+
+void
+wxRadarBg::update_tacan()
+{
+ // draw TACAN symbol
+ int mode = _radar_mode_control_node->getIntValue();
+ bool inRange = _tacan_in_range_node->getBoolValue();
+
+ if (mode != 1 || !inRange)
+ return;
+
+ float size = 600 * UNIT;
+ float radius = _tacan_distance_node->getFloatValue() * _scale;
+ float angle = _tacan_bearing_node->getFloatValue() * SG_DEGREES_TO_RADIANS
+ + _angle_offset;
+
+ const osg::Vec2f texBase(1 * UNIT, 3 * UNIT);
+ osg::Matrixf m(osg::Matrixf::scale(size, size, 1.0f)
+ * wxRotate(-angle)
+ * osg::Matrixf::translate(0.0f, radius, 0.0f)
+ * wxRotate(angle) * _centerTrans);
+ addQuad(_vertices, _texCoords, m, texBase);
+
+ //SG_LOG(SG_INSTR, SG_DEBUG, "Radar: drawing TACAN"
+ // << " dist=" << radius
+ // << " view_heading=" << _view_heading * SG_RADIANS_TO_DEGREES
+ // << " bearing=" << angle * SG_RADIANS_TO_DEGREES
+ // << " x=" << x << " y="<< y
+ // << " size=" << size);
+}
+
+
+void
+wxRadarBg::update_heading_marker()
+{
+ if (!_radar_hdg_marker_node->getBoolValue())
+ return;
+
+ const osg::Vec2f texBase(2 * UNIT, 3 * UNIT);
+ float size = 600 * UNIT;
+ osg::Matrixf m(osg::Matrixf::scale(size, size, 1.0f)
+ * wxRotate(_view_heading + _angle_offset));
+
+ m *= _centerTrans;
+ addQuad(_vertices, _texCoords, m, texBase);
+
+ //SG_LOG(SG_INSTR, SG_DEBUG, "Radar: drawing heading marker"
+ // << " x,y " << x <<","<< y
+ // << " dist" << dist
+ // << " view_heading" << _view_heading * SG_RADIANS_TO_DEGREES
+ // << " heading " << iradarEcho->heading * SG_RADIANS_TO_DEGREES
+ // << " angle " << angle * SG_RADIANS_TO_DEGREES);
+}
+
+
+void
+wxRadarBg::center_map()
+{
+ _lat = _user_lat_node->getDoubleValue();
+ _lon = _user_lon_node->getDoubleValue();
+ _x_offset = _y_offset = 0;
+}
+
+
+void
+wxRadarBg::apply_map_offset()
+{
+ double lat = _user_lat_node->getDoubleValue();
+ double lon = _user_lon_node->getDoubleValue();
+ double bearing, distance, az2;
+ geo_inverse_wgs_84(_lat, _lon, lat, lon, &bearing, &az2, &distance);
+ distance *= SG_METER_TO_NM * _scale;
+ bearing *= SG_DEGREES_TO_RADIANS;
+ _x_offset += sin(bearing) * distance;
+ _y_offset += cos(bearing) * distance;
+ _lat = lat;
+ _lon = lon;
+}
+
+
+bool
+wxRadarBg::withinRadarHorizon(double user_alt, double alt, double range_nm)
+{
+ // Radar Horizon = 1.23(ht^1/2 + hr^1/2),
+ //don't allow negative altitudes (an approximation - yes altitudes can be negative)
+ // Allow antenna ht to be set, but only on ground
+ _antenna_ht = _Instrument->getDoubleValue("antenna-ht-ft");
+
+ if (user_alt <= 0)
+ user_alt = _antenna_ht;
+
+ if (alt <= 0)
+ alt = 0; // to allow some vertical extent of target
+
+ double radarhorizon = 1.23 * (sqrt(alt) + sqrt(user_alt));
+// SG_LOG(SG_INSTR, SG_ALERT, "Radar: radar horizon " << radarhorizon);
+ return radarhorizon >= range_nm;
+}
+
+
+bool
+wxRadarBg::inRadarRange(double sigma, double range_nm)
+{
+ //The Radar Equation:
+ //
+ // MaxRange^4 = (TxPower * AntGain^2 * lambda^2 * sigma)/((constant) * MDS)
+ //
+ // Where (constant) = (4*pi)3 and MDS is the Minimum Detectable Signal power.
+ //
+ // For a given radar we can assume that the only variable is sigma,
+ // the target radar cross section.
+ //
+ // Here, we will use a normalised rcs (sigma) for a standard taget and assume that this
+ // will provide a maximum range of 35nm;
+ //
+ // TODO - make the maximum range adjustable at runtime
+
+ double constant = _radar_ref_rng;
+
+ if (constant <= 0)
+ constant = 35;
+
+ double maxrange = constant * pow(sigma, 0.25);
+ //SG_LOG(SG_INSTR, SG_DEBUG, "Radar: max range " << maxrange);
+ return maxrange >= range_nm;
+}
+
+
+void
+wxRadarBg::calcRangeBearing(double lat, double lon, double lat2, double lon2,
+ double &range, double &bearing) const
+{
+ // calculate the bearing and range of the second pos from the first
+ double az2, distance;
+ geo_inverse_wgs_84(lat, lon, lat2, lon2, &bearing, &az2, &distance);
+ range = distance *= SG_METER_TO_NM;
+}
+
+
+float
+wxRadarBg::calcRelBearing(float bearing, float heading)
+{
+ float angle = bearing - heading;
+
+ if (angle >= SG_PI)
+ angle -= 2.0 * SG_PI;
+
+ if (angle < -SG_PI)
+ angle += 2.0 * SG_PI;
+
+ return angle;
+}
+
+float
+wxRadarBg::calcRelBearingDeg(float bearing, float heading)
+{
+ float angle = bearing - heading;
+
+ if (angle >= 180)
+ return angle -= 360;
+
+ if (angle < -180)
+ return angle += 360;
+
+ return angle;
+}
+
+
+void
+wxRadarBg::updateFont()
+{
+ float red = _font_node->getFloatValue("color/red");
+ float green = _font_node->getFloatValue("color/green");
+ float blue = _font_node->getFloatValue("color/blue");
+ float alpha = _font_node->getFloatValue("color/alpha");
+ _font_color.set(red, green, blue, alpha);
+
+ _font_size = _font_node->getFloatValue("size");
+ _font_spacing = _font_size * _font_node->getFloatValue("line-spacing");
+ string path = _font_node->getStringValue("name", DEFAULT_FONT);
+
+ SGPath tpath;
+ if (path[0] != '/') {
+ tpath = globals->get_fg_root();
+ tpath.append("Fonts");
+ tpath.append(path);
+ } else {
+ tpath = path;
+ }
+
+#if (FG_OSG_VERSION >= 21000)
+ osg::ref_ptr<osgDB::ReaderWriter::Options> fontOptions = new osgDB::ReaderWriter::Options("monochrome");
+ osg::ref_ptr<osgText::Font> font = osgText::readFontFile(tpath.c_str(), fontOptions.get());
+#else
+ osg::ref_ptr<osgText::Font> font = osgText::readFontFile(tpath.c_str());
+#endif
+
+ if (font != 0) {
+ _font = font;
+ _font->setMinFilterHint(osg::Texture::NEAREST);
+ _font->setMagFilterHint(osg::Texture::NEAREST);
+ _font->setGlyphImageMargin(0);
+ _font->setGlyphImageMarginRatio(0);
+ }
+
+ for (int i=0;i<4;i++)
+ {
+ const float defaultColors[4][3] = {{0,1,1},{0,1,1},{1,0.5,0},{1,0,0}};
+ SGPropertyNode_ptr color_node = _font_node->getNode("tcas/color",i,true);
+ float red = color_node->getFloatValue("red",defaultColors[i][0]);
+ float green = color_node->getFloatValue("green",defaultColors[i][1]);
+ float blue = color_node->getFloatValue("blue",defaultColors[i][2]);
+ float alpha = color_node->getFloatValue("alpha",1);
+ _tcas_colors[i]=osg::Vec4(red, green, blue, alpha);
+ }
+}
+
+void
+wxRadarBg::valueChanged(SGPropertyNode*)
+{
+ updateFont();
+ _time = _interval;
+}
+