+// return the amount of heading needle deflection, returns a value
+// clamped to the range of ( -10 , 10 )
+double FGRadioStack::get_nav1_heading_needle_deflection() const {
+ double r;
+
+ if ( nav1_inrange ) {
+ r = nav1_heading - nav1_radial;
+ // cout << "Radial = " << nav1_radial
+ // << " Bearing = " << nav1_heading << endl;
+
+ while ( r > 180.0 ) { r -= 360.0;}
+ while ( r < -180.0 ) { r += 360.0;}
+ if ( fabs(r) > 90.0 ) {
+ r = ( r<0.0 ? -r-180.0 : -r+180.0 );
+ if ( nav1_loc ) {
+ r = -r;
+ }
+ }
+
+ // According to Robin Peel, the ILS is 4x more sensitive than a vor
+ if ( nav1_loc ) { r *= 4.0; }
+ if ( r < -10.0 ) { r = -10.0; }
+ if ( r > 10.0 ) { r = 10.0; }
+ } else {
+ r = 0.0;
+ }
+
+ return r;
+}
+
+// return the amount of heading needle deflection, returns a value
+// clamped to the range of ( -10 , 10 )
+double FGRadioStack::get_nav2_heading_needle_deflection() const {
+ double r;
+
+ if ( nav2_inrange ) {
+ r = nav2_heading - nav2_radial;
+ // cout << "Radial = " << nav2_radial
+ // << " Bearing = " << nav2_heading << endl;
+
+ while (r> 180.0) r-=360.0;
+ while (r<-180.0) r+=360.0;
+ if ( fabs(r) > 90.0 )
+ r = ( r<0.0 ? -r-180.0 : -r+180.0 );
+ // According to Robin Peel, the ILS is 4x more sensitive than a vor
+ if ( nav2_loc ) r *= 4.0;
+ if ( r < -10.0 ) r = -10.0;
+ if ( r > 10.0 ) r = 10.0;
+ } else {
+ r = 0.0;
+ }
+
+ return r;
+}
+
+// return the amount of glide slope needle deflection (.i.e. the
+// number of degrees we are off the glide slope * 5.0
+double FGRadioStack::get_nav1_gs_needle_deflection() const {
+ if ( nav1_inrange && nav1_has_gs ) {
+ double x = nav1_gs_dist;
+ double y = (FGBFI::getAltitude() - nav1_elev) * FEET_TO_METER;
+ double angle = atan2( y, x ) * RAD_TO_DEG;
+ return (nav1_target_gs - angle) * 5.0;
+ } else {
+ return 0.0;
+ }
+}
+
+
+// return the amount of glide slope needle deflection (.i.e. the
+// number of degrees we are off the glide slope * 5.0
+double FGRadioStack::get_nav2_gs_needle_deflection() const {
+ if ( nav2_inrange && nav2_has_gs ) {
+ double x = nav2_gs_dist;
+ double y = (FGBFI::getAltitude() - nav2_elev) * FEET_TO_METER;
+ double angle = atan2( y, x ) * RAD_TO_DEG;
+ return (nav2_target_gs - angle) * 5.0;
+ } else {
+ return 0.0;
+ }
+}
+
+