Support emitting an event on play/pause/step

include/ignition/gui/GuiEvents.hh

@@ -27,6 +27,7 @@
 #include <ignition/common/MouseEvent.hh>
 #include <ignition/math/Vector2.hh>
 #include <ignition/math/Vector3.hh>
+#include <ignition/msgs/world_control.pb.h>
 #include <ignition/utils/ImplPtr.hh>
 
 #include "ignition/gui/Export.hh"
@@ -449,6 +450,25 @@ namespace ignition
         /// \brief Private data pointer
         IGN_UTILS_IMPL_PTR(dataPtr)
       };
+
+      /// \brief Event which is called to share WorldControl information.
+      class IGNITION_GUI_VISIBLE WorldControl : public QEvent
+      {
+        /// \brief Constructor
+        /// \param[in] _worldControl The WorldControl information
+        public: explicit WorldControl(const msgs::WorldControl &_worldControl);
+
+        /// \brief Unique type for this event.
+        static const QEvent::Type kType = QEvent::Type(QEvent::MaxUser - 19);
+
+        /// \brief Get the WorldControl information
+        /// \return The WorldControl information
+        public: const msgs::WorldControl &WorldControlInfo() const;
+
+        /// \internal
+        /// \brief Private data pointer
+        IGN_UTILS_IMPL_PTR(dataPtr)
+      };
     }
   }
 }

src/GuiEvents.cc

@@ -136,6 +136,12 @@ class ignition::gui::events::MousePressOnScene::Implementation
   public: common::MouseEvent mouse;
 };
 
+class ignition::gui::events::WorldControl::Implementation
+{
+  /// \brief WorldControl information.
+  public: msgs::WorldControl worldControl;
+};
+
 using namespace ignition;
 using namespace gui;
 using namespace events;
@@ -401,3 +407,16 @@ const common::MouseEvent &MousePressOnScene::Mouse() const
 {
   return this->dataPtr->mouse;
 }
+
+/////////////////////////////////////////////////
+WorldControl::WorldControl(const msgs::WorldControl &_worldControl)
+  : QEvent(kType), dataPtr(utils::MakeImpl<Implementation>())
+{
+  this->dataPtr->worldControl = _worldControl;
+}
+
+/////////////////////////////////////////////////
+const msgs::WorldControl &WorldControl::WorldControlInfo() const
+{
+  return this->dataPtr->worldControl;
+}

src/GuiEvents_TEST.cc

@@ -254,3 +254,32 @@ TEST(GuiEventsTest, MousePressOnScene)
   EXPECT_TRUE(event.Mouse().Alt());
   EXPECT_FALSE(event.Mouse().Shift());
 }
+
+/////////////////////////////////////////////////
+TEST(GuiEventsTest, WorldControl)
+{
+  ignition::msgs::WorldControl worldControl;
+  worldControl.set_pause(true);
+  worldControl.set_step(true);
+  worldControl.set_multi_step(5u);
+  worldControl.mutable_reset()->set_all(true);
+  worldControl.mutable_reset()->set_time_only(true);
+  worldControl.mutable_reset()->set_model_only(false);
+  worldControl.set_seed(10u);
+  worldControl.mutable_run_to_sim_time()->set_sec(2);
+  worldControl.mutable_run_to_sim_time()->set_nsec(3);
+  events::WorldControl playEvent(worldControl);
+
+  EXPECT_LT(QEvent::User, playEvent.type());
+  EXPECT_FALSE(playEvent.WorldControlInfo().has_header());
+  EXPECT_TRUE(playEvent.WorldControlInfo().pause());
+  EXPECT_TRUE(playEvent.WorldControlInfo().step());
+  EXPECT_EQ(5u, playEvent.WorldControlInfo().multi_step());
+  EXPECT_FALSE(playEvent.WorldControlInfo().reset().has_header());
+  EXPECT_TRUE(playEvent.WorldControlInfo().reset().all());
+  EXPECT_TRUE(playEvent.WorldControlInfo().reset().time_only());
+  EXPECT_FALSE(playEvent.WorldControlInfo().reset().model_only());
+  EXPECT_EQ(10u, playEvent.WorldControlInfo().seed());
+  EXPECT_EQ(2, playEvent.WorldControlInfo().run_to_sim_time().sec());
+  EXPECT_EQ(3, playEvent.WorldControlInfo().run_to_sim_time().nsec());
+}

src/plugins/world_control/CMakeLists.txt

@@ -1,9 +1,19 @@
-ign_gui_add_plugin(WorldControl
-  SOURCES
-    WorldControl.cc
-  QT_HEADERS
-    WorldControl.hh
-  TEST_SOURCES
-    WorldControl_TEST.cc
-)
-
+if (NOT MSVC)
+  ign_gui_add_plugin(WorldControl
+    SOURCES
+      WorldControl.cc
+      WorldControlEventListener.cc
+    QT_HEADERS
+      WorldControl.hh
+      WorldControlEventListener.hh
+    TEST_SOURCES
+      WorldControl_TEST.cc
+  )
+else()
+  ign_gui_add_plugin(WorldControl
+    SOURCES
+      WorldControl.cc
+    QT_HEADERS
+      WorldControl.hh
+  )
+endif()

src/plugins/world_control/WorldControl.cc

@@ -24,7 +24,10 @@
 #include <ignition/common/StringUtils.hh>
 #include <ignition/plugin/Register.hh>
 
+#include "ignition/gui/Application.hh"
 #include "ignition/gui/Helpers.hh"
+#include "ignition/gui/GuiEvents.hh"
+#include "ignition/gui/MainWindow.hh"
 
 namespace ignition
 {
@@ -34,6 +37,10 @@ namespace plugins
 {
   class WorldControlPrivate
   {
+    /// \brief Send the world control event or call the control service.
+    /// \param[in] _msg Message to send.
+    public: void SendEventMsg(const ignition::msgs::WorldControl &_msg);
+
     /// \brief Message holding latest world statistics
     public: ignition::msgs::WorldStatistics msg;
 
@@ -51,6 +58,15 @@ namespace plugins
 
     /// \brief True for paused
     public: bool pause{true};
+
+    /// \brief The paused state of the most recently received world stats msg
+    /// (true for paused)
+    public: bool lastStatsMsgPaused{true};
+
+    /// \brief Whether server communication should occur through an event (true)
+    /// or service (false). The service option is used by default for
+    /// ign-gui6, and should be changed to use the event by default in ign-gui7.
+    public: bool useEvent{false};
   };
 }
 }
@@ -151,6 +167,7 @@ void WorldControl::LoadConfig(const tinyxml2::XMLElement *_pluginElem)
         pausedElem->QueryBoolText(&startPaused);
       }
       this->dataPtr->pause = startPaused;
+      this->dataPtr->lastStatsMsgPaused = startPaused;
       if (startPaused)
         this->paused();
       else
@@ -212,18 +229,41 @@ void WorldControl::LoadConfig(const tinyxml2::XMLElement *_pluginElem)
     ignerr << "Failed to create valid topic for world [" << worldName << "]"
            << std::endl;
   }
+
+  if (auto elem = _pluginElem->FirstChildElement("use_event"))
+    elem->QueryBoolText(&this->dataPtr->useEvent);
+
+  if (this->dataPtr->useEvent)
+    igndbg << "Using an event to share WorldControl msgs with the server\n";
+  else
+    igndbg << "Using a service to share WorldControl msgs with the server\n";
 }
 
 /////////////////////////////////////////////////
 void WorldControl::ProcessMsg()
 {
   std::lock_guard<std::recursive_mutex> lock(this->dataPtr->mutex);
 
-  if (!this->dataPtr->pause && this->dataPtr->msg.paused())
+  // ignore the message if it's associated with a step
+  const auto &header = this->dataPtr->msg.header();
+  if ((header.data_size() > 0) && (header.data(0).key() == "step"))
+    return;
+
+  // If the pause state of the message doesn't match the pause state of this
+  // plugin, then play/pause must have occurred elsewhere (for example, the
+  // command line). If the pause state of the message matches the pause state
+  // of this plugin, but the pause state of the message differs from the
+  // previous message's pause state, this means that a pause/play request from
+  // this plugin has been registered by the server
+  if (this->dataPtr->msg.paused() &&
+      (!this->dataPtr->pause || !this->dataPtr->lastStatsMsgPaused))
     this->paused();
-  else if (this->dataPtr->pause && !this->dataPtr->msg.paused())
+  else if (!this->dataPtr->msg.paused() &&
+      (this->dataPtr->pause || this->dataPtr->lastStatsMsgPaused))
     this->playing();
+
   this->dataPtr->pause = this->dataPtr->msg.paused();
+  this->dataPtr->lastStatsMsgPaused = this->dataPtr->msg.paused();
 }
 
 /////////////////////////////////////////////////
@@ -238,33 +278,20 @@ void WorldControl::OnWorldStatsMsg(const ignition::msgs::WorldStatistics &_msg)
 /////////////////////////////////////////////////
 void WorldControl::OnPlay()
 {
-  std::function<void(const ignition::msgs::Boolean &, const bool)> cb =
-      [this](const ignition::msgs::Boolean &/*_rep*/, const bool _result)
-  {
-    if (_result)
-      QMetaObject::invokeMethod(this, "playing");
-  };
-
-  ignition::msgs::WorldControl req;
-  req.set_pause(false);
+  ignition::msgs::WorldControl msg;
+  msg.set_pause(false);
   this->dataPtr->pause = false;
-  this->dataPtr->node.Request(this->dataPtr->controlService, req, cb);
+  this->dataPtr->SendEventMsg(msg);
 }
 
 /////////////////////////////////////////////////
 void WorldControl::OnPause()
 {
-  std::function<void(const ignition::msgs::Boolean &, const bool)> cb =
-      [this](const ignition::msgs::Boolean &/*_rep*/, const bool _result)
-  {
-    if (_result)
-      QMetaObject::invokeMethod(this, "paused");
-  };
-
-  ignition::msgs::WorldControl req;
-  req.set_pause(true);
+  ignition::msgs::WorldControl msg;
+  msg.set_pause(true);
   this->dataPtr->pause = true;
-  this->dataPtr->node.Request(this->dataPtr->controlService, req, cb);
+
+  this->dataPtr->SendEventMsg(msg);
 }
 
 /////////////////////////////////////////////////
@@ -276,15 +303,31 @@ void WorldControl::OnStepCount(const unsigned int _steps)
 /////////////////////////////////////////////////
 void WorldControl::OnStep()
 {
-  std::function<void(const ignition::msgs::Boolean &, const bool)> cb =
-      [](const ignition::msgs::Boolean &/*_rep*/, const bool /*_result*/)
-  {
-  };
+  ignition::msgs::WorldControl msg;
+  msg.set_pause(this->dataPtr->pause);
+  msg.set_multi_step(this->dataPtr->multiStep);
 
-  ignition::msgs::WorldControl req;
-  req.set_pause(this->dataPtr->pause);
-  req.set_multi_step(this->dataPtr->multiStep);
-  this->dataPtr->node.Request(this->dataPtr->controlService, req, cb);
+  this->dataPtr->SendEventMsg(msg);
+}
+
+/////////////////////////////////////////////////
+void WorldControlPrivate::SendEventMsg(const ignition::msgs::WorldControl &_msg)
+{
+  if (this->useEvent)
+  {
+    gui::events::WorldControl event(_msg);
+    App()->sendEvent(App()->findChild<MainWindow *>(), &event);
+  }
+  else
+  {
+    std::function<void(const ignition::msgs::Boolean &, const bool)> cb =
+        [](const ignition::msgs::Boolean &/*_rep*/, const bool /*_result*/)
+    {
+      // the service CB is empty because updates are handled in
+      // WorldControl::ProcessMsg
+    };
+    this->node.Request(this->controlService, _msg, cb);
+  }
 }
 
 // Register this plugin

src/plugins/world_control/WorldControlEventListener.cc

@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2021 Open Source Robotics Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+*/
+
+#include "WorldControlEventListener.hh"
+
+using namespace ignition;
+using namespace gui;
+
+WorldControlEventListener::WorldControlEventListener()
+{
+  ignition::gui::App()->findChild<
+    ignition::gui::MainWindow *>()->installEventFilter(this);
+}
+
+WorldControlEventListener::~WorldControlEventListener() = default;
+
+bool WorldControlEventListener::eventFilter(QObject *_obj, QEvent *_event)
+{
+  if (_event->type() == ignition::gui::events::WorldControl::kType)
+  {
+    auto worldControlEvent =
+      reinterpret_cast<gui::events::WorldControl *>(_event);
+    if (worldControlEvent)
+    {
+      this->listenedToPlay = !worldControlEvent->WorldControlInfo().pause();
+      this->listenedToPause = worldControlEvent->WorldControlInfo().pause();
+      this->listenedToStep =
+        worldControlEvent->WorldControlInfo().multi_step() > 0u;
+    }
+  }
+
+  // Standard event processing
+  return QObject::eventFilter(_obj, _event);
+}