Issue #39: Wrong Earth rotation measure in tod_to_itrs() (changelog update)

Author: attipaci

CHANGELOG.md

@@ -14,12 +14,23 @@ available on the `main` branch.
 
 ### Fixed
 
+ - `tod_to_itrs()` used wrong Earth rotation measure (`NOVAS_ERA` instead of `NOVAS_GST`).
+
  - `gcrs_to_j2000` transformed in the wrong direction.
 
  - `gcrs_to_cirs()` did not handle well if input and output vectors were the same.
 
  - `tt2tdb()` Had a wrong scaling in sinusoidal period, resulting in an error of up to +/- 1.7 ms.
 
+ - Fix portability to non-Intel x86 platforms (see Issue #29). Previously, SuperNOVAS used `char` for storing integer 
+   coefficients, assuming `char` was a signed. However, on some platforms like ARM and PowerPC `char` is unsigned, 
+   which broke many calculations badly for such platforms. As of now, we use the explicit platform-independent 
+   `int8_t` storage type for these coefficients.
+
+ - Division by zero bug in `d_light()` (since NOVAS C 3.1) if the first position argument is the ephemeris reference
+   position (e.g. the Sun for `solsys3.c`). The bug affects for example `grav_def()`, where it effectively results in
+   the gravitational deflection due to the Sun being skipped. See Issue #28.
+   
  - Radial velocity calculation to precede aberration and gravitational bending in `place()`, since the radial velocity 
    that is observed is in the geometric direction towards the source (unaffected by aberration). A proper accounting 
    for the gravitational bending around some intermediate mass would require calculating the direction of light that 

src/novas.c

@@ -3021,7 +3021,7 @@ int cirs_to_itrs(double jd_tt_high, double jd_tt_low, double ut1_to_tt, enum nov
  */
 int tod_to_itrs(double jd_tt_high, double jd_tt_low, double ut1_to_tt, enum novas_accuracy accuracy, double xp,
         double yp, const double *in, double *out) {
-  prop_error("tod_to_itrs", cel2ter(jd_tt_high, jd_tt_low - ut1_to_tt / DAY, ut1_to_tt, EROT_ERA, accuracy, NOVAS_DYNAMICAL_CLASS, xp, yp, in,
+  prop_error("tod_to_itrs", cel2ter(jd_tt_high, jd_tt_low - ut1_to_tt / DAY, ut1_to_tt, EROT_GST, accuracy, NOVAS_DYNAMICAL_CLASS, xp, yp, in,
           out), 0);
   return 0;
 }