src/Cockpit/hud_rwy.cxx

   1 // hud_rwy.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., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 //
  22
  23 #include "hud.hxx"
  24
  25 #include <math.h>
  26 #include <Main/fg_props.hxx>
  27 #include <Main/globals.hxx>
  28 #include <Scenery/scenery.hxx>
  29 #include <Aircraft/aircraft.hxx>
  30 #include <Environment/environment.hxx>
  31 #include <Environment/environment_mgr.hxx>
  32 #include <simgear/math/sg_geodesy.hxx>
  33 #include <simgear/math/polar3d.hxx>
  34 #include <GL/glu.h>
  35 #include <ATC/ATCutils.hxx>
  36
  37 runway_instr::runway_instr(int x,
  38                                                    int y,
  39                                                    int width,
  40                                                    int height,
  41                                                    float scale_data,
  42                                                    bool working):instr_item(x,y,width,height,NULL,scale_data,0,working)
  43 {
  44         runway = get_active_runway();
  45         get_rwy_points(points3d);
  46         stippleOut=0xFFFF;
  47         stippleCen=0xFFFF;
  48         arrowScale = 1.0;
  49         arrowRad = 0.0;
  50         view[0] = 0;
  51         view[1] = 0;
  52         view[2] = 640;
  53         view[3] = 480;
  54         center.x = view[2]>>1;
  55         center.y = view[3]>>1;
  56         location.left = center.x-(width>>1)+x;
  57         location.right = center.x+(width>>1)+x;
  58         location.bottom = center.y-(height>>1)+y;
  59         location.top = center.y+(height>>1)+y;
  60         cockpit_view = globals->get_viewmgr()->get_view(0);
  61         default_heading = fgGetDouble("/sim/view[0]/config/pitch-heading-deg",0.0);
  62         default_pitch = fgGetDouble("/sim/view[0]/config/pitch-pitch-deg",0.0);
  63 }
  64
  65 void runway_instr::draw() {
  66         if (!is_broken()) {
  67                 glPushAttrib(GL_LINE_STIPPLE | GL_LINE_STIPPLE_PATTERN | GL_LINE_WIDTH);
  68                 float modelView[4][4],projMat[4][4];
  69                 bool anyLines;
  70                 //Get the current view
  71                 FGViewer* curr_view = globals->get_viewmgr()->get_current_view();
  72                 int curr_view_id = globals->get_viewmgr()->get_current();
  73                 double gpo = curr_view->getGoalPitchOffset_deg();
  74                 double gho = curr_view->getGoalHeadingOffset_deg();
  75                 double po = curr_view->getPitchOffset_deg();
  76                 double ho = curr_view->getHeadingOffset_deg();
  77
  78                 double yaw = -(cockpit_view->getHeadingOffset_deg()-default_heading)*SG_DEGREES_TO_RADIANS;
  79                 double pitch = (cockpit_view->getPitchOffset_deg()-default_pitch)*SG_DEGREES_TO_RADIANS;
  80                 //double roll = fgGetDouble("/sim/view[0]/config/roll-offset-deg",0.0) //TODO: adjust for default roll offset
  81                 double sPitch = sin(pitch), cPitch = cos(pitch),
  82                            sYaw = sin(yaw), cYaw = cos(yaw);
  83
  84                 //Assuming that the "Cockpit View" is always at position zero!!!
  85                 if (curr_view_id != 0) {
  86                         globals->get_viewmgr()->set_view(0);
  87                         globals->get_viewmgr()->copyToCurrent();
  88                 }
  89                 //Set the camera to the cockpit view to get the view of the runway from the cockpit
  90                 ssgSetCamera((sgVec4 *)cockpit_view->get_VIEW());
  91                 //Get the currently active runway and the 3d points
  92                 runway = get_active_runway();
  93                 get_rwy_points(points3d);
  94                 //Get the current project matrix
  95                 ssgGetProjectionMatrix(projMat);
  96 //              const sgVec4 *viewMat = globals->get_current_view()->get_VIEW();
  97                 //Get the current model view matrix (cockpit view)
  98                 ssgGetModelviewMatrix(modelView);
  99                 //Create a rotation matrix to correct for any offsets (other than default offsets) to the model view matrix
 100                 sgMat4 xy; //rotation about the Rxy, negate the sin's on Ry
 101                 xy[0][0]=cYaw;                  xy[1][0]=0.0f;          xy[2][0]=-sYaw;                 xy[3][0]=0.0f;
 102                 xy[0][1]=sPitch*-sYaw;  xy[1][1]=cPitch;        xy[2][1]=-sPitch*cYaw;  xy[3][1]=0.0f;
 103                 xy[0][2]=cPitch*sYaw;   xy[1][2]=sPitch;        xy[2][2]=cPitch*cYaw;   xy[3][2]=0.0f;
 104                 xy[0][3]=0.0f;                  xy[1][3]=0.0f;          xy[2][3]=0.0f;                  xy[3][3]=1.0f;
 105                 //Re-center the model view
 106                 sgPostMultMat4(modelView,xy);
 107                 //copy float matrices to double
 108                 for (int i=0; i<4; i++) {
 109                         for (int j=0; j<4; j++) {
 110                                 int idx = (i*4)+j;
 111                                 mm[idx] = (double)modelView[i][j];
 112                                 pm[idx] = (double)projMat[i][j];
 113                         }
 114                 }
 115                 //Calculate the 2D points via gluProject
 116                 int result = GL_TRUE;
 117                 for (int i=0; i<6; i++) {
 118                         result = gluProject(points3d[i][0],points3d[i][1],points3d[i][2],mm,pm,view,&points2d[i][0],&points2d[i][1],&points2d[i][2]);
 119                 }
 120                 //set the line width based on our distance from the runway
 121                 setLineWidth();
 122                 //Draw the runway lines on the HUD
 123                 glEnable(GL_LINE_STIPPLE);
 124                 glLineStipple(1,stippleOut);
 125                 anyLines =
 126                 drawLine(points3d[0],points3d[1],points2d[0],points2d[1]) | //draw top
 127                 drawLine(points3d[2],points3d[1],points2d[2],points2d[1]) | //draw right
 128                 drawLine(points3d[2],points3d[3],points2d[2],points2d[3]) | //draw bottom
 129                 drawLine(points3d[3],points3d[0],points2d[3],points2d[0]);  //draw left
 130                 glLineStipple(1,stippleCen);
 131                 anyLines |=     drawLine(points3d[5],points3d[4],points2d[5],points2d[4]); //draw center
 132                 //Check to see if arrow needs drawn
 133                 if ((!anyLines && drawIA) || drawIAAlways) {
 134                         drawArrow(); //draw indication arrow
 135                 }
 136                 //Restore the current view and any offsets
 137                 if (curr_view_id != 0) {
 138                         globals->get_viewmgr()->set_view(curr_view_id);
 139                         globals->get_viewmgr()->copyToCurrent();
 140                         curr_view->setHeadingOffset_deg(ho);
 141                         curr_view->setPitchOffset_deg(po);
 142                         curr_view->setGoalHeadingOffset_deg(gho);
 143                         curr_view->setGoalPitchOffset_deg(gpo);
 144                 }
 145                 //Set the camera back to the current view
 146                 ssgSetCamera((sgVec4 *)curr_view);
 147                 glPopAttrib();
 148         }//if not broken
 149 }
 150
 151 FGRunway runway_instr::get_active_runway() {
 152   FGEnvironment stationweather =
 153       ((FGEnvironmentMgr *)globals->get_subsystem("environment"))->getEnvironment();
 154   double hdg = stationweather.get_wind_from_heading_deg();
 155   FGRunway runway;
 156   globals->get_runways()->search( fgGetString("/sim/presets/airport-id"), int(hdg), &runway);
 157   return runway;
 158 }
 159
 160 void runway_instr::get_rwy_points(sgdVec3 *points3d) {
 161         static Point3D center = globals->get_scenery()->get_center();
 162
 163         //Get the current tile center
 164         Point3D currentCenter = globals->get_scenery()->get_center();
 165         Point3D tileCenter = currentCenter;
 166         if (center != currentCenter) //if changing tiles
 167                 tileCenter = center; //use last center
 168         double alt = current_aircraft.fdm_state->get_Runway_altitude()*SG_FEET_TO_METER;
 169         double length = (runway.length/2.0)*SG_FEET_TO_METER;
 170         double width = (runway.width/2.0)*SG_FEET_TO_METER;
 171         double frontLat,frontLon,backLat,backLon,az,tempLat,tempLon;
 172
 173         geo_direct_wgs_84(alt,runway.lat,runway.lon,runway.heading,length,&backLat,&backLon,&az);
 174         sgGeodToCart(backLat*SG_DEGREES_TO_RADIANS,backLon*SG_DEGREES_TO_RADIANS,alt,points3d[4]);
 175
 176         geo_direct_wgs_84(alt,runway.lat,runway.lon,runway.heading+180,length,&frontLat,&frontLon,&az);
 177         sgGeodToCart(frontLat*SG_DEGREES_TO_RADIANS,frontLon*SG_DEGREES_TO_RADIANS,alt,points3d[5]);
 178
 179         geo_direct_wgs_84(alt,backLat,backLon,runway.heading+90,width,&tempLat,&tempLon,&az);
 180         sgGeodToCart(tempLat*SG_DEGREES_TO_RADIANS,tempLon*SG_DEGREES_TO_RADIANS,alt,points3d[0]);
 181
 182         geo_direct_wgs_84(alt,backLat,backLon,runway.heading-90,width,&tempLat,&tempLon,&az);
 183         sgGeodToCart(tempLat*SG_DEGREES_TO_RADIANS,tempLon*SG_DEGREES_TO_RADIANS,alt,points3d[1]);
 184
 185         geo_direct_wgs_84(alt,frontLat,frontLon,runway.heading-90,width,&tempLat,&tempLon,&az);
 186         sgGeodToCart(tempLat*SG_DEGREES_TO_RADIANS,tempLon*SG_DEGREES_TO_RADIANS,alt,points3d[2]);
 187
 188         geo_direct_wgs_84(alt,frontLat,frontLon,runway.heading+90,width,&tempLat,&tempLon,&az);
 189         sgGeodToCart(tempLat*SG_DEGREES_TO_RADIANS,tempLon*SG_DEGREES_TO_RADIANS,alt,points3d[3]);
 190
 191         for(int i = 0; i < 6; i++)
 192         {
 193                 points3d[i][0] -= tileCenter.x();
 194                 points3d[i][1] -= tileCenter.y();
 195                 points3d[i][2] -= tileCenter.z();
 196         }
 197         center = currentCenter;
 198 }
 199
 200 bool runway_instr::drawLine(sgdVec3 a1, sgdVec3 a2, sgdVec3 point1, sgdVec3 point2) {
 201         sgdVec3 p1, p2;
 202         sgdCopyVec3(p1, point1);
 203         sgdCopyVec3(p2, point2);
 204         bool p1Inside = (p1[0]>=location.left && p1[0]<=location.right && p1[1]>=location.bottom && p1[1]<=location.top);
 205         bool p1Insight = (p1[2] >= 0.0 && p1[2] < 1.0);
 206         bool p1Valid = p1Insight && p1Inside;
 207         bool p2Inside = (p2[0]>=location.left && p2[0]<=location.right && p2[1]>=location.bottom && p2[1]<=location.top);
 208         bool p2Insight = (p2[2] >= 0.0 && p2[2] < 1.0);
 209         bool p2Valid = p2Insight && p2Inside;
 210
 211         if (p1Valid && p2Valid) { //Both project points are valid, draw the line
 212                 glBegin(GL_LINES);
 213                 glVertex2d(p1[0],p1[1]);
 214                 glVertex2d(p2[0],p2[1]);
 215                 glEnd();
 216         }
 217         else if (p1Valid) { //p1 is valid and p2 is not, calculate a new valid point
 218                 sgdVec3 vec = {a2[0]-a1[0], a2[1]-a1[1], a2[2]-a1[2]};
 219                 //create the unit vector
 220                 sgdScaleVec3(vec,1.0/sgdLengthVec3(vec));
 221                 sgdVec3 newPt;
 222                 sgdCopyVec3(newPt,a1);
 223                 sgdAddVec3(newPt,vec);
 224                 if (gluProject(newPt[0],newPt[1],newPt[2],mm,pm,view,&p2[0],&p2[1],&p2[2]) && (p2[2]>0&&p2[2]<1.0) ) {
 225                         boundPoint(p1,p2);
 226                         glBegin(GL_LINES);
 227                         glVertex2d(p1[0],p1[1]);
 228                         glVertex2d(p2[0],p2[1]);
 229                         glEnd();
 230                 }
 231         }
 232         else if (p2Valid) { //p2 is valid and p1 is not, calculate a new valid point
 233                 sgdVec3 vec = {a1[0]-a2[0], a1[1]-a2[1], a1[2]-a2[2]};
 234                 //create the unit vector
 235                 sgdScaleVec3(vec,1.0/sgdLengthVec3(vec));
 236                 sgdVec3 newPt;
 237                 sgdCopyVec3(newPt,a2);
 238                 sgdAddVec3(newPt,vec);
 239                 if (gluProject(newPt[0],newPt[1],newPt[2],mm,pm,view,&p1[0],&p1[1],&p1[2]) && (p1[2]>0&&p1[2]<1.0)) {
 240                         boundPoint(p2,p1);
 241                         glBegin(GL_LINES);
 242                         glVertex2d(p2[0],p2[1]);
 243                         glVertex2d(p1[0],p1[1]);
 244                         glEnd();
 245                 }
 246         }
 247         else if (p1Insight && p2Insight) { //both points are insight, but not inside
 248                 bool v = boundOutsidePoints(p1,p2);
 249                 if (v) {
 250                         glBegin(GL_LINES);
 251                                 glVertex2d(p1[0],p1[1]);
 252                                 glVertex2d(p2[0],p2[1]);
 253                         glEnd();
 254                 }
 255                 return v;
 256         }
 257         //else both points are not insight, don't draw anything
 258     return (p1Valid && p2Valid);
 259 }
 260
 261 void runway_instr::boundPoint(sgdVec3 v, sgdVec3 m) {
 262         double y = v[1];
 263         if(m[1] < v[1]) {
 264                 y = location.bottom;
 265         }
 266         else if(m[1] > v[1]) {
 267                 y = location.top;
 268         }
 269         if (m[0] == v[0]) {
 270                 m[1]=y;
 271                 return;  //prevent divide by zero
 272         }
 273         double slope = (m[1]-v[1])/(m[0]-v[0]);
 274         m[0] = (y-v[1])/slope + v[0];
 275         m[1] = y;
 276         if (m[0] < location.left) {
 277                 m[0] = location.left;
 278                 m[1] = slope * (location.left-v[0])+v[1];
 279         }
 280         else if (m[0] > location.right) {
 281                 m[0] = location.right;
 282                 m[1] = slope * (location.right-v[0])+v[1];
 283         }
 284 }
 285
 286 bool runway_instr::boundOutsidePoints(sgdVec3 v, sgdVec3 m) {
 287         bool pointsInvalid = (v[1]>location.top && m[1]>location.top) ||
 288                                (v[1]<location.bottom && m[1]<location.bottom) ||
 289                                            (v[0]>location.right && m[0]>location.right) ||
 290                                            (v[0]<location.left && m[0]<location.left);
 291         if (pointsInvalid)
 292                 return false;
 293         if (m[0] == v[0]) {//x's are equal, vertical line
 294                 if (m[1]>v[1]) {
 295                         m[1]=location.top;
 296                         v[1]=location.bottom;
 297                 }
 298                 else {
 299                         v[1]=location.top;
 300                         m[1]=location.bottom;
 301                 }
 302                 return true;
 303         }
 304         if (m[1] == v[1]) { //y's are equal, horizontal line
 305                 if (m[0] > v[0]) {
 306                         m[0] = location.right;
 307                         v[0] = location.left;
 308                 }
 309                 else {
 310                         v[0] = location.right;
 311                         m[0] = location.left;
 312                 }
 313                 return true;
 314         }
 315         double slope = (m[1]-v[1])/(m[0]-v[0]);
 316         double b = v[1]-(slope*v[0]);
 317         double y1 = slope * location.left + b;
 318         double y2 = slope * location.right + b;
 319         double x1 = (location.bottom - b) / slope;
 320         double x2 = (location.top - b) / slope;
 321         int counter = 0;
 322         if  (y1 >= location.bottom && y1 <= location.top) {
 323                 v[0] = location.left;
 324                 v[1] = y1;
 325                 counter++;
 326         }
 327         if (y2 >= location.bottom && y2 <= location.top) {
 328                 if (counter > 0) {
 329                         m[0] = location.right;
 330                         m[1] = y2;
 331                 }
 332                 else {
 333                         v[0] = location.right;
 334                         v[1] = y2;
 335                 }
 336                 counter++;
 337         }
 338         if (x1 >= location.left && x1 <= location.right) {
 339                 if (counter > 0) {
 340                         m[0] = x1;
 341                         m[1] = location.bottom;
 342                 }
 343                 else {
 344                         v[0] = x1;
 345                         v[1] = location.bottom;
 346                 }
 347                 counter++;
 348         }
 349         if (x2 >= location.left && x2 <= location.right) {
 350                 m[0] = x1;
 351                 m[1] = location.bottom;
 352                 counter++;
 353         }
 354         return (counter == 2);
 355 }
 356
 357 void runway_instr::drawArrow() {
 358         Point3D ac,rwy;
 359         ac.setlat(current_aircraft.fdm_state->get_Latitude_deg());
 360         ac.setlon(current_aircraft.fdm_state->get_Longitude_deg());
 361         rwy.setlat(runway.lat);
 362         rwy.setlon(runway.lon);
 363         float theta = GetHeadingFromTo(ac,rwy);
 364         theta -= fgGetDouble("/orientation/heading-deg");
 365         theta = -theta;
 366         glMatrixMode(GL_MODELVIEW);
 367         glPushMatrix();
 368         glTranslated((location.right+location.left)/2.0,(location.top+location.bottom)/2.0,0.0);
 369         glRotated(theta,0.0,0.0,1.0);
 370         glTranslated(0.0,arrowRad,0.0);
 371         glScaled(arrowScale,arrowScale,0.0);
 372         glBegin(GL_TRIANGLES);
 373                 glVertex2d(-5.0,12.5);
 374                 glVertex2d(0.0,25.0);
 375                 glVertex2d(5.0,12.5);
 376         glEnd();
 377         glBegin(GL_QUADS);
 378                 glVertex2d(-2.5,0.0);
 379                 glVertex2d(-2.5,12.5);
 380                 glVertex2d(2.5,12.5);
 381                 glVertex2d(2.5,0.0);
 382         glEnd();
 383         glPopMatrix();
 384 }
 385
 386 void runway_instr::setLineWidth() {
 387         //Calculate the distance from the runway, A
 388         double course, distance;
 389         calc_gc_course_dist(Point3D(runway.lon*SGD_DEGREES_TO_RADIANS, runway.lat*SGD_DEGREES_TO_RADIANS, 0.0),
 390                 Point3D(current_aircraft.fdm_state->get_Longitude(),current_aircraft.fdm_state->get_Latitude(), 0.0 ),
 391                 &course, &distance);
 392         distance *= SG_METER_TO_NM;
 393         //Get altitude above runway, B
 394         double alt_nm = get_agl();
 395         static const SGPropertyNode *startup_units_node
 396     = fgGetNode("/sim/startup/units");
 397         if (!strcmp(startup_units_node->getStringValue(), "feet"))
 398                 alt_nm *= SG_FEET_TO_METER*SG_METER_TO_NM;
 399         else
 400                 alt_nm *= SG_METER_TO_NM;
 401         //Calculate distance away from runway, C = v(A²+B²)
 402         distance = sqrt(alt_nm*alt_nm + distance*distance);
 403         if (distance < scaleDist)
 404                 glLineWidth( 1.0+( (lnScale-1)*( (scaleDist-distance)/scaleDist)));
 405         else
 406                 glLineWidth( 1.0 );
 407
 408 }
 409
 410 void runway_instr::setArrowRotationRadius(double radius) { arrowRad = radius; }
 411 void runway_instr::setArrowScale(double scale) { arrowScale = scale; }
 412 void runway_instr::setDrawArrow(bool draw) {drawIA = draw;}
 413 void runway_instr::setDrawArrowAlways(bool draw) {drawIAAlways = draw;}
 414 void runway_instr::setLineScale(double scale) {lnScale = scale;}
 415 void runway_instr::setScaleDist(double dist_m) {scaleDist = dist_m;}
 416 void runway_instr::setStippleOutline(unsigned short stipple) {stippleOut = stipple;}
 417 void runway_instr::setStippleCenterline(unsigned short stipple){stippleCen = stipple;}
 418