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