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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 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) :
  45     instr_item(x, y, width, height, NULL, scale_data, 0, working)
  46 {
  47     stippleOut=0xFFFF;
  48     stippleCen=0xFFFF;
  49     arrowScale = 1.0;
  50     arrowRad = 0.0;
  51     view[0] = 0;
  52     view[1] = 0;
  53     view[2] = 640;
  54     view[3] = 480;
  55     center.x = view[2]>>1;
  56     center.y = view[3]>>1;
  57     location.left = center.x-(width>>1)+x;
  58     location.right = center.x+(width>>1)+x;
  59     location.bottom = center.y-(height>>1)+y;
  60     location.top = center.y+(height>>1)+y;
  61     cockpit_view = globals->get_viewmgr()->get_view(0);
  62     default_heading = fgGetDouble("/sim/view[0]/config/pitch-heading-deg",0.0);
  63     default_pitch = fgGetDouble("/sim/view[0]/config/pitch-pitch-deg",0.0);
  64 }
  65
  66
  67 void runway_instr::draw() {
  68     if (!is_broken() && get_active_runway(runway)) {
  69         glPushAttrib(GL_LINE_STIPPLE | GL_LINE_STIPPLE_PATTERN | GL_LINE_WIDTH);
  70         float modelView[4][4],projMat[4][4];
  71         bool anyLines;
  72         //Get the current view
  73         FGViewer* curr_view = globals->get_viewmgr()->get_current_view();
  74         int curr_view_id = globals->get_viewmgr()->get_current();
  75         double gpo = curr_view->getGoalPitchOffset_deg();
  76         double gho = curr_view->getGoalHeadingOffset_deg();
  77         double po = curr_view->getPitchOffset_deg();
  78         double ho = curr_view->getHeadingOffset_deg();
  79
  80         double yaw = -(cockpit_view->getHeadingOffset_deg()-default_heading)*SG_DEGREES_TO_RADIANS;
  81         double pitch = (cockpit_view->getPitchOffset_deg()-default_pitch)*SG_DEGREES_TO_RADIANS;
  82         //double roll = fgGetDouble("/sim/view[0]/config/roll-offset-deg",0.0) //TODO: adjust for default roll offset
  83         double sPitch = sin(pitch), cPitch = cos(pitch),
  84                sYaw = sin(yaw), cYaw = cos(yaw);
  85
  86         //Assuming that the "Cockpit View" is always at position zero!!!
  87         if (curr_view_id != 0) {
  88             globals->get_viewmgr()->set_view(0);
  89             globals->get_viewmgr()->copyToCurrent();
  90         }
  91         //Set the camera to the cockpit view to get the view of the runway from the cockpit
  92         ssgSetCamera((sgVec4 *)cockpit_view->get_VIEW());
  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
 152 bool runway_instr::get_active_runway(FGRunway& runway) {
 153   FGEnvironment stationweather =
 154       ((FGEnvironmentMgr *)globals->get_subsystem("environment"))->getEnvironment();
 155   double hdg = stationweather.get_wind_from_heading_deg();
 156   return globals->get_runways()->search( fgGetString("/sim/presets/airport-id"), int(hdg), &runway);
 157 }
 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         points3d[i][0] -= tileCenter.x();
 193         points3d[i][1] -= tileCenter.y();
 194         points3d[i][2] -= tileCenter.z();
 195     }
 196     center = currentCenter;
 197 }
 198
 199
 200 bool runway_instr::drawLine(const sgdVec3& a1, const sgdVec3& a2, const sgdVec3& point1, const 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
 262 void runway_instr::boundPoint(const sgdVec3& v, sgdVec3& m) {
 263     double y = v[1];
 264     if (m[1] < v[1])
 265         y = location.bottom;
 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
 274     double slope = (m[1]-v[1])/(m[0]-v[0]);
 275     m[0] = (y-v[1])/slope + v[0];
 276     m[1] = y;
 277
 278     if (m[0] < location.left) {
 279         m[0] = location.left;
 280         m[1] = slope * (location.left-v[0])+v[1];
 281
 282     } else if (m[0] > location.right) {
 283         m[0] = location.right;
 284         m[1] = slope * (location.right-v[0])+v[1];
 285     }
 286 }
 287
 288
 289 bool runway_instr::boundOutsidePoints(sgdVec3& v, sgdVec3& m) {
 290     bool pointsInvalid = (v[1]>location.top && m[1]>location.top) ||
 291                          (v[1]<location.bottom && m[1]<location.bottom) ||
 292                          (v[0]>location.right && m[0]>location.right) ||
 293                          (v[0]<location.left && m[0]<location.left);
 294     if (pointsInvalid)
 295         return false;
 296
 297     if (m[0] == v[0]) {//x's are equal, vertical line
 298         if (m[1]>v[1]) {
 299             m[1]=location.top;
 300             v[1]=location.bottom;
 301         } else {
 302             v[1]=location.top;
 303             m[1]=location.bottom;
 304         }
 305         return true;
 306     }
 307
 308     if (m[1] == v[1]) { //y's are equal, horizontal line
 309         if (m[0] > v[0]) {
 310             m[0] = location.right;
 311             v[0] = location.left;
 312         } else {
 313             v[0] = location.right;
 314             m[0] = location.left;
 315         }
 316         return true;
 317     }
 318
 319     double slope = (m[1]-v[1])/(m[0]-v[0]);
 320     double b = v[1]-(slope*v[0]);
 321     double y1 = slope * location.left + b;
 322     double y2 = slope * location.right + b;
 323     double x1 = (location.bottom - b) / slope;
 324     double x2 = (location.top - b) / slope;
 325     int counter = 0;
 326
 327     if  (y1 >= location.bottom && y1 <= location.top) {
 328         v[0] = location.left;
 329         v[1] = y1;
 330         counter++;
 331     }
 332
 333     if (y2 >= location.bottom && y2 <= location.top) {
 334         if (counter > 0) {
 335             m[0] = location.right;
 336             m[1] = y2;
 337         } else {
 338             v[0] = location.right;
 339             v[1] = y2;
 340         }
 341         counter++;
 342     }
 343
 344     if (x1 >= location.left && x1 <= location.right) {
 345         if (counter > 0) {
 346             m[0] = x1;
 347             m[1] = location.bottom;
 348         } else {
 349             v[0] = x1;
 350             v[1] = location.bottom;
 351         }
 352         counter++;
 353     }
 354
 355     if (x2 >= location.left && x2 <= location.right) {
 356         m[0] = x1;
 357         m[1] = location.bottom;
 358         counter++;
 359     }
 360     return (counter == 2);
 361 }
 362
 363 void runway_instr::drawArrow() {
 364     Point3D ac(0.0), rwy(0.0);
 365     ac.setlat(current_aircraft.fdm_state->get_Latitude_deg());
 366     ac.setlon(current_aircraft.fdm_state->get_Longitude_deg());
 367     rwy.setlat(runway._lat);
 368     rwy.setlon(runway._lon);
 369     float theta = GetHeadingFromTo(ac,rwy);
 370     theta -= fgGetDouble("/orientation/heading-deg");
 371     theta = -theta;
 372     glMatrixMode(GL_MODELVIEW);
 373     glPushMatrix();
 374     glTranslated((location.right+location.left)/2.0,(location.top+location.bottom)/2.0,0.0);
 375     glRotated(theta,0.0,0.0,1.0);
 376     glTranslated(0.0,arrowRad,0.0);
 377     glScaled(arrowScale,arrowScale,0.0);
 378
 379     glBegin(GL_TRIANGLES);
 380     glVertex2d(-5.0,12.5);
 381     glVertex2d(0.0,25.0);
 382     glVertex2d(5.0,12.5);
 383     glEnd();
 384
 385     glBegin(GL_QUADS);
 386     glVertex2d(-2.5,0.0);
 387     glVertex2d(-2.5,12.5);
 388     glVertex2d(2.5,12.5);
 389     glVertex2d(2.5,0.0);
 390     glEnd();
 391     glPopMatrix();
 392 }
 393
 394 void runway_instr::setLineWidth() {
 395     //Calculate the distance from the runway, A
 396     double course, distance;
 397     calc_gc_course_dist(Point3D(runway._lon*SGD_DEGREES_TO_RADIANS, runway._lat*SGD_DEGREES_TO_RADIANS, 0.0),
 398         Point3D(current_aircraft.fdm_state->get_Longitude(),current_aircraft.fdm_state->get_Latitude(), 0.0 ),
 399         &course, &distance);
 400     distance *= SG_METER_TO_NM;
 401     //Get altitude above runway, B
 402     double alt_nm = get_agl();
 403     static const SGPropertyNode *startup_units_node
 404     = fgGetNode("/sim/startup/units");
 405
 406     if (!strcmp(startup_units_node->getStringValue(), "feet"))
 407         alt_nm *= SG_FEET_TO_METER*SG_METER_TO_NM;
 408     else
 409         alt_nm *= SG_METER_TO_NM;
 410
 411     //Calculate distance away from runway, C = v(A²+B²)
 412     distance = sqrt(alt_nm*alt_nm + distance*distance);
 413     if (distance < scaleDist)
 414         glLineWidth( 1.0+( (lnScale-1)*( (scaleDist-distance)/scaleDist)));
 415     else
 416         glLineWidth( 1.0 );
 417
 418 }
 419
 420 void runway_instr::setArrowRotationRadius(double radius) { arrowRad = radius; }
 421 void runway_instr::setArrowScale(double scale) { arrowScale = scale; }
 422 void runway_instr::setDrawArrow(bool draw) {drawIA = draw;}
 423 void runway_instr::setDrawArrowAlways(bool draw) {drawIAAlways = draw;}
 424 void runway_instr::setLineScale(double scale) {lnScale = scale;}
 425 void runway_instr::setScaleDist(double dist_m) {scaleDist = dist_m;}
 426 void runway_instr::setStippleOutline(unsigned short stipple) {stippleOut = stipple;}
 427 void runway_instr::setStippleCenterline(unsigned short stipple){stippleCen = stipple;}
 428