# ==============================================================================
# Boeing Navigation Display by Gijs de Rooy
# See: http://wiki.flightgear.org/Canvas_ND_Framework
# ==============================================================================
# This file makes use of the MapStructure framework, see: http://wiki.flightgear.org/Canvas_MapStructure
#
# Sooner or later, some parts will be revamped by coming up with a simple animation framework: http://wiki.flightgear.org/NavDisplay#mapping_vs._SVG_animation

##
# pseudo DSL-ish: use these as placeholders in the config hash  below
var ALWAYS = func 1;
var NOTHING = func nil;

##
# TODO: move ND-specific implementation details into this lookup hash
# so that other aircraft and ND types can be more easily supported
#
# any aircraft-specific ND behavior should be wrapped here,
# to isolate/decouple things in the generic NavDisplay class
#
# TODO: move this to an XML config file (maybe supporting SGCondition and/or SGStateMachine markup for the logic?)
#
var NDStyles = {
	##
	# this configures the 744 ND to help generalize the NavDisplay class itself
	'Boeing': {
		font_mapper: func(family, weight) {
			if( family == "Liberation Sans" and weight == "normal" )
				return "LiberationFonts/LiberationSans-Regular.ttf";
		},

		# where all the symbols are stored
		# TODO: SVG elements should be renamed to use boeing/airbus prefix
		# aircraft developers should all be editing the same ND.svg image
		# the code can deal with the differences now
		svg_filename: "Nasal/canvas/map/Images/boeingND.svg",
		##
		## this loads and configures existing layers (currently, *.layer files in Nasal/canvas/map)
		##


		# TODO: phase out isMapStructure flag once map.nas & *.draw files are killed
		layers: [
			# TODO: take z-indices from *.draw files -- now handled by MapStructure in the addLayer method.
			{ name:'FIX', isMapStructure:1, update_on:['toggle_display_mode','toggle_range','toggle_waypoints'],
				# FIXME: this is a really ugly place for controller code
				predicate: func(nd, layer) {
					# print("Running fix layer predicate");
					# toggle visibility here
					var visible=nd.get_switch('toggle_waypoints') and nd.in_mode('toggle_display_mode', ['MAP']) and (nd.rangeNm() <= 40);
					layer.group.setVisible( visible );
					if (visible) {
						#print("Updating MapStructure ND layer: FIX");
						# (Hopefully) smart update
						layer.update();
					}
				}, # end of layer update predicate
				'z-index': -3,
			}, # end of FIX layer

			# Should redraw every 10 seconds TODO: use new MapStructure/WXR here once that works properly (Gijs should check first!)
			{ name:'WXR', isMapStructure:1, update_on:[ {rate_hz: 0.1}, 'toggle_range','toggle_weather','toggle_display_mode'],
				predicate: func(nd, layer) {
					#print("Running storms predicate");
					var visible=nd.get_switch('toggle_weather') and nd.get_switch('toggle_display_mode') != "PLAN";
					layer.group.setVisible(visible);
					if (visible) {
						print("storms update requested! (timer issue when closing the dialog?)");
						layer.update(); 
					}
				}, # end of layer update predicate
				'z-index': -4,
			}, # end of storms/WXR layer

			{ name:'APS', isMapStructure:1, update_on:['toggle_display_mode'], 
				predicate: func(nd, layer) {
					var visible = nd.get_switch('toggle_display_mode') == "PLAN";
					layer.group.setVisible( visible );
					if (visible) {
						layer.update();
					}
				},
			},

			{ name:'APT', isMapStructure:1, update_on:['toggle_range','toggle_airports','toggle_display_mode'],
				predicate: func(nd, layer) {
					# toggle visibility here
					var visible=nd.get_switch('toggle_airports') and nd.in_mode('toggle_display_mode', ['MAP']);
					layer.group.setVisible( visible );
					if (visible) {
						#print("Updating MapStructure ND layer: APT");
						layer.update();
					}
				}, # end of layer update predicate
				'z-index': -1,
			}, # end of APT layer

			# Should distinct between low and high altitude navaids. Hiding above 40 NM for now, to prevent clutter/lag.
			{ name:'VOR', isMapStructure:1, update_on:['toggle_range','toggle_stations','toggle_display_mode'],
				# FIXME: this is a really ugly place for controller code
				predicate: func(nd, layer) {
					# toggle visibility here
					var visible = nd.get_switch('toggle_stations') and nd.in_mode('toggle_display_mode', ['MAP']) and (nd.rangeNm() <= 40);
					layer.group.setVisible( visible );
					if (visible) {
						#print("Updating MapStructure ND layer: VOR");
						layer.update();
					}
				}, # end of layer update predicate
				'z-index': -2,
			}, # end of VOR layer

			{ name:'DME', isMapStructure:1, update_on:['toggle_display_mode','toggle_range','toggle_stations'],
				# FIXME: this is a really ugly place for controller code
				predicate: func(nd, layer) {
					var visible = nd.get_switch('toggle_stations') and nd.in_mode('toggle_display_mode', ['MAP']) and (nd.rangeNm() <= 40);
					# toggle visibility here
					layer.group.setVisible( visible );
					if (visible) {
						#print("Updating MapStructure ND layer: DME");
						layer.update();
					}
				}, # end of layer update predicate
				'z-index': -2,
			}, # end of DME layer

			{ name:'TFC', isMapStructure:1, update_on:['toggle_range','toggle_traffic'],
				predicate: func(nd, layer) {
					var visible = nd.get_switch('toggle_traffic');
					layer.group.setVisible( visible );
					if (visible) {
						#print("Updating MapStructure ND layer: TFC");
						layer.update();
					}
				}, # end of layer update predicate
				'z-index': 4,
			}, # end of traffic layer

			{ name:'runway-nd', update_on:['toggle_range','toggle_display_mode'],
				predicate: func(nd, layer) {
					#print("runway-nd wants to be ported to MapStructure");
					var visible = (nd.rangeNm() <= 40) and getprop("autopilot/route-manager/active") and nd.in_mode('toggle_display_mode', ['MAP','PLAN']) ;
					if (visible)
						layer._model.init(); # clear & redraw
					layer._view.setVisible( visible );
				}, # end of layer update predicate
			}, # end of airports-nd layer

			{ name:'RTE', isMapStructure:1, update_on:['toggle_range','toggle_display_mode'],
				predicate: func(nd, layer) {
					var visible= (nd.in_mode('toggle_display_mode', ['MAP','PLAN']));
					layer.group.setVisible( visible );
					if (visible)
						layer.update();
				}, # end of layer update predicate
				'z-index': 1,
			}, # end of route layer
			{ name:'WPT', isMapStructure:1, update_on:['toggle_range','toggle_display_mode'],
				predicate: func(nd, layer) {
					var visible= (nd.in_mode('toggle_display_mode', ['MAP','PLAN']));
					layer.group.setVisible( visible );

					if (visible)
						layer.update();
				}, # end of layer update predicate
				'z-index': 2,
			}, # end of waypoint layer
			{ name:'ALT-profile', isMapStructure:1, update_on:['toggle_range','toggle_display_mode'],
				predicate: func(nd, layer) {
					var visible= (nd.in_mode('toggle_display_mode', ['MAP','PLAN']));
					layer.group.setVisible( visible );

					if (visible)
						layer.update();
				}, # end of layer update predicate
				'z-index': 3,
			}, # end of altitude profile layer

			## add other layers here, layer names must match the registered names as used in *.layer files for now
			## this will all change once we're using Philosopher's MapStructure framework

		], # end of vector with configured layers

		# This is where SVG elements are configured by providing "behavior" hashes, i.e. for animations

		# to animate each SVG symbol, specify behavior via callbacks (predicate, and true/false implementation)
		# SVG identifier, callback  etc
		# TODO: update_on([]), update_mode (update() vs. timers/listeners)
		# TODO: support putting symbols on specific layers
		features: [
			{
				# TODO: taOnly doesn't need to use getprop polling in update(), use a listener instead!
				id: 'taOnly', # the SVG ID
				impl: { # implementation hash
					init: func(nd, symbol), # for updateCenter stuff, called during initialization in the ctor
					predicate: func(nd) getprop("instrumentation/tcas/inputs/mode") == 2, # the condition
					is_true:   func(nd) nd.symbols.taOnly.show(), 			# if true, run this
					is_false:  func(nd) nd.symbols.taOnly.hide(), 			# if false, run this
				}, # end of taOnly  behavior/callbacks
			}, # end of taOnly
			{
				id: 'tas',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.aircraft_source.get_spd() > 100,
					is_true: func(nd) {
						nd.symbols.tas.setText(sprintf("%3.0f",nd.aircraft_source.get_spd() ));
						nd.symbols.tas.show();
					},
					is_false: func(nd) nd.symbols.tas.hide(),
				},
			},
			{
				id: 'tasLbl',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.aircraft_source.get_spd() > 100,
					is_true: func(nd) nd.symbols.tasLbl.show(),
					is_false: func(nd) nd.symbols.tasLbl.hide(),
				},
			},
			{
				id: 'ilsFreq',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.in_mode('toggle_display_mode', ['APP']),
					is_true: func(nd) {
						nd.symbols.ilsFreq.show();
						if(getprop("instrumentation/nav/in-range"))
							nd.symbols.ilsFreq.setText(getprop("instrumentation/nav/nav-id"));
						else
							nd.symbols.ilsFreq.setText(getprop("instrumentation/nav/frequencies/selected-mhz-fmt"));
					},
					is_false: func(nd) nd.symbols.ilsFreq.hide(),
				},
			},
			{
				id: 'ilsLbl',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.in_mode('toggle_display_mode', ['APP']),
					is_true: func(nd) {
						nd.symbols.ilsLbl.show();
					},
					is_false: func(nd) nd.symbols.ilsLbl.hide(),
				},
			},
			{
				id: 'wpActiveId',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) getprop("/autopilot/route-manager/wp/id") != nil and getprop("autopilot/route-manager/active")
						and nd.in_mode('toggle_display_mode', ['MAP','PLAN']),
					is_true: func(nd) {
						nd.symbols.wpActiveId.setText(getprop("/autopilot/route-manager/wp/id"));
						nd.symbols.wpActiveId.show();
					},
					is_false: func(nd) nd.symbols.wpActiveId.hide(),
				}, # of wpActiveId.impl
			}, # of wpActiveId
			{
				id: 'wpActiveDist',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) getprop("/autopilot/route-manager/wp/dist") != nil and getprop("autopilot/route-manager/active")
						and nd.in_mode('toggle_display_mode', ['MAP','PLAN']),
					is_true: func(nd) {
						nd.symbols.wpActiveDist.setText(sprintf("%3.01f",getprop("/autopilot/route-manager/wp/dist")));
						nd.symbols.wpActiveDist.show();
					},
					is_false: func(nd) nd.symbols.wpActiveDist.hide(),
				},
			},
			{
				id: 'wpActiveDistLbl',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) getprop("/autopilot/route-manager/wp/dist") != nil and getprop("autopilot/route-manager/active")
						and nd.in_mode('toggle_display_mode', ['MAP','PLAN']),
					is_true: func(nd) {
						nd.symbols.wpActiveDistLbl.show();
						if(getprop("/autopilot/route-manager/wp/dist") > 1000)
							nd.symbols.wpActiveDistLbl.setText("   NM");
					},
					is_false: func(nd) nd.symbols.wpActiveDistLbl.hide(),
				},
			},
			{
				id: 'eta',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) getprop("autopilot/route-manager/wp/eta") != nil and getprop("autopilot/route-manager/active")
						and nd.in_mode('toggle_display_mode', ['MAP','PLAN']),
					is_true: func(nd) {
						var etaSec = getprop("/sim/time/utc/day-seconds")+getprop("autopilot/route-manager/wp/eta-seconds");
						var h = math.floor(etaSec/3600);
						etaSec=etaSec-3600*h;
						var m = math.floor(etaSec/60);
						etaSec=etaSec-60*m;
						var s = etaSec/10;
						if (h>24) h=h-24;
						nd.symbols.eta.setText(sprintf("%02.0f%02.0f.%01.0fz",h,m,s));
						nd.symbols.eta.show();
					},
					is_false: func(nd) nd.symbols.eta.hide(),
				},  # of eta.impl
			}, # of eta
			{
				id: 'gsGroup',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.in_mode('toggle_display_mode', ['APP']),
					is_true: func(nd) {
						if(nd.get_switch('toggle_centered'))
							nd.symbols.gsGroup.setTranslation(0,0);
						else
							nd.symbols.gsGroup.setTranslation(0,150);
						nd.symbols.gsGroup.show();
					},
					is_false: func(nd) nd.symbols.gsGroup.hide(),
				},
			},
			{
				id: 'compassApp',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (nd.get_switch('toggle_centered') and nd.in_mode('toggle_display_mode', ['APP','VOR'])),
					is_true: func(nd) {
						if(nd.get_switch('toggle_true_north'))
							var hdg = nd.aircraft_source.get_trk_tru();
						else
							var hdg = nd.aircraft_source.get_trk_mag();
						nd.symbols.compassApp.setRotation(-hdg*D2R);
						nd.symbols.compassApp.show();
					},
					is_false: func(nd) nd.symbols.compassApp.hide(),
				},
			},
			{
				id: 'compassMapCtr',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (nd.get_switch('toggle_centered') and nd.in_mode('toggle_display_mode', ['MAP'])),
					is_true: func(nd) {
						if(nd.get_switch('toggle_true_north'))
							var hdg = nd.aircraft_source.get_trk_tru();
						else
							var hdg = nd.aircraft_source.get_trk_mag();
						nd.symbols.compassMapCtr.setRotation(-hdg*D2R);
						nd.symbols.compassMapCtr.show();
					},
					is_false: func(nd) nd.symbols.compassMapCtr.hide(),
				},
			},
			{
				id:'hdg',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.in_mode('toggle_display_mode', ['APP','MAP','VOR']),
					is_true: func(nd) {
						var hdgText = "";
						if((nd.in_mode('toggle_display_mode', ['MAP']) and nd.get_switch('toggle_display_type') == "CRT")
						    or (nd.get_switch('toggle_track_heading') and nd.get_switch('toggle_display_type') == "LCD"))
						{
							if(nd.get_switch('toggle_true_north'))
								hdgText = nd.aircraft_source.get_trk_tru();
							else
								hdgText = nd.aircraft_source.get_trk_mag();
						} else {
							if(nd.get_switch('toggle_true_north'))
								hdgText = nd.aircraft_source.get_hdg_tru();
							else
								hdgText = nd.aircraft_source.get_hdg_mag();
						}
						if(hdgText < 0.5) hdgText = 360 + hdgText;
						elsif(hdgText >= 360.5) hdgText = hdgText - 360;
						nd.symbols.hdg.setText(sprintf("%03.0f", hdgText));
					},
					is_false: NOTHING,
				},
			},
			{
				id:'hdgGroup',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.in_mode('toggle_display_mode', ['APP','MAP','VOR']),
					is_true: func(nd) {
						nd.symbols.hdgGroup.show();
						if(nd.get_switch('toggle_centered'))
							nd.symbols.hdgGroup.setTranslation(0,100);
						else
							nd.symbols.hdgGroup.setTranslation(0,0);
					},
					is_false: func(nd) nd.symbols.hdgGroup.hide(),
				},
			},
			{
				id:'gs',
				impl: {
					init: func(nd,symbol),
					common: func(nd) nd.symbols.gs.setText(sprintf("%3.0f",nd.aircraft_source.get_gnd_spd() )),
					predicate: func(nd) nd.aircraft_source.get_gnd_spd() >= 30,
					is_true: func(nd) {
						nd.symbols.gs.setFontSize(36);
					},
					is_false: func(nd) nd.symbols.gs.setFontSize(52),
				},
			},
			{
				id:'compass',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) ((nd.get_switch('toggle_centered') and !nd.in_mode('toggle_display_mode', ['PLAN'])) or nd.in_mode('toggle_display_mode', ['PLAN'])),
					is_true: func(nd) nd.symbols.compass.hide(),
					is_false: func(nd) {
						nd.symbols.compass.show();
						nd.symbols.compass.setRotation(-nd.userHdgTrk*D2R);
					},
				},
			},
			{
				id:'truMag',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.get_switch('toggle_true_north'),
					is_true: func(nd) nd.symbols.truMag.setText("TRU"),
					is_false: func(nd) nd.symbols.truMag.setText("MAG"),
				},
			},
			{
				id:'northUp',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.in_mode('toggle_display_mode', ['PLAN']),
					is_true: func(nd) nd.symbols.northUp.show(),
					is_false: func(nd) nd.symbols.northUp.hide(),
				},
			},
			{
				id:'planArcs',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.in_mode('toggle_display_mode', ['PLAN']),
					is_true: func(nd) nd.symbols.planArcs.show(),
					is_false: func(nd) nd.symbols.planArcs.hide(),
				},
			},
			{
				id:'aplSymMap',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (nd.in_mode('toggle_display_mode', ['APP','MAP','VOR'])  and !nd.get_switch('toggle_centered')),
					is_true: func(nd) nd.symbols.aplSymMap.show(),
					is_false: func(nd) nd.symbols.aplSymMap.hide(),
				},
			},
			{
				id:'aplSymMapCtr',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (nd.in_mode('toggle_display_mode', ['MAP'])  and nd.get_switch('toggle_centered')),
					is_true: func(nd) nd.symbols.aplSymMapCtr.show(),
					is_false: func(nd) nd.symbols.aplSymMapCtr.hide(),
				},
			},
			{
				id:'aplSymVor',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (nd.in_mode('toggle_display_mode', ['APP','VOR'])  and nd.get_switch('toggle_centered')),
					is_true: func(nd) nd.symbols.aplSymVor.show(),
					is_false: func(nd) nd.symbols.aplSymVor.hide(),
				},
			},
			{
				id:'rangeArcs',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) !nd.get_switch('toggle_centered') and nd.get_switch('toggle_rangearc'),
					is_true: func(nd) nd.symbols.rangeArcs.show(),
					is_false: func(nd) nd.symbols.rangeArcs.hide(),
				},
			},
			{
				id:'rangePln1',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.get_switch('toggle_display_mode') == "PLAN",
					is_true: func(nd) { 
						nd.symbols.rangePln1.show();
						nd.symbols.rangePln1.setText(sprintf("%3.0f",nd.rangeNm()));
					},
					is_false: func(nd) nd.symbols.rangePln1.hide(),
				},
			},
			{
				id:'rangePln2',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.get_switch('toggle_display_mode') == "PLAN",
					is_true: func(nd) { 
						nd.symbols.rangePln2.show();
						nd.symbols.rangePln2.setText(sprintf("%3.0f",nd.rangeNm()/2));
					},
					is_false: func(nd) nd.symbols.rangePln2.hide(),
				},
			},
			{
				id:'rangePln3',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.get_switch('toggle_display_mode') == "PLAN",
					is_true: func(nd) { 
						nd.symbols.rangePln3.show();
						nd.symbols.rangePln3.setText(sprintf("%3.0f",nd.rangeNm()/2));
					},
					is_false: func(nd) nd.symbols.rangePln3.hide(),
				},
			},
			{
				id:'rangePln4',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.get_switch('toggle_display_mode') == "PLAN",
					is_true: func(nd) { 
						nd.symbols.rangePln4.show();
						nd.symbols.rangePln4.setText(sprintf("%3.0f",nd.rangeNm()));
					},
					is_false: func(nd) nd.symbols.rangePln4.hide(),
				},
			},
			{
				id:'range',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) !nd.get_switch('toggle_centered'),
					is_true: func(nd) { 
						nd.symbols.range.setText(sprintf("%3.0f",nd.rangeNm()/2));
					},
					is_false: func(nd) nd.symbols.rangePln4.hide(),
				},
			},
			{
				id:'rangeCtr1',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (nd.get_switch('toggle_centered') and nd.in_mode('toggle_display_mode', ['APP','MAP','VOR'])),
					is_true: func(nd) {
						nd.symbols.rangeCtr1.show();
						nd.symbols.rangeCtr1.setText(sprintf("%g",nd.rangeNm()/4));
					},
					is_false: func(nd) nd.symbols.rangeCtr1.hide(),
				},
			},
			{
				id:'rangeCtr2',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (nd.get_switch('toggle_centered') and nd.in_mode('toggle_display_mode', ['APP','MAP','VOR'])),
					is_true: func(nd) { 
						nd.symbols.rangeCtr2.show();
						nd.symbols.rangeCtr2.setText(sprintf("%g",nd.rangeNm()/4));
					},
					is_false: func(nd) nd.symbols.rangeCtr2.hide(),
				},
			},
			{
				id:'altArc',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (!nd.get_switch('toggle_centered') and nd.in_mode('toggle_display_mode', ['MAP'])),
					is_true: func(nd) { 
						var altDiff = (getprop("autopilot/settings/target-altitude-ft") or 0)-(getprop("instrumentation/altimeter/indicated-altitude-ft") or 0);
						if (abs(altDiff) > 50 and altDiff/nd.aircraft_source.get_vspd() > 0) {
							var altRangeNm = altDiff/nd.aircraft_source.get_vspd()*nd.aircraft_source.get_gnd_spd()*KT2MPS*M2NM;
							if(altRangeNm > 1) {
								var altRangePx = (350/nd.rangeNm())*altRangeNm;
								if (altRangePx > 700)
									altRangePx = 700;
								nd.symbols.altArc.setTranslation(0,-altRangePx);
							}
							nd.symbols.altArc.show();
						} else
							nd.symbols.altArc.hide();
					},
					is_false: func(nd) nd.symbols.altArc.hide(),
				},
			},
			{
				id:'altArcCtr',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (nd.get_switch('toggle_centered') and nd.in_mode('toggle_display_mode', ['MAP'])),
					is_true: func(nd) { 
						var altDiff = (getprop("autopilot/settings/target-altitude-ft") or 0)-(getprop("instrumentation/altimeter/indicated-altitude-ft") or 0);
						if (abs(altDiff) > 50 and altDiff/nd.aircraft_source.get_vspd() > 0) {
							var altRangeNm = altDiff/nd.aircraft_source.get_vspd()*nd.aircraft_source.get_gnd_spd()*KT2MPS*M2NM;
							if(altRangeNm > 1) {
								var altRangePx = (175/nd.rangeNm())*altRangeNm;
								if (altRangePx > 350)
									altRangePx = 350;
								nd.symbols.altArcCtr.setTranslation(0,-altRangePx);
							}
							nd.symbols.altArcCtr.show();
						} else
							nd.symbols.altArcCtr.hide();
					},
					is_false: func(nd) nd.symbols.altArcCtr.hide(),
				},
			},
			{
				id:'crsLbl',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.in_mode('toggle_display_mode', ['APP','VOR']),
					is_true: func(nd) nd.symbols.crsLbl.show(),
					is_false: func(nd) nd.symbols.crsLbl.hide(),
				},
			},
			{
				id:'crs',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.in_mode('toggle_display_mode', ['APP','VOR']),
					is_true: func(nd) {
						nd.symbols.crs.show();
						if(getprop("instrumentation/nav/radials/selected-deg") != nil)
							nd.symbols.crs.setText(sprintf("%03.0f",getprop("instrumentation/nav/radials/selected-deg")));
					},
					is_false: func(nd) nd.symbols.crs.hide(),
				},
			},
			{
				id:'dmeLbl',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.in_mode('toggle_display_mode', ['APP','VOR']),
					is_true: func(nd) nd.symbols.dmeLbl.show(),
					is_false: func(nd) nd.symbols.dmeLbl.hide(),
				},
			},
			{
				id:'dme',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.in_mode('toggle_display_mode', ['APP','VOR']),
					is_true: func(nd) {
						nd.symbols.dme.show();
						if(getprop("instrumentation/dme/in-range"))
							nd.symbols.dme.setText(sprintf("%3.1f",getprop("instrumentation/dme/indicated-distance-nm")));
					},
					is_false: func(nd) nd.symbols.dme.hide(),
				},
			},
			{
				id:'trkInd2',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (nd.in_mode('toggle_display_mode', ['APP','VOR']) and nd.get_switch('toggle_centered')),
					is_true: func(nd) { 
						if (nd.get_switch('toggle_track_heading') and nd.get_switch('toggle_display_type') == "LCD")
							nd.symbols.trkInd2.setRotation(0);
						else
							nd.symbols.trkInd2.setRotation((nd.userTrk-nd.userHdg)*D2R);
						nd.symbols.trkInd2.show();
					},
					is_false: func(nd) nd.symbols.trkInd2.hide(),
				},
			},
			{
				id:'trkIndMapCtr',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (nd.in_mode('toggle_display_mode', ['MAP']) and nd.get_switch('toggle_centered')),
					is_true: func(nd) {
						if (nd.get_switch('toggle_display_type') == "CRT" or (nd.get_switch('toggle_track_heading') and nd.get_switch('toggle_display_type') == "LCD"))
							nd.symbols.trkIndMapCtr.setRotation(0);
						else
							nd.symbols.trkIndMapCtr.setRotation((nd.userTrk-nd.userHdg)*D2R);
						nd.symbols.trkIndMapCtr.show();
					},
					is_false: func(nd) nd.symbols.trkIndMapCtr.hide(),
				},
			},
			{
				id:'vorCrsPtr',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (nd.in_mode('toggle_display_mode', ['APP','VOR']) and !nd.get_switch('toggle_centered')),
					is_true: func(nd) {
						nd.symbols.vorCrsPtr.show();
						if((nd.in_mode('toggle_display_mode', ['MAP']) and nd.get_switch('toggle_display_type') == "CRT")
						    or (nd.get_switch('toggle_track_heading') and nd.get_switch('toggle_display_type') == "LCD"))
							nd.symbols.vorCrsPtr.setRotation((getprop("instrumentation/nav/radials/selected-deg")-nd.aircraft_source.get_trk_mag())*D2R);
						else
							nd.symbols.vorCrsPtr.setRotation((getprop("instrumentation/nav/radials/selected-deg")-nd.aircraft_source.get_hdg_mag())*D2R);
					},
					is_false: func(nd) nd.symbols.vorCrsPtr.hide(),
				},
			},
			{
				id:'vorCrsPtr2',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (nd.in_mode('toggle_display_mode', ['APP','VOR']) and nd.get_switch('toggle_centered')),
					is_true: func(nd) {
						nd.symbols.vorCrsPtr2.show();
						if((nd.in_mode('toggle_display_mode', ['MAP']) and nd.get_switch('toggle_display_type') == "CRT")
						    or (nd.get_switch('toggle_track_heading') and nd.get_switch('toggle_display_type') == "LCD"))
							nd.symbols.vorCrsPtr2.setRotation((getprop("instrumentation/nav/radials/selected-deg")-nd.aircraft_source.get_trk_mag())*D2R);
						else
							nd.symbols.vorCrsPtr2.setRotation((getprop("instrumentation/nav/radials/selected-deg")-nd.aircraft_source.get_hdg_mag())*D2R);
					},
					is_false: func(nd) nd.symbols.vorCrsPtr2.hide(),
				},
			},
			{
				id: 'gsDiamond',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) nd.in_mode('toggle_display_mode', ['APP']) and getprop("instrumentation/nav/gs-in-range"),
					is_true: func(nd) {
						var gs_deflection = getprop("instrumentation/nav/gs-needle-deflection-norm");
						if(gs_deflection != nil)
							nd.symbols.gsDiamond.setTranslation(gs_deflection*150,0);
						if(abs(gs_deflection) < 0.99)
							nd.symbols.gsDiamond.setColorFill(1,0,1,1);
						else
							nd.symbols.gsDiamond.setColorFill(0,0,0,1);
					},
					is_false: func(nd) nd.symbols.gsGroup.hide(),
				},
			},
			{
				id:'locPtr',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (nd.in_mode('toggle_display_mode', ['APP','VOR']) and !nd.get_switch('toggle_centered') and getprop("instrumentation/nav/in-range")),
					is_true: func(nd) {
						nd.symbols.locPtr.show();
						var deflection = getprop("instrumentation/nav/heading-needle-deflection-norm");
						nd.symbols.locPtr.setTranslation(deflection*150,0);
						if(abs(deflection) < 0.99)
							nd.symbols.locPtr.setColorFill(1,0,1,1);
						else
							nd.symbols.locPtr.setColorFill(0,0,0,1);
					},
					is_false: func(nd) nd.symbols.locPtr.hide(),
				},
			},
			{
				id:'locPtr2',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (nd.in_mode('toggle_display_mode', ['APP','VOR']) and nd.get_switch('toggle_centered') and getprop("instrumentation/nav/in-range")),
					is_true: func(nd) {
						nd.symbols.locPtr2.show();
						var deflection = getprop("instrumentation/nav/heading-needle-deflection-norm");
						nd.symbols.locPtr2.setTranslation(deflection*150,0);
						if(abs(deflection) < 0.99)
							nd.symbols.locPtr2.setColorFill(1,0,1,1);
						else
							nd.symbols.locPtr2.setColorFill(0,0,0,1);
					},
					is_false: func(nd) nd.symbols.locPtr2.hide(),
				},
			},
			{
				id:'wind',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (nd.aircraft_source.get_spd() > 100 and getprop("environment/wind-speed-kt") > 6),
					is_true: func(nd) {
						var windDir = getprop("environment/wind-from-heading-deg");
						if(!nd.get_switch('toggle_true_north'))
							windDir = windDir - getprop("environment/magnetic-variation-deg");
						if(windDir < 0.5) windDir = 360 + windDir;
						elsif(windDir >= 360.5) windDir = windDir - 360;
						nd.symbols.wind.setText(sprintf("%03.0f / %02.0f",windDir,getprop("environment/wind-speed-kt")));
						nd.symbols.wind.show();
					},
					is_false: func(nd) nd.symbols.wind.hide(),
				},
			},
			{
				id:'windArrow',
				impl: {
					init: func(nd,symbol),
					predicate: func(nd) (!(nd.in_mode('toggle_display_mode', ['PLAN']) and (nd.get_switch('toggle_display_type') == "LCD")) and nd.aircraft_source.get_spd() > 100 and getprop("environment/wind-speed-kt") > 6),
					is_true: func(nd) {
						nd.symbols.windArrow.show();
						var windArrowRot = getprop("environment/wind-from-heading-deg");
						if((nd.in_mode('toggle_display_mode', ['MAP','PLAN']) and nd.get_switch('toggle_display_type') == "CRT")
						    or (nd.get_switch('toggle_track_heading') and nd.get_switch('toggle_display_type') == "LCD"))
								windArrowRot = windArrowRot - nd.aircraft_source.get_trk_mag();
							else
								windArrowRot = windArrowRot - nd.aircraft_source.get_hdg_mag();
						nd.symbols.windArrow.setRotation(windArrowRot*D2R);
					},
					is_false: func(nd) nd.symbols.windArrow.hide(),
				},
			},

		], # end of vector with features


	}, # end of Boeing style
#####
##
## add support for other aircraft/ND types and styles here (Airbus etc)
## or move to other files.
##
## see: http://wiki.flightgear.org/NavDisplay#Custom_ND_Styles
## and: http://wiki.flightgear.org/NavDisplay#Adding_new_features

}; # end of NDStyles