Pan plugin shows bad compass for galactic and ecliptic coordinates

[ejeschke]

When selecting "galactic" or "ecliptic" from the "WCS Coords" preferences, the compass does not adjust accordingly (as, for example, in ds9). This is because the endpoints of the arms are being calculated from a straight WCS conversion using the normal header of the image. So if the image header is RA---TAN, DEC--TAN type projection the arms will follow these in straight RA and DEC.

I suppose the idea would be to create a galactic or ecliptic projection and use that header to orient the arms.