diff --git a/src/plugins/layers/useGrayLine.js b/src/plugins/layers/useGrayLine.js
index 51df3b5..6ba37c9 100644
--- a/src/plugins/layers/useGrayLine.js
+++ b/src/plugins/layers/useGrayLine.js
@@ -100,6 +100,39 @@ function calculateSolarAltitude(date, latitude, longitude) {
return altitude;
}
+// Split polyline at date line to avoid lines cutting across the map
+function splitAtDateLine(points) {
+ if (points.length < 2) return [points];
+
+ const segments = [];
+ let currentSegment = [points[0]];
+
+ for (let i = 1; i < points.length; i++) {
+ const prev = points[i - 1];
+ const curr = points[i];
+ const prevLon = prev[1];
+ const currLon = curr[1];
+ const lonDiff = Math.abs(currLon - prevLon);
+
+ // If longitude jumps more than 180°, we've crossed the date line
+ if (lonDiff > 180) {
+ // Finish current segment
+ segments.push(currentSegment);
+ // Start new segment
+ currentSegment = [curr];
+ } else {
+ currentSegment.push(curr);
+ }
+ }
+
+ // Add final segment
+ if (currentSegment.length > 0) {
+ segments.push(currentSegment);
+ }
+
+ return segments.filter(seg => seg.length >= 2);
+}
+
// Generate terminator line for a specific solar altitude
function generateTerminatorLine(date, solarAltitude = 0, numPoints = 360) {
const points = [];
@@ -113,64 +146,78 @@ function generateTerminatorLine(date, solarAltitude = 0, numPoints = 360) {
const hourAngle = calculateHourAngle(date, lon);
const haRad = hourAngle * Math.PI / 180;
- // Use the solar altitude equation to solve for latitude
- // sin(altitude) = sin(lat) * sin(dec) + cos(lat) * cos(dec) * cos(HA)
- // Rearranging: sin(altitude) - sin(lat) * sin(dec) = cos(lat) * cos(dec) * cos(HA)
-
- // For terminator (altitude = 0), the equation simplifies
- // We need to solve: tan(lat) = -tan(dec) / cos(HA)
-
const cosHA = Math.cos(haRad);
const sinDec = Math.sin(decRad);
const cosDec = Math.cos(decRad);
const sinAlt = Math.sin(altRad);
- // Solve using the quadratic formula or direct calculation
- // sin(lat) = (sin(alt) - cos(lat) * cos(dec) * cos(HA)) / sin(dec)
-
- // Better approach: use atan2 for proper terminator calculation
- // The terminator latitude for a given longitude is:
- // lat = atan(-cos(HA) / tan(dec)) when dec != 0
-
let lat;
+ // Check if solution exists (sun can reach this altitude at this longitude)
+ // For terminator and twilight, check if |cos(HA) * cos(dec)| <= 1 - sin(alt) * sin(dec)
+ const testValue = (sinAlt - sinDec * sinDec) / (cosDec * cosDec * cosHA * cosHA);
+
if (Math.abs(declination) < 0.01) {
// Near equinox: terminator is nearly straight along equator
lat = 0;
+ } else if (Math.abs(cosDec) < 0.001) {
+ // Near solstice: sun is directly over tropic, skip this point
+ continue;
} else {
// Standard case: calculate terminator latitude
- // Formula: cos(lat) * cos(dec) * cos(HA) = -sin(lat) * sin(dec) (for altitude = 0)
- // This gives: tan(lat) = -cos(HA) / tan(dec)
-
const tanDec = Math.tan(decRad);
- if (Math.abs(tanDec) < 0.0001) {
- lat = 0;
- } else {
- lat = Math.atan(-cosHA / tanDec) * 180 / Math.PI;
- }
- // For twilight (altitude < 0), we need to adjust
- if (solarAltitude !== 0) {
- // Use iterative solution for twilight calculations
- // cos(lat) * cos(dec) * cos(HA) + sin(lat) * sin(dec) = sin(alt)
+ if (solarAltitude === 0) {
+ // Terminator (sunrise/sunset line)
+ // Formula: tan(lat) = -cos(HA) / tan(dec)
+ if (Math.abs(tanDec) > 0.0001) {
+ lat = Math.atan(-cosHA / tanDec) * 180 / Math.PI;
+ } else {
+ lat = 0;
+ }
+ } else {
+ // Twilight zones (negative solar altitude)
+ // Use Newton-Raphson iteration to solve for latitude
+ // Equation: sin(lat) * sin(dec) + cos(lat) * cos(dec) * cos(HA) = sin(alt)
- // Newton-Raphson iteration to solve for latitude
- let testLat = lat * Math.PI / 180;
- for (let iter = 0; iter < 5; iter++) {
+ // Initial guess based on terminator
+ let testLat = Math.atan(-cosHA / tanDec);
+
+ // Iterate to find solution
+ let converged = false;
+ for (let iter = 0; iter < 10; iter++) {
const f = Math.sin(testLat) * sinDec + Math.cos(testLat) * cosDec * cosHA - sinAlt;
const fPrime = Math.cos(testLat) * sinDec - Math.sin(testLat) * cosDec * cosHA;
+
+ if (Math.abs(f) < 0.0001) {
+ converged = true;
+ break;
+ }
+
if (Math.abs(fPrime) > 0.0001) {
testLat = testLat - f / fPrime;
+ } else {
+ break;
}
+
+ // Constrain to valid latitude range during iteration
+ testLat = Math.max(-Math.PI/2, Math.min(Math.PI/2, testLat));
+ }
+
+ // Only use the point if iteration converged
+ if (!converged) {
+ continue;
}
+
lat = testLat * 180 / Math.PI;
}
}
- // Clamp latitude to valid range
- lat = Math.max(-90, Math.min(90, lat));
+ // Strict clamping to valid latitude range
+ lat = Math.max(-85, Math.min(85, lat));
- if (isFinite(lat) && isFinite(lon)) {
+ // Only add point if it's valid and not at extreme latitude
+ if (isFinite(lat) && isFinite(lon) && Math.abs(lat) < 85) {
points.push([lat, lon]);
}
}
@@ -488,104 +535,123 @@ export function useLayer({ enabled = false, opacity = 0.5, map = null }) {
// Main terminator (solar altitude = 0°)
const terminator = generateTerminatorLine(currentTime, 0, 360);
- const terminatorLine = L.polyline(terminator, {
- color: '#ff6600',
- weight: 3,
- opacity: opacity * 0.8,
- dashArray: '10, 5'
+ const terminatorSegments = splitAtDateLine(terminator);
+
+ terminatorSegments.forEach(segment => {
+ const terminatorLine = L.polyline(segment, {
+ color: '#ff6600',
+ weight: 3,
+ opacity: opacity * 0.8,
+ dashArray: '10, 5'
+ });
+ terminatorLine.bindPopup(`
+
+ 🌅 Solar Terminator
+ Sun altitude: 0°
+ Enhanced HF propagation zone
+ UTC: ${currentTime.toUTCString()}
+
+ `);
+ terminatorLine.addTo(map);
+ newLayers.push(terminatorLine);
});
- terminatorLine.bindPopup(`
-
- 🌅 Solar Terminator
- Sun altitude: 0°
- Enhanced HF propagation zone
- UTC: ${currentTime.toUTCString()}
-
- `);
- terminatorLine.addTo(map);
- newLayers.push(terminatorLine);
// Enhanced DX zone (±5° from terminator)
if (showEnhancedZone) {
const enhancedUpper = generateTerminatorLine(currentTime, 5, 360);
const enhancedLower = generateTerminatorLine(currentTime, -5, 360);
- // Create polygon for enhanced zone
- const enhancedZone = [...enhancedUpper, ...enhancedLower.reverse()];
- const enhancedPoly = L.polygon(enhancedZone, {
- color: '#ffaa00',
- fillColor: '#ffaa00',
- fillOpacity: opacity * 0.15,
- weight: 1,
- opacity: opacity * 0.3
- });
- enhancedPoly.bindPopup(`
-
- ⭐ Enhanced DX Zone
- Best HF propagation window
- ±5° from terminator
- Ideal for long-distance contacts
-
- `);
- enhancedPoly.addTo(map);
- newLayers.push(enhancedPoly);
+ // Only create polygon if we have valid points
+ if (enhancedUpper.length > 2 && enhancedLower.length > 2) {
+ // Create polygon for enhanced zone
+ const enhancedZone = [...enhancedUpper, ...enhancedLower.reverse()];
+ const enhancedPoly = L.polygon(enhancedZone, {
+ color: '#ffaa00',
+ fillColor: '#ffaa00',
+ fillOpacity: opacity * 0.15,
+ weight: 1,
+ opacity: opacity * 0.3
+ });
+ enhancedPoly.bindPopup(`
+
+ ⭐ Enhanced DX Zone
+ Best HF propagation window
+ ±5° from terminator
+ Ideal for long-distance contacts
+
+ `);
+ enhancedPoly.addTo(map);
+ newLayers.push(enhancedPoly);
+ }
}
// Twilight zones
if (showTwilight) {
// Civil twilight (sun altitude -6°)
const civilTwilight = generateTerminatorLine(currentTime, -6, 360);
- const civilLine = L.polyline(civilTwilight, {
- color: '#4488ff',
- weight: 2,
- opacity: twilightOpacity * 0.6,
- dashArray: '5, 5'
+ const civilSegments = splitAtDateLine(civilTwilight);
+
+ civilSegments.forEach(segment => {
+ const civilLine = L.polyline(segment, {
+ color: '#4488ff',
+ weight: 2,
+ opacity: twilightOpacity * 0.6,
+ dashArray: '5, 5'
+ });
+ civilLine.bindPopup(`
+
+ 🌆 Civil Twilight
+ Sun altitude: -6°
+ Good propagation conditions
+
+ `);
+ civilLine.addTo(map);
+ newLayers.push(civilLine);
});
- civilLine.bindPopup(`
-
- 🌆 Civil Twilight
- Sun altitude: -6°
- Good propagation conditions
-
- `);
- civilLine.addTo(map);
- newLayers.push(civilLine);
// Nautical twilight (sun altitude -12°)
const nauticalTwilight = generateTerminatorLine(currentTime, -12, 360);
- const nauticalLine = L.polyline(nauticalTwilight, {
- color: '#6666ff',
- weight: 1.5,
- opacity: twilightOpacity * 0.4,
- dashArray: '3, 3'
+ const nauticalSegments = splitAtDateLine(nauticalTwilight);
+
+ nauticalSegments.forEach(segment => {
+ const nauticalLine = L.polyline(segment, {
+ color: '#6666ff',
+ weight: 1.5,
+ opacity: twilightOpacity * 0.4,
+ dashArray: '3, 3'
+ });
+ nauticalLine.bindPopup(`
+
+ 🌃 Nautical Twilight
+ Sun altitude: -12°
+ Moderate propagation
+
+ `);
+ nauticalLine.addTo(map);
+ newLayers.push(nauticalLine);
});
- nauticalLine.bindPopup(`
-
- 🌃 Nautical Twilight
- Sun altitude: -12°
- Moderate propagation
-
- `);
- nauticalLine.addTo(map);
- newLayers.push(nauticalLine);
// Astronomical twilight (sun altitude -18°)
const astroTwilight = generateTerminatorLine(currentTime, -18, 360);
- const astroLine = L.polyline(astroTwilight, {
- color: '#8888ff',
- weight: 1,
- opacity: twilightOpacity * 0.3,
- dashArray: '2, 2'
+ const astroSegments = splitAtDateLine(astroTwilight);
+
+ astroSegments.forEach(segment => {
+ const astroLine = L.polyline(segment, {
+ color: '#8888ff',
+ weight: 1,
+ opacity: twilightOpacity * 0.3,
+ dashArray: '2, 2'
+ });
+ astroLine.bindPopup(`
+
+ 🌌 Astronomical Twilight
+ Sun altitude: -18°
+ Transition to night propagation
+
+ `);
+ astroLine.addTo(map);
+ newLayers.push(astroLine);
});
- astroLine.bindPopup(`
-
- 🌌 Astronomical Twilight
- Sun altitude: -18°
- Transition to night propagation
-
- `);
- astroLine.addTo(map);
- newLayers.push(astroLine);
}
setLayers(newLayers);