adding telescope to hpc tranformation function

kis_tools/gris/util.py

@@ -24,6 +24,7 @@ from astropy.coordinates import SkyCoord, GCRS, get_sun
 from astropy.io.fits.hdu.hdulist import fitsopen as fitsopen
 from sunpy.coordinates import Helioprojective
 
+from kis_tools.util.calculations import rotate_around_origin
 from kis_tools.util.constants import gregor_coords
 from kis_tools.util.util import gris_run_number
 
@@ -211,3 +212,23 @@ def gregor_parallactic_angle(time, hpc_x=None, hpc_y=None):
     angle = gregor_observer.parallactic_angle(time, sun_coords)
     angle = angle.to('degree').value
     return angle
+
+
+def telescope_to_hpc(slitposx=None, slitposy=None, p0_angle=None, xcenter=None, ycenter=None):
+    """
+    Transform GRIS header coordinate data to HPC coordinates
+    Args:
+        slitposx: float SLITPOSX in arcsec
+        slitposy: float SLITPOSY in arcsec
+        p0_angle:  float p0_angle in degrees
+        xcenter: float X_center in arcsec (stored in GDBS upon centering the telescope)
+        ycenter: float Y_center in arcsec (stored in GDBS upon centering the telescope)
+
+    Returns:
+        hpc_x, hpc_y tuple of helioprojective coordinates in arcseconds
+
+    """
+    xi = slitposx - xcenter
+    yi = slitposy - ycenter
+    rotated = rotate_around_origin((xi, yi), np.radians(p0_angle))
+    return rotated