(1) Made OpenMC load plots.xml upon initialization even if not in the plot runmode; (2) Made the finalize method clear plotting data; (3) allowed the openmc.lib and openmc.model package to call plot_geometry now that plots.xml would have been loaded

include/openmc/plot.h

@@ -30,9 +30,7 @@ namespace model {
 extern std::unordered_map<int, int> plot_map; //!< map of plot ids to index
 extern vector<Plot> plots;                    //!< Plot instance container
 
-extern uint64_t
-  plotter_prn_seeds[N_STREAMS]; // Random number seeds used for plotter
-extern int plotter_stream;      // Stream index used by the plotter
+extern uint64_t plotter_seed;      // Stream index used by the plotter
 
 } // namespace model
 
@@ -274,6 +272,9 @@ void voxel_finalize(hid_t dspace, hid_t dset, hid_t memspace);
 //! Read plot specifications from a plots.xml file
 void read_plots_xml();
 
+//! Clear memory
+void free_memory_plot();
+
 //! Create a ppm image for a plot object
 //! \param[in] plot object
 void create_ppm(Plot const& pl);

openmc/model/model.py

@@ -664,18 +664,12 @@ class Model:
                              "before executing this method!")
 
         with _change_directory(Path(cwd)):
-            # TODO: openmc.is_initialized doesnt read plots.xml unless it is
-            # in plot mode so the following will not work. Commented out for
-            # now and replacing with non-C API code
-            self.export_to_xml()
-            openmc.plot_geometry(output=output, openmc_exec=openmc_exec)
-
-            # if self.is_initialized:
-            #     # Compute the volumes
-            #     openmc.lib.plot_geometry(output)
-            # else:
-            #     self.export_to_xml()
-            #     openmc.plot_geometry(output=output, openmc_exec=openmc_exec)
+            if self.is_initialized:
+                # Compute the volumes
+                openmc.lib.plot_geometry(output)
+            else:
+                self.export_to_xml()
+                openmc.plot_geometry(output=output, openmc_exec=openmc_exec)
 
             if convert:
                 for p in self.plots:

src/finalize.cpp

@@ -15,6 +15,7 @@
 #include "openmc/message_passing.h"
 #include "openmc/nuclide.h"
 #include "openmc/photon.h"
+#include "openmc/plot.h"
 #include "openmc/random_lcg.h"
 #include "openmc/settings.h"
 #include "openmc/simulation.h"
@@ -45,6 +46,7 @@ void free_memory()
   free_memory_mesh();
   free_memory_tally();
   free_memory_bank();
+  free_memory_plot();
   if (mpi::master) {
     free_memory_cmfd();
   }
@@ -128,6 +130,7 @@ int openmc_finalize()
   data::temperature_min = 0.0;
   data::temperature_max = INFTY;
   model::root_universe = -1;
+  model::plotter_seed = 1;
   openmc::openmc_set_seed(DEFAULT_SEED);
 
   // Deallocate arrays

src/initialize.cpp

@@ -305,9 +305,11 @@ void read_input_xml()
   // Initialize distribcell_filters
   prepare_distribcell();
 
+  // Read the plots.xml regardless of plot mode in case plots are requested
+  // via the API
+  read_plots_xml();
   if (settings::run_mode == RunMode::PLOTTING) {
     // Read plots.xml if it exists
-    read_plots_xml();
     if (mpi::master && settings::verbosity >= 5)
       print_plot();
 

src/plot.cpp

@@ -119,9 +119,11 @@ extern "C" int openmc_plot_geometry()
 
 void read_plots_xml()
 {
-  // Check if plots.xml exists
+  // Check if plots.xml exists; this is only necessary when the plot runmode is
+  // initiated. Otherwise, we want to read plots.xml because it may be called
+  // later via the API. In that case, its ok for a plots.xml to not exist
   std::string filename = settings::path_input + "plots.xml";
-  if (!file_exists(filename)) {
+  if (!file_exists(filename) && settings::run_mode == RunMode::PLOTTING) {
     fatal_error(fmt::format("Plots XML file '{}' does not exist!", filename));
   }
 
@@ -138,6 +140,12 @@ void read_plots_xml()
   }
 }
 
+void free_memory_plot()
+{
+  model::plots.clear();
+  model::plot_map.clear();
+}
+
 //==============================================================================
 // CREATE_PPM creates an image based on user input from a plots.xml <plot>
 // specification in the portable pixmap format (PPM)