//------------------------------------------------------------------------------
// Moves our reference lat lon based on the distance moved.
//------------------------------------------------------------------------------
void MapPage::moveMap(const int startX, const int startY, const int endX, const int endY)
{
double eLat = 0, eLon = 0, lat = 0, lon = 0, sLat = 0, sLon = 0, deltaLat = 0, deltaLon = 0;
// figure our lat/lon positioning
pixelsToLatLon(startX, startY, sLat, sLon);
pixelsToLatLon(endX, endY, eLat, eLon);
// get our delta movement
deltaLat = sLat - eLat;
deltaLon = sLon - eLon;
lat = getReferenceLatDeg();
lon = getReferenceLonDeg();
lat += deltaLat;
lon += deltaLon;
// As the world turns.... we need to flip the maps!
if (lon > 180) lon = -180;
else if (lon < -180) lon = 180;
if (lat > 90) lat = -90;
else if (lat < -90) lat = 90;
setReferenceLatDeg(lat);
setReferenceLonDeg(lon);
}
void Display::mouseMotionEvent(const int x, const int y)
{
if (dragging) {
const auto page = static_cast<MapPage*>(subpage());
if (page != nullptr) {
// get our ref lat, because we won't go passed 70 degrees lat (either way);
const double lat = page->getReferenceLatDeg();
if (lat < 70 && lat > -70) {
page->moveMap(startX, startY, x, y);
} else {
if (lat > 0) page->setReferenceLatDeg(65);
else page->setReferenceLatDeg(-65);
}
startX = x;
startY = y;
}
}
setMouse(x, y);
}
//------------------------------------------------------------------------------
// converts screen to lat/lon coordinates
//------------------------------------------------------------------------------
bool MapPage::screen2LatLon(const LCreal x, const LCreal y,
double* const lat, double* const lon) const
{
bool ok = false;
const double scale = getScale();
const double cosLat = getCosRefLat();
if (lat != nullptr && lon != nullptr && scale != 0 && cosLat != 0) {
// buffer the inputs
double screenX = x;
double screenY = y;
// Adjust for the decentered displayment
if ( !getCentered() ) screenY -= getDisplacement();
// Scale from screen (inches) to A/C (NM) and
// transpose the X and Y from screen to A/C
const double acX = screenY/scale;
const double acY = screenX/scale;
// Rotate A/C to NED
double earthX = 0.0;
double earthY = 0.0;
if (getNorthUp()) {
earthX = acX;
earthY = acY;
}
else {
earthX = (acX * headingCos) - (acY * headingSin);
earthY = (acX * headingSin) + (acY * headingCos);
}
// Convert nautical miles (NED) from ref point to lat/lon
*lat = (earthX/60.0) + getReferenceLatDeg();
*lon = (earthY/(60.0*cosLat)) + getReferenceLonDeg();
ok = true;
}
return ok;
}
//------------------------------------------------------------------------------
// converts lat/lon to screen coordinates
//------------------------------------------------------------------------------
bool MapPage::latLon2Screen(const double lat, const double lon,
LCreal* const x, LCreal* const y) const
{
bool ok = false;
if (x != nullptr && y != nullptr) {
// Convert to nautical miles (NED) centered on ownship
const double earthX = ((lat - getReferenceLatDeg()) * 60.0);
const double earthY = ((lon - getReferenceLonDeg()) * 60.0 * getCosRefLat());
// Rotate to aircraft coordinates
double acX = 0;
double acY = 0;
if (getNorthUp()) {
acX = earthX;
acY = earthY;
}
else {
acX = (earthX * headingCos) + (earthY * headingSin);
acY = -(earthX * headingSin) + (earthY * headingCos);
}
// Scale from nautical miles to inches and
// transpose the X and Y from A/C to screen
double screenY = acX * getScale();
const double screenX = acY * getScale();
// Adjust for the decentered displayment
if ( !getCentered() ) screenY += getDisplacement();
*x = static_cast<LCreal>(screenX);
*y = static_cast<LCreal>(screenY);
ok = true;
}
return ok;
}
