1 // HUD_runway.cxx -- An instrument that renders a virtual runway on the HUD
2 //
3 // Written by Aaron Wilson & Phillip Merritt, Nov 2004.
4 //
5 // Copyright (C) 2004 Aaron Wilson, Aaron.I.Wilson@nasa.gov
6 // Copyright (C) 2004 Phillip Merritt, Phillip.M.Merritt@nasa.gov
7 //
8 // This program is free software; you can redistribute it and/or
9 // modify it under the terms of the GNU General Public License as
10 // published by the Free Software Foundation; either version 2 of the
11 // License, or (at your option) any later version.
12 //
13 // This program is distributed in the hope that it will be useful, but
14 // WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 // General Public License for more details.
17 //
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
21
22 #ifdef HAVE_CONFIG_H
23 # include <config.h>
24 #endif
25
26 #include <simgear/compiler.h>
27 #include <simgear/math/sg_geodesy.hxx>
28 #include <simgear/scene/util/project.hxx>
29
30 #include <Main/globals.hxx>
31 #include <Main/fg_props.hxx>
32 #include <Scenery/scenery.hxx>
33 #include <Aircraft/controls.hxx>
34 #include <FDM/flight.hxx>
35 #include <Environment/environment.hxx>
36 #include <Environment/environment_mgr.hxx>
37 #include <Viewer/view.hxx>
38 #include <Viewer/viewmgr.hxx>
39 #include <Airports/airport.hxx>
40
41 #include "HUD.hxx"
42 #include "HUD_private.hxx"
43
Runway(HUD * hud,const SGPropertyNode * node,float x,float y)44 HUD::Runway::Runway(HUD *hud, const SGPropertyNode *node, float x, float y) :
45 Item(hud, node, x, y),
46 _agl(fgGetNode("/position/altitude-agl-ft", true)),
47 _arrow_scale(node->getDoubleValue("arrow-scale", 1.0)),
48 _arrow_radius(node->getDoubleValue("arrow-radius")),
49 _line_scale(node->getDoubleValue("line-scale", 1.0)),
50 _scale_dist(node->getDoubleValue("scale-dist-nm")),
51 _default_pitch(fgGetDouble("/sim/view[0]/config/pitch-pitch-deg", 0.0)),
52 _default_heading(fgGetDouble("/sim/view[0]/config/pitch-heading-deg", 0.0)),
53 _stipple_out(node->getIntValue("outer_stipple", 0xFFFF)),
54 _stipple_center(node->getIntValue("center-stipple", 0xFFFF)),
55 _draw_arrow(_arrow_scale > 0 ? true : false),
56 _draw_arrow_always(_arrow_scale > 0 ? node->getBoolValue("arrow-always") : false)
57 {
58 _view[0] = 0;
59 _view[1] = 0;
60 _view[2] = 640;
61 _view[3] = 480;
62
63 _center_x = _view[2] / 2;
64 _center_y = _view[3] / 2;
65
66 _left = _center_x - (_w / 2) + _x;
67 _right = _center_x + (_w / 2) + _x;
68 _bottom = _center_y - (_h / 2) + _y;
69 _top = _center_y + (_h / 2) + _y;
70 }
71
draw()72 void HUD::Runway::draw()
73 {
74 _runway = get_active_runway();
75 if (!_runway)
76 return;
77
78 glPushAttrib(GL_LINE_STIPPLE | GL_LINE_STIPPLE_PATTERN | GL_LINE_WIDTH);
79 float projMat[4][4]={{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0}};
80 float modelView[4][4];
81 bool anyLines;
82 //Get the current view
83 // FGViewer* curr_view = globals->get_viewmgr()->get_current_view();
84 // int curr_view_id = globals->get_viewmgr()->get_current();
85 // double gpo = curr_view->getGoalPitchOffset_deg();
86 // double gho = curr_view->getGoalHeadingOffset_deg();
87 // double po = curr_view->getPitchOffset_deg();
88 // double ho = curr_view->getHeadingOffset_deg();
89
90 flightgear::View* cockpitView = globals->get_viewmgr()->get_view(0);
91
92 double yaw = -(cockpitView->getHeadingOffset_deg() - _default_heading) * SG_DEGREES_TO_RADIANS;
93 double pitch = (cockpitView->getPitchOffset_deg() - _default_pitch) * SG_DEGREES_TO_RADIANS;
94 //double roll = fgGetDouble("/sim/view[0]/config/roll-offset-deg",0.0) //TODO: adjust for default roll offset
95 double sPitch = sin(pitch), cPitch = cos(pitch),
96 sYaw = sin(yaw), cYaw = cos(yaw);
97
98 //Set the camera to the cockpit view to get the view of the runway from the cockpit
99 // OSGFIXME
100 // ssgSetCamera((sgVec4 *)_cockpit_view->get_VIEW());
101 get_rwy_points(_points3d);
102 //Get the current project matrix
103 // OSGFIXME
104 // ssgGetProjectionMatrix(projMat);
105 // const sgVec4 *viewMat = globals->get_current_view()->get_VIEW();
106 //Get the current model view matrix (cockpit view)
107 // OSGFIXME
108 // ssgGetModelviewMatrix(modelView);
109 //Create a rotation matrix to correct for any offsets (other than default offsets) to the model view matrix
110 sgMat4 xy; //rotation about the Rxy, negate the sin's on Ry
111 xy[0][0] = cYaw, xy[1][0] = 0.0f, xy[2][0] = -sYaw, xy[3][0] = 0.0f;
112 xy[0][1] = sPitch*-sYaw, xy[1][1] = cPitch, xy[2][1] = -sPitch*cYaw, xy[3][1] = 0.0f;
113 xy[0][2] = cPitch*sYaw, xy[1][2] = sPitch, xy[2][2] = cPitch*cYaw, xy[3][2] = 0.0f;
114 xy[0][3] = 0.0f, xy[1][3] = 0.0f, xy[2][3] = 0.0f, xy[3][3] = 1.0f;
115 //Re-center the model view
116 sgPostMultMat4(modelView,xy);
117 //copy float matrices to double
118 for (int i = 0; i < 4; i++) {
119 for (int j = 0; j < 4; j++) {
120 int idx = (i * 4) + j;
121 _mm[idx] = (double)modelView[i][j];
122 _pm[idx] = (double)projMat[i][j];
123 }
124 }
125
126 //Calculate the 2D points via gluProject
127 // int result = GL_TRUE;
128 for (int i = 0; i < 6; i++) {
129 /*result = */simgear::project(_points3d[i][0], _points3d[i][1], _points3d[i][2],
130 _mm, _pm, _view,
131 &_points2d[i][0], &_points2d[i][1], &_points2d[i][2]);
132 }
133 //set the line width based on our distance from the runway
134 setLineWidth();
135 //Draw the runway lines on the HUD
136 glEnable(GL_LINE_STIPPLE);
137 glLineStipple(1, _stipple_out);
138 anyLines =
139 drawLine(_points3d[0], _points3d[1], _points2d[0], _points2d[1]) | //draw top
140 drawLine(_points3d[2], _points3d[1], _points2d[2], _points2d[1]) | //draw right
141 drawLine(_points3d[2], _points3d[3], _points2d[2], _points2d[3]) | //draw bottom
142 drawLine(_points3d[3], _points3d[0], _points2d[3], _points2d[0]); //draw left
143
144 glLineStipple(1, _stipple_center);
145 anyLines |= drawLine(_points3d[5], _points3d[4], _points2d[5], _points2d[4]); //draw center
146
147 //Check to see if arrow needs drawn
148 if ((!anyLines && _draw_arrow) || _draw_arrow_always) {
149 drawArrow(); //draw indication arrow
150 }
151
152 //Set the camera back to the current view
153 // OSGFIXME
154 // ssgSetCamera((sgVec4 *)curr_view);
155 glPopAttrib();
156 }
157
158
get_active_runway()159 FGRunway* HUD::Runway::get_active_runway()
160 {
161 const FGAirport* apt = fgFindAirportID(fgGetString("/sim/presets/airport-id"));
162 if (!apt) return NULL;
163
164 return apt->getActiveRunwayForUsage();
165 }
166
167
168
get_rwy_points(sgdVec3 * _points3d)169 void HUD::Runway::get_rwy_points(sgdVec3 *_points3d)
170 {
171 double alt = _runway->geod().getElevationM();
172 double length = _runway->lengthM() * 0.5;
173 double width = _runway->widthM() * 0.5;
174 double frontLat = 0.0, frontLon = 0.0, backLat = 0.0, backLon = 0.0, az = 0.0, tempLat = 0.0, tempLon = 0.0;
175
176 geo_direct_wgs_84(alt, _runway->latitude(), _runway->longitude(), _runway->headingDeg(), length, &backLat, &backLon, &az);
177 sgGeodToCart(backLat * SG_DEGREES_TO_RADIANS, backLon * SG_DEGREES_TO_RADIANS, alt, _points3d[4]);
178
179 geo_direct_wgs_84(alt, _runway->latitude(), _runway->longitude(), _runway->headingDeg() + 180, length, &frontLat, &frontLon, &az);
180 sgGeodToCart(frontLat * SG_DEGREES_TO_RADIANS, frontLon * SG_DEGREES_TO_RADIANS, alt, _points3d[5]);
181
182 geo_direct_wgs_84(alt, backLat, backLon, _runway->headingDeg() + 90, width, &tempLat, &tempLon, &az);
183 sgGeodToCart(tempLat * SG_DEGREES_TO_RADIANS, tempLon * SG_DEGREES_TO_RADIANS, alt, _points3d[0]);
184
185 geo_direct_wgs_84(alt, backLat, backLon, _runway->headingDeg() - 90, width, &tempLat, &tempLon, &az);
186 sgGeodToCart(tempLat * SG_DEGREES_TO_RADIANS, tempLon * SG_DEGREES_TO_RADIANS, alt, _points3d[1]);
187
188 geo_direct_wgs_84(alt, frontLat, frontLon, _runway->headingDeg() - 90, width, &tempLat, &tempLon, &az);
189 sgGeodToCart(tempLat * SG_DEGREES_TO_RADIANS, tempLon * SG_DEGREES_TO_RADIANS, alt, _points3d[2]);
190
191 geo_direct_wgs_84(alt, frontLat, frontLon, _runway->headingDeg() + 90, width, &tempLat, &tempLon, &az);
192 sgGeodToCart(tempLat * SG_DEGREES_TO_RADIANS, tempLon * SG_DEGREES_TO_RADIANS, alt, _points3d[3]);
193 }
194
195
drawLine(const sgdVec3 & a1,const sgdVec3 & a2,const sgdVec3 & point1,const sgdVec3 & point2)196 bool HUD::Runway::drawLine(const sgdVec3& a1, const sgdVec3& a2, const sgdVec3& point1, const sgdVec3& point2)
197 {
198 sgdVec3 p1, p2;
199 sgdCopyVec3(p1, point1);
200 sgdCopyVec3(p2, point2);
201 bool p1Inside = (p1[0] >= _left && p1[0] <= _right && p1[1] >= _bottom && p1[1] <= _top);
202 bool p1Insight = (p1[2] >= 0.0 && p1[2] < 1.0);
203 bool p1Valid = p1Insight && p1Inside;
204 bool p2Inside = (p2[0] >= _left && p2[0] <= _right && p2[1] >= _bottom && p2[1] <= _top);
205 bool p2Insight = (p2[2] >= 0.0 && p2[2] < 1.0);
206 bool p2Valid = p2Insight && p2Inside;
207
208 if (p1Valid && p2Valid) { //Both project points are valid, draw the line
209 glBegin(GL_LINES);
210 glVertex2d(p1[0],p1[1]);
211 glVertex2d(p2[0],p2[1]);
212 glEnd();
213
214 } else if (p1Valid) { //p1 is valid and p2 is not, calculate a new valid point
215 sgdVec3 vec = {a2[0] - a1[0], a2[1] - a1[1], a2[2] - a1[2]};
216 //create the unit vector
217 sgdScaleVec3(vec, 1.0 / sgdLengthVec3(vec));
218 sgdVec3 newPt;
219 sgdCopyVec3(newPt, a1);
220 sgdAddVec3(newPt, vec);
221 if (simgear::project(newPt[0], newPt[1], newPt[2], _mm, _pm, _view,
222 &p2[0], &p2[1], &p2[2])
223 && (p2[2] > 0 && p2[2] < 1.0)) {
224 boundPoint(p1, p2);
225 glBegin(GL_LINES);
226 glVertex2d(p1[0], p1[1]);
227 glVertex2d(p2[0], p2[1]);
228 glEnd();
229 }
230
231 } else if (p2Valid) { //p2 is valid and p1 is not, calculate a new valid point
232 sgdVec3 vec = {a1[0] - a2[0], a1[1] - a2[1], a1[2] - a2[2]};
233 //create the unit vector
234 sgdScaleVec3(vec, 1.0 / sgdLengthVec3(vec));
235 sgdVec3 newPt;
236 sgdCopyVec3(newPt, a2);
237 sgdAddVec3(newPt, vec);
238 if (simgear::project(newPt[0], newPt[1], newPt[2], _mm, _pm, _view,
239 &p1[0], &p1[1], &p1[2])
240 && (p1[2] > 0 && p1[2] < 1.0)) {
241 boundPoint(p2, p1);
242 glBegin(GL_LINES);
243 glVertex2d(p2[0], p2[1]);
244 glVertex2d(p1[0], p1[1]);
245 glEnd();
246 }
247
248 } else if (p1Insight && p2Insight) { //both points are insight, but not inside
249 bool v = boundOutsidePoints(p1, p2);
250 if (v) {
251 glBegin(GL_LINES);
252 glVertex2d(p1[0], p1[1]);
253 glVertex2d(p2[0], p2[1]);
254 glEnd();
255 }
256 return v;
257 }
258 //else both points are not insight, don't draw anything
259 return (p1Valid && p2Valid);
260 }
261
262
boundPoint(const sgdVec3 & v,sgdVec3 & m)263 void HUD::Runway::boundPoint(const sgdVec3& v, sgdVec3& m)
264 {
265 double y = v[1];
266 if (m[1] < v[1])
267 y = _bottom;
268 else if (m[1] > v[1])
269 y = _top;
270
271 if (m[0] == v[0]) {
272 m[1] = y;
273 return; //prevent divide by zero
274 }
275
276 double slope = (m[1] - v[1]) / (m[0] - v[0]);
277 m[0] = (y - v[1]) / slope + v[0];
278 m[1] = y;
279
280 if (m[0] < _left) {
281 m[0] = _left;
282 m[1] = slope * (_left - v[0]) + v[1];
283
284 } else if (m[0] > _right) {
285 m[0] = _right;
286 m[1] = slope * (_right - v[0]) + v[1];
287 }
288 }
289
290
boundOutsidePoints(sgdVec3 & v,sgdVec3 & m)291 bool HUD::Runway::boundOutsidePoints(sgdVec3& v, sgdVec3& m)
292 {
293 bool pointsInvalid = (v[1] > _top && m[1] > _top) ||
294 (v[1] < _bottom && m[1] < _bottom) ||
295 (v[0] > _right && m[0] > _right) ||
296 (v[0] < _left && m[0] < _left);
297 if (pointsInvalid)
298 return false;
299
300 if (m[0] == v[0]) {//x's are equal, vertical line
301 if (m[1] > v[1]) {
302 m[1] = _top;
303 v[1] = _bottom;
304 } else {
305 v[1] = _top;
306 m[1] = _bottom;
307 }
308 return true;
309 }
310
311 if (m[1] == v[1]) { //y's are equal, horizontal line
312 if (m[0] > v[0]) {
313 m[0] = _right;
314 v[0] = _left;
315 } else {
316 v[0] = _right;
317 m[0] = _left;
318 }
319 return true;
320 }
321
322 double slope = (m[1] - v[1]) / (m[0] - v[0]);
323 double b = v[1] - (slope * v[0]);
324 double y1 = slope * _left + b;
325 double y2 = slope * _right + b;
326 double x1 = (_bottom - b) / slope;
327 double x2 = (_top - b) / slope;
328 int counter = 0;
329
330 if (y1 >= _bottom && y1 <= _top) {
331 v[0] = _left;
332 v[1] = y1;
333 counter++;
334 }
335
336 if (y2 >= _bottom && y2 <= _top) {
337 if (counter > 0) {
338 m[0] = _right;
339 m[1] = y2;
340 } else {
341 v[0] = _right;
342 v[1] = y2;
343 }
344 counter++;
345 }
346
347 if (x1 >= _left && x1 <= _right) {
348 if (counter > 0) {
349 m[0] = x1;
350 m[1] = _bottom;
351 } else {
352 v[0] = x1;
353 v[1] = _bottom;
354 }
355 counter++;
356 }
357
358 if (x2 >= _left && x2 <= _right) {
359 m[0] = x1;
360 m[1] = _bottom;
361 counter++;
362 }
363 return (counter == 2);
364 }
365
366
drawArrow()367 void HUD::Runway::drawArrow()
368 {
369 SGGeod acPos(SGGeod::fromDeg(
370 fgGetDouble("/position/longitude-deg"),
371 fgGetDouble("/position/latitude-deg")));
372 float theta = SGGeodesy::courseDeg(acPos, _runway->geod());
373 theta -= fgGetDouble("/orientation/heading-deg");
374 theta = -theta;
375 glMatrixMode(GL_MODELVIEW);
376 glPushMatrix();
377 glTranslated((_right + _left) / 2.0, (_top + _bottom) / 2.0, 0.0);
378 glRotated(theta, 0.0, 0.0, 1.0);
379 glTranslated(0.0, _arrow_radius, 0.0);
380 glScaled(_arrow_scale, _arrow_scale, 0.0);
381
382 glBegin(GL_TRIANGLES);
383 glVertex2d(-5.0, 12.5);
384 glVertex2d(0.0, 25.0);
385 glVertex2d(5.0, 12.5);
386 glEnd();
387
388 glBegin(GL_QUADS);
389 glVertex2d(-2.5, 0.0);
390 glVertex2d(-2.5, 12.5);
391 glVertex2d(2.5, 12.5);
392 glVertex2d(2.5, 0.0);
393 glEnd();
394 glPopMatrix();
395 }
396
397
setLineWidth()398 void HUD::Runway::setLineWidth()
399 {
400 //Calculate the distance from the runway, A
401 SGGeod acPos(SGGeod::fromDeg(
402 fgGetDouble("/position/longitude-deg"),
403 fgGetDouble("/position/latitude-deg")));
404 double distance = SGGeodesy::distanceNm(acPos, _runway->geod());
405 //Get altitude above runway, B
406 double alt_nm = _agl->getDoubleValue();
407
408 if (_hud->getUnits() == FEET)
409 alt_nm *= SG_FEET_TO_METER;
410
411 alt_nm *= SG_METER_TO_NM;
412
413 //Calculate distance away from runway, C = v(A≤+B≤)
414 distance = sqrt(alt_nm * alt_nm + distance*distance);
415 if (distance < _scale_dist)
416 glLineWidth(1.0 + ((_line_scale - 1) * ((_scale_dist - distance) / _scale_dist)));
417 else
418 glLineWidth(1.0);
419
420 }
421
422
423