Minimum Detectable Signal power.
735 // For a given radar we can assume that the only variable is sigma,
736 // the target radar cross section.
738 // Here, we will use a normalised rcs (sigma) for a standard taget and assume that this
739 // will provide a maximum range of 35nm;
741 // TODO - make the maximum range adjustable at runtime
743 const double sigma[] = {0, 1, 100, 100, 0.001, 0.1, 100, 100, 1, 1};
744 double constant = _radar_ref_rng;
749 double maxrange = constant * pow(sigma[type], 0.25);
750 SG_LOG(SG_GENERAL, SG_DEBUG, "Radar: max range " << maxrange);
751 return maxrange >= range_nm;
756 wxRadarBg::calcRangeBearing(double lat, double lon, double lat2, double lon2,
757 double &range, double &bearing ) const
759 // calculate the bearing and range of the second pos from the first
760 double az2, distance;
761 geo_inverse_wgs_84(lat, lon, lat2, lon2, &bearing, &az2, &distance);
762 range = distance *= SG_METER_TO_NM;
767 wxRadarBg::calcRelBearing(float bearing, float heading)
769 float angle = bearing - heading;
772 angle -= 2.0 * SG_PI;
775 angle += 2.0 * SG_PI;