Support nested model

examples/worlds/nested_model.sdf

@@ -0,0 +1,110 @@
+<?xml version="1.0" ?>
+<sdf version="1.6">
+  <world name="nested_model_world">
+    <physics name="1ms" type="ignored">
+      <max_step_size>0.001</max_step_size>
+      <real_time_factor>1.0</real_time_factor>
+    </physics>
+    <plugin
+      filename="libignition-gazebo-physics-system.so"
+      name="ignition::gazebo::systems::Physics">
+      <engine><filename>libignition-physics-tpe-plugin.so</filename></engine>
+    </plugin>
+    <plugin
+      filename="libignition-gazebo-user-commands-system.so"
+      name="ignition::gazebo::systems::UserCommands">
+    </plugin>
+    <plugin
+      filename="libignition-gazebo-scene-broadcaster-system.so"
+      name="ignition::gazebo::systems::SceneBroadcaster">
+    </plugin>
+
+    <scene>
+      <ambient>1.0 1.0 1.0</ambient>
+      <background>0.8 0.8 0.8</background>
+    </scene>
+
+    <light type="directional" name="sun">
+      <cast_shadows>true</cast_shadows>
+      <pose>0 0 10 0 0 0</pose>
+      <diffuse>0.8 0.8 0.8 1</diffuse>
+      <specular>0.8 0.8 0.8 1</specular>
+      <attenuation>
+        <range>1000</range>
+        <constant>0.9</constant>
+        <linear>0.01</linear>
+        <quadratic>0.001</quadratic>
+      </attenuation>
+      <direction>-0.5 0.1 -0.9</direction>
+    </light>
+
+    <model name="ground_plane">
+      <static>true</static>
+      <link name="link">
+        <collision name="collision">
+          <geometry>
+            <plane>
+              <normal>0 0 1</normal>
+            </plane>
+          </geometry>
+        </collision>
+        <visual name="visual">
+          <geometry>
+            <plane>
+              <normal>0 0 1</normal>
+              <size>100 100</size>
+            </plane>
+          </geometry>
+          <material>
+            <ambient>0.8 0.8 0.8 1</ambient>
+            <diffuse>0.8 0.8 0.8 1</diffuse>
+            <specular>0.8 0.8 0.8 1</specular>
+          </material>
+        </visual>
+      </link>
+    </model>
+
+    <model name="model_00">
+      <pose>0 0 0.5 0 0 0</pose>
+      <link name="link_00">
+        <pose>0 0 0 0 0 0</pose>
+        <collision name="collision_00">
+          <geometry>
+            <sphere>
+              <radius>0.5</radius>
+            </sphere>
+          </geometry>
+        </collision>
+        <visual name="visual_00">
+          <geometry>
+            <sphere>
+              <radius>0.5</radius>
+            </sphere>
+          </geometry>
+        </visual>
+      </link>
+
+      <model name="model_01">
+        <pose>1 0 0.0 0 0 0</pose>
+        <link name="link_01">
+          <pose>0.25 0 0.0 0 0 0.785398</pose>
+          <collision name="collision_01">
+            <geometry>
+              <box>
+                <size>1 1 1</size>
+              </box>
+            </geometry>
+          </collision>
+          <visual name="visual_01">
+            <geometry>
+              <box>
+                <size>1 1 1</size>
+              </box>
+            </geometry>
+          </visual>
+        </link>
+      </model>
+    </model>
+
+  </world>
+</sdf>

include/ignition/gazebo/SdfEntityCreator.hh

@@ -155,6 +155,18 @@ namespace ignition
       /// \param[in] _parent Entity which should be _child's parent.
       public: void SetParent(Entity _child, Entity _parent);
 
+      /// \brief Overloaded function to recursively create model entities
+      /// and make sure a) only one canonical link is created per model tree,
+      /// and b) we override the nested model's static property to true if
+      /// its parent is static
+      /// \param[in] _model SDF model object.
+      /// \param[in] _createCanonicalLink True to create a canonical link
+      /// component and attach to its child link entity
+      /// \param[in] _staticParent True if parent is static, false otherwise.
+      /// \return Model entity.
+      private: Entity CreateEntities(const sdf::Model *_model,
+          bool _createCanonicalLink, bool _staticParent);
+
       /// \brief Pointer to private data.
       private: std::unique_ptr<SdfEntityCreatorPrivate> dataPtr;
     };

src/SdfEntityCreator.cc

@@ -216,6 +216,18 @@ Entity SdfEntityCreator::CreateEntities(const sdf::Model *_model)
 {
   IGN_PROFILE("SdfEntityCreator::CreateEntities(sdf::Model)");
 
+  // todo(anyone) Support multiple canonical links in nested models
+  // This version of CreateEntties keeps track whether or not to create a
+  // canonical link in a model tree using the second arg in this recursive
+  // function. We also override child nested models static property if parent
+  // model is static
+  return this->CreateEntities(_model, true, false);
+}
+
+//////////////////////////////////////////////////
+Entity SdfEntityCreator::CreateEntities(const sdf::Model *_model,
+    bool _createCanonicalLink, bool _staticParent)
+{
   // Entity
   Entity modelEntity = this->dataPtr->ecm->CreateEntity();
 
@@ -225,8 +237,9 @@ Entity SdfEntityCreator::CreateEntities(const sdf::Model *_model)
       components::Pose(ResolveSdfPose(_model->SemanticPose())));
   this->dataPtr->ecm->CreateComponent(modelEntity,
       components::Name(_model->Name()));
+  bool isStatic = _model->Static() || _staticParent;
   this->dataPtr->ecm->CreateComponent(modelEntity,
-      components::Static(_model->Static()));
+      components::Static(isStatic));
   this->dataPtr->ecm->CreateComponent(
       modelEntity, components::WindMode(_model->EnableWind()));
   this->dataPtr->ecm->CreateComponent(
@@ -238,18 +251,22 @@ Entity SdfEntityCreator::CreateEntities(const sdf::Model *_model)
   // the parent frame until we get frames working.
 
   // Links
+  bool canonicalLinkCreated = false;
   for (uint64_t linkIndex = 0; linkIndex < _model->LinkCount();
       ++linkIndex)
   {
     auto link = _model->LinkByIndex(linkIndex);
     auto linkEntity = this->CreateEntities(link);
 
     this->SetParent(linkEntity, modelEntity);
-    if ((_model->CanonicalLinkName().empty() && linkIndex == 0) ||
-        (link == _model->CanonicalLink()))
+
+    if (_createCanonicalLink &&
+        ((_model->CanonicalLinkName().empty() && linkIndex == 0) ||
+        (link == _model->CanonicalLink())))
     {
       this->dataPtr->ecm->CreateComponent(linkEntity,
           components::CanonicalLink());
+      canonicalLinkCreated = true;
     }
 
     // Set wind mode if the link didn't override it
@@ -270,6 +287,22 @@ Entity SdfEntityCreator::CreateEntities(const sdf::Model *_model)
     this->SetParent(jointEntity, modelEntity);
   }
 
+  // Nested Models
+  for (uint64_t modelIndex = 0; modelIndex < _model->ModelCount();
+      ++modelIndex)
+  {
+    auto nestedModel = _model->ModelByIndex(modelIndex);
+
+    // Create nested model. Make sure to only create canonical link component
+    // in the nested model if a canonical link has not been created in this
+    // model yet. Also override static propery of the nested model if this model
+    //  is static
+    auto nestedModelEntity = this->CreateEntities(nestedModel,
+        (_createCanonicalLink && !canonicalLinkCreated), isStatic);
+
+    this->SetParent(nestedModelEntity, modelEntity);
+  }
+
   // Model plugins
   this->dataPtr->eventManager->Emit<events::LoadPlugins>(modelEntity,
       _model->Element());

src/gui/plugins/component_inspector/ComponentInspector.cc

@@ -77,6 +77,9 @@ namespace ignition::gazebo
     /// \brief Entity type, such as 'world' or 'model'.
     public: QString type;
 
+    /// \brief Nested model or not
+    public: bool nestedModel = false;
+
     /// \brief Whether currently locked on a given entity
     public: bool locked{false};
 
@@ -308,6 +311,17 @@ void ComponentInspector::Update(const UpdateInfo &,
     if (typeId == components::Model::typeId)
     {
       this->SetType("model");
+
+      // check if entity is nested model
+      auto parentComp = _ecm.Component<components::ParentEntity>(
+           this->dataPtr->entity);
+      if (parentComp)
+      {
+        auto modelComp = _ecm.Component<components::Model>(parentComp->Data());
+        this->dataPtr->nestedModel = (modelComp);
+      }
+      this->NestedModelChanged();
+
       continue;
     }
 
@@ -687,6 +701,12 @@ void ComponentInspector::OnPose(double _x, double _y, double _z, double _roll,
   this->dataPtr->node.Request(poseCmdService, req, cb);
 }
 
+/////////////////////////////////////////////////
+bool ComponentInspector::NestedModel() const
+{
+  return this->dataPtr->nestedModel;
+}
+
 // Register this plugin
 IGNITION_ADD_PLUGIN(ignition::gazebo::ComponentInspector,
                     ignition::gui::Plugin)

src/gui/plugins/component_inspector/ComponentInspector.hh

@@ -178,6 +178,13 @@ namespace gazebo
       NOTIFY PausedChanged
     )
 
+    /// \brief Nested Model
+    Q_PROPERTY(
+      bool nestedModel
+      READ NestedModel
+      NOTIFY NestedModelChanged
+    )
+
     /// \brief Constructor
     public: ComponentInspector();
 
@@ -200,6 +207,13 @@ namespace gazebo
     public: Q_INVOKABLE void OnPose(double _x, double _y, double _z,
         double _roll, double _pitch, double _yaw);
 
+    /// \brief Get whether the entity is a nested model or not
+    /// \return True if the entity is a nested model, false otherwise
+    public: Q_INVOKABLE bool NestedModel() const;
+
+    /// \brief Notify that is nested model property has changed
+    signals: void NestedModelChanged();
+
     // Documentation inherited
     protected: bool eventFilter(QObject *_obj, QEvent *_event) override;
 

src/gui/plugins/component_inspector/ComponentInspector.qml

@@ -44,6 +44,11 @@ Rectangle {
    */
   property string entityType: ComponentInspector.type
 
+  /**
+   * Get if entity is nested model or not
+   */
+  property bool nestedModel : ComponentInspector.nestedModel
+
   /**
    * Light grey according to theme
    */

src/gui/plugins/component_inspector/Pose3d.qml

@@ -41,7 +41,7 @@ Rectangle {
   // Read-only / write
   property bool readOnly: {
     var isModel = entityType == "model"
-    return !(isModel)
+    return !(isModel) || nestedModel
   }
 
   // Loaded item for X