void Ecliptic::drawCompassLabels() {
const Projector* proj = SkyMap::Instance()->projector();
KStarsData* data = KStarsData::Instance();
SkyLabeler* skyLabeler = SkyLabeler::Instance();
// Set proper color for labels
QColor color( data->colorScheme()->colorNamed( "CompassColor" ) );
skyLabeler->setPen( QPen( QBrush(color), 1, Qt::SolidLine) );
KSNumbers num( data->ut().djd() );
dms elat(0.0), elng(0.0);
QString label;
for( int ra = 0; ra < 23; ra += 6 ) {
elng.setH( ra );
SkyPoint o;
o.setFromEcliptic( num.obliquity(), elng, elat );
o.setRA0( o.ra() );
o.setDec0( o.dec() );
o.EquatorialToHorizontal( data->lst(), data->geo()->lat() );
bool visible;
QPointF cpoint = proj->toScreen( &o, false, &visible );
if( visible && proj->checkVisibility( &o ) ) {
label.setNum( o.ra().reduce().Degrees() );
skyLabeler->drawGuideLabel( cpoint, label, 0.0 );
}
}
}
Ecliptic::Ecliptic(SkyComposite *parent ) :
LineListIndex( parent, i18n("Ecliptic") ),
m_label( name() )
{
KStarsData *data = KStarsData::Instance();
KSNumbers num( data->ut().djd() );
dms elat(0.0), elng(0.0);
const double eps = 0.1;
const double minRa = 0.0;
const double maxRa = 23.0;
const double dRa = 2.0;
const double dRa2 = 2. / 5.;
for(double ra = minRa; ra < maxRa; ra += dRa ) {
LineList* lineList = new LineList();
for(double ra2 = ra; ra2 <= ra + dRa + eps; ra2 += dRa2 ) {
elng.setH( ra2 );
SkyPoint* o = new SkyPoint();
o->setFromEcliptic( num.obliquity(), elng, elat );
o->setRA0( o->ra().Hours() );
o->setDec0( o->dec().Degrees() );
o->EquatorialToHorizontal( data->lst(), data->geo()->lat() );
lineList->append( o );
}
appendLine( lineList );
}
}
void KSPlanetBase::findPA( const KSNumbers *num ) {
//Determine position angle of planet (assuming that it is aligned with
//the Ecliptic, which is only roughly correct).
//Displace a point along +Ecliptic Latitude by 1 degree
SkyPoint test;
dms newELat( ecLat().Degrees() + 1.0 );
test.setFromEcliptic( num->obliquity(), ecLong(), newELat );
double dx = ra().Degrees() - test.ra().Degrees();
double dy = test.dec().Degrees() - dec().Degrees();
double pa;
if ( dy ) {
pa = atan2( dx, dy )*180.0/dms::PI;
} else {
pa = dx < 0 ? 90.0 : -90.0;
}
setPA( pa );
}