Backport: Adding cone primitives. (#621)

Signed-off-by: Benjamin Perseghetti <bperseghetti@rudislabs.com>

Author: bperseghetti

src/plugins/marker_manager/MarkerManager.cc

@@ -610,6 +610,8 @@ gz::rendering::MarkerType MarkerManagerPrivate::MsgToType(
       return gz::rendering::MarkerType::MT_BOX;
     case gz::msgs::Marker::CAPSULE:
       return gz::rendering::MarkerType::MT_CAPSULE;
+    case gz::msgs::Marker::CONE:
+      return gz::rendering::MarkerType::MT_CONE;
     case gz::msgs::Marker::CYLINDER:
       return gz::rendering::MarkerType::MT_CYLINDER;
     case gz::msgs::Marker::LINE_STRIP:

src/plugins/transport_scene_manager/TransportSceneManager.cc

@@ -687,6 +687,13 @@ rendering::GeometryPtr TransportSceneManagerPrivate::LoadGeometry(
     if (_msg.box().has_size())
       scale = msgs::Convert(_msg.box().size());
   }
+  else if (_msg.has_cone())
+  {
+    geom = this->scene->CreateCone();
+    scale.X() = _msg.cone().radius() * 2;
+    scale.Y() = scale.X();
+    scale.Z() = _msg.cone().length();
+  }
   else if (_msg.has_cylinder())
   {
     geom = this->scene->CreateCylinder();