/*
* Convert from one equinox (or named coordinate system) to another.
* The first 2 parameters may be numbers, such as "2000" or "1950", or
* coordinate system names, like "J2000", "FK5", "GALACTIC", "ECLIPTIC", ...
* Epoch is the besselian epoch in years.
* If dflag is 1, the ra value was converted to hours by dividing by 15
*/
int WorldCoords::convertEquinox(const char* fromEquinoxStr, const char* toEquinoxStr, double epoch, int dflag)
{
// check for numerical equinox
double from_equinox = 0.;
double to_equinox = 0.;
if (getEquinox(fromEquinoxStr, from_equinox) == 0 && getEquinox(toEquinoxStr, to_equinox) == 0)
return convertEquinox(from_equinox, to_equinox);
// convert from one system to another
int sys1 = wcscsys((char*)fromEquinoxStr);
if (sys1 == -1)
return error("bad equinox value: ", fromEquinoxStr);
int sys2 = wcscsys((char*)toEquinoxStr);
if (sys2 == -1)
return error("bad equinox value: ", toEquinoxStr);
double dtheta = ra_.val();
if (dflag)
dtheta *= 15; // hours to degrees
double dphi = dec_.val();
wcscon(sys1, sys2, from_equinox, to_equinox, &dtheta, &dphi, epoch);
if (sys2 == WCS_J2000 || sys2 == WCS_B1950)
dtheta /= 15; // degrees to hours
ra_ = HMS(dtheta);
dec_ = HMS(dphi);
dec_.show_sign(1);
return 0;
}
double* PPWcsImage::pix2sky(QPointF pos)
{
if (!wcs)
return world;
// Get unbinned pixel
float xf, yf;
xf = M*(pos.x()-1)+2-0.5;
yf = (M*(pos.y()-1))-0.5;
pix2wcs(wcs, xf, yf, &world[0], &world[1]);
// Check if coordinates are galatic
if (wcs->syswcs != WCS_J2000)
wcscon(wcs->syswcs, WCS_J2000, wcs->equinox, wcs->eqout, &world[0], &world[1], wcs->epoch);
// Perhaps the transformationStatus needs to be checked ...
return world;
}
