Merge pull request #1156 from LLNL/bugfix/whitlock/partition_material…

…_map

Make partitioner better about outputting material_map node.

CHANGELOG.md

@@ -15,6 +15,7 @@ and this project aspires to adhere to [Semantic Versioning](https://semver.org/s
 
 #### Blueprint
 - The `conduit::blueprint::mesh::partition()` function no longer issues an error when it receives a "maxshare" adjset.
+- The partitioner is better about outputting a "material_map" node for matsets. The "material_map" node is optional for some varieties of matset but they can also help the `conduit::blueprint::mesh::matset::to_silo()` function generate the right material numbers when a domain does not contain all materials.
 
 ## [0.8.8] - Released 2023-05-18
 

src/libs/blueprint/conduit_blueprint_mesh_partition.cpp

@@ -9337,6 +9337,16 @@ combine(const std::vector<Node> &inputs,
         out_matset["volume_fractions"][name].set(volume_fractions);
         out_matset["element_ids"][name].set(element_ids);
     }
+
+    // If the material_map does not exist, add it since it supplies the entire
+    // list of materials, which can be important when a domain does not have
+    // all materials.
+    if(!out_matset.has_child("material_map") && !material_map.empty())
+    {
+        Node &mm = out_matset["material_map"];
+        for(auto it = material_map.begin(); it != material_map.end(); it++)
+            mm[it->second] = it->first;
+    }
 }
 
 }

src/tests/blueprint/baselines/t_blueprint_mesh_partition/venn_uni_by_element_combined.yaml

@@ -24,6 +24,11 @@ matsets:
       circle_a: [9, 13, 10, 14]
       circle_b: [10, 11, 14, 15]
       circle_c: [5, 9, 6, 7, 10, 11]
+    material_map: 
+      background: 0
+      circle_a: 1
+      circle_b: 2
+      circle_c: 3
 fields: 
   original_vertex_ids: 
     topology: "topo"

src/tests/blueprint/baselines/t_blueprint_mesh_partition/venn_uni_by_material_combined.yaml

@@ -24,6 +24,11 @@ matsets:
       circle_a: [9, 13, 10, 14]
       circle_b: [10, 11, 14, 15]
       circle_c: [5, 9, 6, 7, 10, 11]
+    material_map: 
+      background: 0
+      circle_a: 1
+      circle_b: 2
+      circle_c: 3
 fields: 
   original_vertex_ids: 
     topology: "topo"