Store the STF unit system in the engine. Scale the internal energies of the...

Store the STF unit system in the engine. Scale the internal energies of the particles to the STF unit system.

src/engine.h

@@ -191,6 +191,9 @@ struct engine {
 
   /* The internal system of units */
   const struct unit_system *internal_units;
+  
+  /* The STF system of units */
+  struct unit_system *stf_units;
 
   /* Snapshot information */
   double timeFirstSnapshot;

src/velociraptor_interface.c

@@ -48,12 +48,11 @@ void velociraptor_init(struct engine *e) {
     struct unitinfo unit_info;
     struct siminfo sim_info;
     
-    struct unit_system vel_us;
     struct phys_const vel_const;
 
     /* Initialize velociraptor unit system and constants */
-    units_init(&vel_us, e->parameter_file, "VelociraptorUnitSystem");
-    phys_const_init(&vel_us, e->parameter_file, &vel_const);
+    units_init(e->stf_units, e->parameter_file, "VelociraptorUnitSystem");
+    phys_const_init(e->stf_units, e->parameter_file, &vel_const);
 
     /* Set cosmological constants. */
     cosmo_info.atime = e->cosmology->a;
@@ -73,10 +72,10 @@ void velociraptor_init(struct engine *e) {
     message("w_de: %e", cosmo_info.w_de);
 
     /* Set unit conversions. */
-    unit_info.lengthtokpc = units_conversion_factor(e->internal_units, &vel_us, UNIT_CONV_LENGTH); /* 1kpc <=> 3.086e21cm */
-    unit_info.velocitytokms = units_conversion_factor(e->internal_units, &vel_us, UNIT_CONV_SPEED); /* 1km/s <=> 1e5cm/s */
-    unit_info.masstosolarmass = units_conversion_factor(e->internal_units, &vel_us, UNIT_CONV_MASS); /* 1M_sol <=> 1.99e33g */
-    unit_info.energyperunitmass = units_conversion_factor(e->internal_units, &vel_us, UNIT_CONV_ENERGY_PER_UNIT_MASS); /* Conversion for gravitational potential. */
+    unit_info.lengthtokpc = units_conversion_factor(e->internal_units, e->stf_units, UNIT_CONV_LENGTH); /* 1kpc <=> 3.086e21cm */
+    unit_info.velocitytokms = units_conversion_factor(e->internal_units, e->stf_units, UNIT_CONV_SPEED); /* 1km/s <=> 1e5cm/s */
+    unit_info.masstosolarmass = units_conversion_factor(e->internal_units, e->stf_units, UNIT_CONV_MASS); /* 1M_sol <=> 1.99e33g */
+    unit_info.energyperunitmass = units_conversion_factor(e->internal_units, e->stf_units, UNIT_CONV_ENERGY_PER_UNIT_MASS); /* Conversion for gravitational potential. */
     unit_info.gravity = vel_const.const_newton_G; /* TODO: G = 6.67408e-8 (cgs) */
     unit_info.hubbleunit = e->cosmology->H; /* TODO: double check this. */
 
@@ -185,7 +184,8 @@ void velociraptor_invoke(struct engine *e) {
                        nr_hydro_parts * sizeof(float)) != 0)
         error("Failed to allocate array of internal energies for VELOCIraptor.");
     
-    for(int i=0; i<nr_hydro_parts; i++) internal_energies[i] = hydro_get_physical_internal_energy(&parts[i], e->cosmology);    
+    const float energy_scale = units_conversion_factor(e->internal_units, e->stf_units, UNIT_CONV_ENERGY); /* Conversion for particle internal energy. */
+    for(int i=0; i<nr_hydro_parts; i++) internal_energies[i] = hydro_get_physical_internal_energy(&parts[i], e->cosmology) * energy_scale;    
 
     message("MPI rank %d sending %lld gparts to VELOCIraptor.", e->nodeID, nr_gparts);