fgdata/Aircraft/Generic/radardist.nas

### Radar Visibility Calculator

# Jettoo (glazmax) and xiii (Alexis)

# my_maxrange(myaircraft): finds our own aircraft max radar range in a table.
# Returns my_radarcorr in kilometers.

# radis(i, my_radarcorr): find multiplayer[i], its Radar Cross Section (RCS),
# applies factor upon our altitude, shorter radar detection distance (due to air
# turbulence), then factor upon its altitude above ground, and finaly computes if
# it is detectable given our radar range.
# Returns 1 if detectable, 0 if not.



var FT2M = 0.3048;
var NM2KM = 1.852;


var my_maxrange = func(myaircraft) {
	var myacname = aircraftData[myaircraft];
	if (myacname == nil){
		myacname = 0;
	}
	var my_radar_area = radarData[myacname][7];
	var my_radar_range = radarData[myacname][5];
	#return( my_radar_range / my_radar_area);
	#var my_plane = radarData[myacname][2];
	#print ("aircraft = " ~ my_plane);
	#print ("range = " ~ my_radar_range);
	#print ("aera = " ~ my_radar_area);
}



var radis = func(i, my_radarcorr) {
	# Get the multiplayer aircraft name.
	var mpnode_string = "ai/models/multiplayer[" ~ i ~ "]";
	var mpnode =  props.globals.getNode(mpnode_string);
	var mpname_node_string = mpnode_string ~ "/sim/model/path";
	var mpname_node = props.globals.getNode(mpname_node_string);

	if (mpname_node != nil) {
		var mpname = mpname_node.getValue();
		if (mpname != nil) {
			var splitname = split("/", mpname);
			#debug.dump(splitname);
			var cutname = splitname[1];
			#print (cutname);

			# Calculate the rcs detection range,
			# if aircraft is not found in list, 0 (generic) will be used.
			var acname = aircraftData[cutname];
			if (acname == nil) { acname = 0 }
			var rcs_4r = radarData[acname][3];
			var radartype = radarData[acname][1];

			# Add a correction factor for altitude, as lower alt means
			# shorter radar distance (due to air turbulence).
			var alt_corr = 1;
			var alt_ac = mpnode.getNode("position/altitude-ft").getValue();
			if (alt_ac <= 1000) {
				alt_corr = 0.6;
			} elsif ((alt_ac > 1000) and (alt_ac <= 5000)) {
				alt_corr = 0.8;
			}

			# Add a correction factor for altitude AGL.
			var agl_corr = 1;
			var mp_lon = mpnode.getNode("position/longitude-deg").getValue();
			var mp_lat = mpnode.getNode("position/latitude-deg").getValue();
			var mp_pos = geo.Coord.new().set_latlon(mp_lat, mp_lon);
			var pos_elev = geo.elevation(mp_pos.lat(), mp_pos.lon());
			var mp_agl = alt_ac - ( pos_elev / FT2M );
			if (mp_agl <= 20) {
				agl_corr = 0.03;
			} elsif ((mp_agl > 20) and (mp_agl <= 50)) {
				agl_corr = 0.08;
			} elsif ((mp_agl > 50) and (mp_agl <= 120)) {
				agl_corr = 0.8;
			}

			# Calculate the detection distance for this multiplayer.
			var det_range = my_radarcorr * rcs_4r * alt_corr * agl_corr / NM2KM;
			#print (radartype);
			#print (rcs_4r);

			### Compare if aircraft is in detection range and return.
			var act_range = mpnode.getNode("radar/range-nm").getValue();
			if ((act_range == nil) or (act_range == 0)) {
				act_range = 500;
			}
			#print (det_range ~ " " ~ act_range);
			if (det_range >= act_range) {
				#print("paint it");
				return(1);
			}
		}
	}
	return(0);
}

### convert aircraft to lookup number for table below:

aircraftData = {
"generic" : "0",
"707" : "1",
"737-300" : "2",
"747" : "3",
"787" : "4","777" : "4",
"A24-Viking" : "5",
"A-10" : "6",
"A300" : "7",
"A320" : "8",
"A380" : "9",
"a4" : "10",
"A-6E" : "11",
"A6M2" : "12",
"Albatross" : "13",
"Aerostar-700" : "14",
"Alouette-II" : "15",
"Alouette-III" : "16",
"Alphajet" : "17",
"an-2" : "18",
"AN-225" : "19",
"apache" : "20",
"ASK21" : "21","asw20" : "21","bocian" : "21",
"b1900d" : "22",
"B-1B" : "23",
"B-2" : "24",
"b29" : "25",
"B-52F" : "26",
"BAC-TSR2" : "27",
"beaufighter" : "28",
"bf109" : "29",
"Buccaneer" : "30",
"c310" : "31","c310u3a" : "31",
"c172" : "32","c172p" : "32","c172r" : "32",
"c182" : "32","c182rg" : "32",
"dhc6" : "33",
"E3B" : "34",
"F-86" : "35",
"f104" : "36",
"f-14b" : "37",
"f-14d" : "38",
"f15" : "39","f15c" : "39",
"f16" : "40",
"f18" : "41",
"f22" : "42",
"f35" : "43",
"f117" : "44",
"fokker50" : "45",
"harrier" : "46",
"hunter" : "47",
"j22" : "48",
"KC135" : "49",
"Lightning" : "50",
"SR71-Blackbird" : "51",
"MiG-21" : "52",
"Mig-29" : "53",
"mirage2000" : "54",
"MPCarrier" : "55",
"Tornado" : "56"
};

### radar lookup table , consisting aircraft name, RCS(m2), 4th root of RCS, radar type, max. radar range(km), max. radar range target seize(RCS)m2, 4th root of radar RCS

radarData = [
[0, "generic", 5, 1.49, "APG-63", 150, 100, 3.16],
[1, "707", 80, 2.34, "none", 0, 0, 0],#guess
[2, "737", 50, 2.11, "none", 0, 0, 0],#guess
[3, "747", 100, 2.34, "none", 0, 0, 0],#guess
[4, "787", 35, 1.86, "WXR-2100", 160, 100, 3.16],#guess
[5, "A24-Viking", 2, 1.19, "none", 0, 0, 0],#guess
[6, "A-10", 25, 2.23, "none", 0, 0, 0],
[7, "A300", 80, 2.23, "none", 0, 0, 0],#guess
[8, "A320", 50, 1.96, "none", 0, 0, 0],#guess
[9, "A380", 100, 2.11, "none", 0, 0, 0],#guess
[10, "a4", 10, 1.77, "APG-53", 15, 5, 1.49],
[11, "A-6E", 14, 1.93, "APQ-112", 150, 100, 3.16],
[12, "A6M2", 15, 1.96, "none", 0, 0, 0],#guess
[13, "Albatross", 40, 2.51, "none", 0, 0, 0],#guess
[14, "Aerostar-700", 10, 1.86, "none", 0, 0, 0],#guess
[15, "Alouette-II", 15, 2.51, "none", 0, 0, 0],#guess
[16, "Alouette-III", 20, 2.11, "none", 0, 0, 0],#guess
[17, "Alphajet", 5, 1.49, "none", 0, 0, 0],#guess
[18, "an-2", 2, 1.19, "none", 0, 0, 0],#guess
[19, "AN-225", 100, 2.59, "unknown", 0, 0, 0],#guess
[20, "apache", 30, 2.34, "APG-78", 8, 1, 1],#guess
[21, "ASK21", 1, 1, "none", 0, 0, 0],#guess
[22, "b1900d", 20, 2.11, "wx500", 60, 100, 3.16],#guess
[23, "B-1B", 4, 1.41, "APQ-164", 296, 100, 3.16],
[24, "B-2", 0.0015, 0.19, "APQ-181", 333, 100, 3.16],
[25, "b29", 100, 3.16, "APQ-19", 45, 100, 3.16],
[26, "B-52F", 100, 3.16, "APQ-166", 296, 100, 3.16],
[27, "BAC-TSR2", 15, 1.86, "Blue Parrot", 46, 100, 3.16],
[28, "beaufighter", 9, 1.73, "none", 0, 0, 0],
[29, "bf109", 15, 1.96, "none", 0, 0, 0],
[30, "Buccaneer", 10, 1.77, "Blue Parrot", 46, 100, 3.16],
[31, "c310", 4, 1.41, "none", 0, 0, 0],
[32, "c172", 2, 1.19, "none", 0, 0, 0],
[33, "dhc6", 5, 1.49, "none", 0, 0, 0],
[34, "E3B", 100, 2.23, "APY-1/2", 650, 100, 3.16],
[35, "F-86", 9, 1.73, "APG-37", 50, 100, 3.16],
[36, "f104", 9, 1.73, "ASG-14", 60, 100, 3.16],
[37, "f-14b", 25, 2.23, "AWG-9", 333, 100, 3.16],
[38, "f-14d", 25, 2.23, "APG-71", 380, 100, 3.16],
[39, "f-15", 30, 2.34, "APG-70", 235, 100, 3.16],
[40, "f16", 1.5, 1.11, "APG-68", 296, 100, 3.16],
[41, "f18", 1.0, 1.00, "APG-73", 326, 100, 3.16],
[42, "f22", 0.0010, 0.17, "APG-77", 410, 100, 3.16],
[43, "f35", 0.0025, 0.22, "APG-81", 350, 100, 3.16],
[44, "f117", 0.015, 0.35, "none", 0, 0, 0],
[45, "fokker50", 40, 1.96, "none", 0, 0, 0],
[46, "harrier", 15, 1.96, "APG-65", 296, 100, 3.16],
[47, "hunter", 8, 2, "Akco", 10, 100, 3.16],
[48, "j22", 9, 1.79, "none", 0, 0, 0],
[49, "KC135", 100, 2.43, "APN-218", 160, 100, 3.16],
[50, "Lightning", 5, 1.49, "AI-23", 111, 100, 3.16],
[51, "SR71", 0.015, 0.35, "APQ-108", 200, 100, 3.16],#range classified
[52, "MiG-21", 4, 1.41, "RP-21", 18, 100, 3.16],
[53, "Mig-29", 7, 1.63, "Sapfir", 115, 100, 3.16],
[54, "mirage2000", 2, 1.19, "RDY", 220, 100, 3.16],
[55, "MPCarrier", 10000, 10, "SPS-49", 525, 100, 3.16],
[56, "Tornado", 7, 1.63, "Foxhunter", 210, 100, 3.16]
];