function GetSurroundingGridIDs($sectional, $gridNum, $quadrant = "E", $format = "dmm")
{
$CenterGridCoords = grid2lonlat($sectional, $gridNum, $quadrant, "raw");
$CenterGrid = array("sectional" => $sectional, "grid" => $gridNum, "quadrant" => $quadrant);
$NorthGridLat = $CenterGridCoords['NE']['lat'] + 0.05;
$NorthGridLon = ($CenterGridCoords['NE']['lon'] + $CenterGridCoords['NW']['lon']) / 2;
$NorthGrid = lonlat2grid($NorthGridLon, $NorthGridLat);
$SouthGridLat = $CenterGridCoords['SE']['lat'] - 0.05;
$SouthGridLon = $NorthGridLon;
$SouthGrid = lonlat2grid($SouthGridLon, $SouthGridLat);
$EastGridLat = ($CenterGridCoords['NE']['lat'] + $CenterGridCoords['SE']['lat']) / 2;
$EastGridLon = $CenterGridCoords['NE']['lon'] + 0.05;
$EastGrid = lonlat2grid($EastGridLon, $EastGridLat);
$WestGridLat = $EastGridLat;
$WestGridLon = $CenterGridCoords['NW']['lon'] - 0.05;
$WestGrid = lonlat2grid($WestGridLon, $WestGridLat);
if ($CenterGrid['quadrant'] == "E") {
$NorthGrid['quadrant'] = "";
$SouthGrid['quadrant'] = "";
$EastGrid['quadrant'] = "";
$WestGrid['quadrant'] = "";
} else {
$NorthGrid['quadrant'] = " - " . $NorthGrid['quadrant'];
$SouthGrid['quadrant'] = " - " . $SouthGrid['quadrant'];
$EastGrid['quadrant'] = " - " . $EastGrid['quadrant'];
$WestGrid['quadrant'] = " - " . $WestGrid['quadrant'];
}
$SurroundingGrids = array("Center" => $CenterGrid, "North" => $NorthGrid, "South" => $SouthGrid, "East" => $EastGrid, "West" => $WestGrid);
return $SurroundingGrids;
}
$myquadrant = $_GET['myquadrant'];
}
if (isset($_GET['lon'])) {
$pointLongitude = $_GET['lon'];
$lonlatflag = 1;
}
if (isset($_GET['lat'])) {
$pointLatitude = $_GET['lat'];
}
if ($myquadrant != "E") {
$quadrantDisplay = "-" . $myquadrant;
}
# Determine the raw lon/lat of the top-left grid corner
$gridLon = $gridLat = $longitude = $latitude = 0;
if ($lonlatflag) {
$result1 = lonlat2grid($pointLongitude, $pointLatitude);
$sectional = $result1['sectional'];
$mygrid = $result1['grid'];
$myquadrant = $result1['quadrant'];
}
$result = grid2lonlat($sectional, $mygrid, $myquadrant, "raw");
$abbrev = $coordinates[$sectional]['Abbrev'];
$gridLon = $result['NW']['lon'];
$gridLat = $result['NW']['lat'];
$gridLabel = "{$abbrev} - {$mygrid}";
$filenameHeader = "Content-Disposition: attachment; filename=\"" . $abbrev . "_" . $mygrid . "-" . $myquadrant . ".kml\"";
$sectionalName = ucwords(strtolower(preg_replace("/_/", " ", $sectional)));
#echo "Lon: $gridLon Lat: $gridLat $abbrev - $mygrid \n";
?>
<!doctype html>
<html lang="en">
$output = $onload = "";
$rawLat = $rawLon = 0;
if ($submit == "Go") {
$output = "<div align=\"center\" class=\"coord\"><b>Not Found</b></div>";
$onload = "";
switch ($selectedFormat) {
case "dmm":
$rawLat = $latDegDMM + $latMinDMM / 60;
$rawLon = -($lonDegDMM + $lonMinDMM / 60);
break;
case "dms":
$rawLat = $latDegDMS + $latMinDMS / 60 + $latSecDMS / 3600;
$rawLon = -($lonDegDMS + $lonMinDMS / 60 + $lonSecDMS / 3600);
break;
}
$result = lonlat2grid($rawLon, $rawLat);
if (isset($result['quadrant'])) {
$quadrant = $result['quadrant'];
} else {
$quadrant = -1;
}
if ($quadrant > -1) {
$sectional = $result['sectional'];
$abbrev = $coordinates[$sectional]['Abbrev'];
$displaySectional = ucwords(strtolower(preg_replace("/_/", " ", $sectional)));
$grid = $result['grid'];
$quadrant = $result['quadrant'];
$output = "<div align=\"center\" class=\"coord\"><b>{$displaySectional} ({$abbrev}) {$grid} - {$quadrant}</b></div>";
$urlSrc = "id=" . $sectional . "&mygrid=" . $grid . "&myquadrant=" . $quadrant . "&myformat=" . $selectedFormat;
$onload = "onLoad=\"javascript:parent.setCornerUrl('" . $urlSrc . "');\"";
}
