Add some signals to Entity

dart/dynamics/Entity.cpp

@@ -64,9 +64,15 @@ Entity::~Entity()
 }
 
 //==============================================================================
-const std::string& Entity::setName(const std::string &_name)
+const std::string& Entity::setName(const std::string& _name)
 {
+  if (mName == _name)
+    return mName;
+
+  const std::string oldName = mName;
   mName = _name;
+  mNameChangedSignal.raise(this, oldName, mName);
+
   return mName;
 }
 
@@ -80,6 +86,8 @@ const std::string& Entity::getName() const
 void Entity::addVisualizationShape(Shape* _p)
 {
   mVizShapes.push_back(_p);
+
+  mVizShapeAddedSignal.raise(this, _p);
 }
 
 //==============================================================================
@@ -153,6 +161,10 @@ bool Entity::isQuiet() const
 void Entity::notifyTransformUpdate()
 {
   mNeedTransformUpdate = true;
+
+  // The actual transform hasn't updated yet. But when its getter is called,
+  // the transformation will be updated automatically.
+  mTransformUpdatedSignal.raise(this);
 }
 
 //==============================================================================
@@ -165,6 +177,10 @@ bool Entity::needsTransformUpdate() const
 void Entity::notifyVelocityUpdate()
 {
   mNeedVelocityUpdate = true;
+
+  // The actual velocity hasn't updated yet. But when its getter is called,
+  // the velocity will be updated automatically.
+  mVelocityChangedSignal.raise(this);
 }
 
 //==============================================================================
@@ -177,6 +193,10 @@ bool Entity::needsVelocityUpdate() const
 void Entity::notifyAccelerationUpdate()
 {
   mNeedAccelerationUpdate = true;
+
+  // The actual acceleration hasn't updated yet. But when its getter is called,
+  // the acceleration will be updated automatically.
+  mAccelerationChangedSignal.raise(this);
 }
 
 //==============================================================================
@@ -185,35 +205,70 @@ bool Entity::needsAccelerationUpdate() const
   return mNeedAccelerationUpdate;
 }
 
+//==============================================================================
+common::Connection Entity::connectFrameChanged(const FrameChangedSlot& _slot)
+{
+  return mFrameChangedSignal.connect(_slot);
+}
+
+//==============================================================================
+common::Connection Entity::connectNameChanged(const NameChangedSlot& _slot)
+{
+  return mNameChangedSignal.connect(_slot);
+}
+
+//==============================================================================
+common::Connection Entity::connectVizShapeAdded(const VizShapeAddedSlot& _slot)
+{
+  return mVizShapeAddedSignal.connect(_slot);
+}
+
+//==============================================================================
+common::Connection Entity::connectTransformChanged(const EntitySlot& _slot)
+{
+  return mTransformUpdatedSignal.connect(_slot);
+}
+
+//==============================================================================
+common::Connection Entity::connectVelocityChanged(const EntitySlot& _slot)
+{
+  return mVelocityChangedSignal.connect(_slot);
+}
+
+//==============================================================================
+common::Connection Entity::connectAccelerationChanged(const EntitySlot& _slot)
+{
+  return mAccelerationChangedSignal.connect(_slot);
+}
+
 //==============================================================================
 void Entity::changeParentFrame(Frame* _newParentFrame)
 {
-  if(!mAmQuiet)
+  if (mParentFrame == _newParentFrame)
+    return;
+
+  const Frame* oldParentFrame = mParentFrame;
+
+  if (!mAmQuiet && nullptr != mParentFrame)
   {
-    if(mParentFrame)
+    EntityPtrSet::iterator it = mParentFrame->mChildEntities.find(this);
+    if (it != mParentFrame->mChildEntities.end())
     {
-      EntityPtrSet::iterator it = mParentFrame->mChildEntities.find(this);
-      if(it != mParentFrame->mChildEntities.end())
-      {
-        mParentFrame->mChildEntities.erase(it);
-        mParentFrame->processRemovedEntity(this);
-      }
+      mParentFrame->mChildEntities.erase(it);
+      mParentFrame->processRemovedEntity(this);
     }
   }
 
-  if(NULL == _newParentFrame)
-  {
-    mParentFrame = NULL;
-    return;
-  }
-
   mParentFrame =_newParentFrame;
-  if(!mAmQuiet)
+
+  if (!mAmQuiet && nullptr != mParentFrame)
   {
     mParentFrame->mChildEntities.insert(this);
     mParentFrame->processNewEntity(this);
     notifyTransformUpdate();
   }
+
+  mFrameChangedSignal.raise(this, oldParentFrame, mParentFrame);
 }
 
 //==============================================================================

dart/dynamics/Entity.h

@@ -41,6 +41,7 @@
 #include <string>
 #include <vector>
 
+#include "dart/common/Signal.h"
 #include "dart/dynamics/Shape.h"
 
 namespace dart {
@@ -128,6 +129,48 @@ class Entity
   /// Returns true iff an acceleration update is needed for this Entity
   bool needsAccelerationUpdate() const;
 
+  //----------------------------------------------------------------------------
+  /// \{ \name Signals
+  //----------------------------------------------------------------------------
+
+  using EntitySignal = common::Signal<void(const Entity*)>;
+  using FrameChangedSignal
+      = common::Signal<void(const Entity*,
+                            const Frame* _oldFrame,
+                            const Frame* _newFrame)>;
+  using NameChangedSignal
+      = common::Signal<void(const Entity*,
+                            const std::string& _oldName,
+                            const std::string& _newFrame)>;
+  using VizShapeAddedSignal
+      = common::Signal<void(const Entity*,
+                            const Shape* _newVisShape)>;
+
+  using EntitySlot = EntitySignal::SlotType;
+  using FrameChangedSlot = FrameChangedSignal::SlotType;
+  using NameChangedSlot = NameChangedSignal::SlotType;
+  using VizShapeAddedSlot = VizShapeAddedSignal::SlotType;
+
+  /// Connect slot to frame changed signal
+  common::Connection connectFrameChanged(const FrameChangedSlot& _slot);
+
+  /// Connect slot to name changed signal
+  common::Connection connectNameChanged(const NameChangedSlot& _slot);
+
+  /// Connect slot to visualization changed signal
+  common::Connection connectVizShapeAdded(const VizShapeAddedSlot& _slot);
+
+  /// Connect slot to transform changed signal
+  common::Connection connectTransformChanged(const EntitySlot& _slot);
+
+  /// Connect slot to velocity changed signal
+  common::Connection connectVelocityChanged(const EntitySlot& _slot);
+
+  /// Connect slot to acceleration changed signal
+  common::Connection connectAccelerationChanged(const EntitySlot& _slot);
+
+  /// \}
+
 protected:
   /// Used by derived classes to change their parent frames
   virtual void changeParentFrame(Frame* _newParentFrame);
@@ -151,6 +194,24 @@ class Entity
   /// Does this Entity need an Acceleration update
   mutable bool mNeedAccelerationUpdate;
 
+  /// Frame changed signal
+  FrameChangedSignal mFrameChangedSignal;
+
+  /// Name changed signal
+  NameChangedSignal mNameChangedSignal;
+
+  /// Visualization added signal
+  VizShapeAddedSignal mVizShapeAddedSignal;
+
+  /// Transform changed signal
+  EntitySignal mTransformUpdatedSignal;
+
+  /// Velocity changed signal
+  EntitySignal mVelocityChangedSignal;
+
+  /// Acceleration changed signal
+  EntitySignal mAccelerationChangedSignal;
+
 private:
   /// Whether or not this Entity is set to be quiet
   const bool mAmQuiet;
@@ -163,8 +224,7 @@ class Detachable : public virtual Entity
 {
 public:
   /// Constructor
-  explicit Detachable(Frame* _refFrame, const std::string& _name,
-                      bool _quiet);
+  explicit Detachable(Frame* _refFrame, const std::string& _name, bool _quiet);
 
   /// Allows the user to change the parent Frame of this Entity
   virtual void setParentFrame(Frame* _newParentFrame);

dart/dynamics/Frame.cpp

@@ -474,6 +474,8 @@ void Frame::notifyTransformUpdate()
 
   for(Entity* entity : mChildEntities)
     entity->notifyTransformUpdate();
+
+  mTransformUpdatedSignal.raise(this);
 }
 
 //==============================================================================
@@ -489,6 +491,8 @@ void Frame::notifyVelocityUpdate()
 
   for(Entity* entity : mChildEntities)
     entity->notifyVelocityUpdate();
+
+  mVelocityChangedSignal.raise(this);
 }
 
 //==============================================================================
@@ -502,11 +506,16 @@ void Frame::notifyAccelerationUpdate()
 
   for(Entity* entity : mChildEntities)
     entity->notifyAccelerationUpdate();
+
+  mAccelerationChangedSignal.raise(this);
 }
 
 //==============================================================================
 void Frame::changeParentFrame(Frame* _newParentFrame)
 {
+  if (mParentFrame == _newParentFrame)
+    return;
+
   if(_newParentFrame)
   {
     if(_newParentFrame->descendsFrom(this))

dart/dynamics/Frame.h

@@ -232,22 +232,23 @@ class Frame : public virtual Entity
   //--------------------------------------------------------------------------
 
   // Render this Frame as well as any Entities it contains
-  virtual void draw(renderer::RenderInterface *_ri = NULL,
-                    const Eigen::Vector4d &_color = Eigen::Vector4d::Ones(),
-                    bool _useDefaultColor = true, int _depth = 0) const;
+  virtual void draw(
+      renderer::RenderInterface *_ri = NULL,
+      const Eigen::Vector4d &_color = Eigen::Vector4d::Ones(),
+      bool _useDefaultColor = true, int _depth = 0) const override;
 
   /// Notify this Frame and all its children that its pose has changed
-  virtual void notifyTransformUpdate();
+  virtual void notifyTransformUpdate() override;
 
   /// Notify this Frame and all its children that its velocity has changed
-  virtual void notifyVelocityUpdate();
+  virtual void notifyVelocityUpdate() override;
 
   /// Notify this Frame and all its children that its acceleration has changed
-  virtual void notifyAccelerationUpdate();
+  virtual void notifyAccelerationUpdate() override;
 
 protected:
   // Documentation inherited
-  virtual void changeParentFrame(Frame* _newParentFrame);
+  virtual void changeParentFrame(Frame* _newParentFrame) override;
 
   /// Called during a parent Frame change to allow extensions of the Frame class
   /// to handle new children in customized ways. This function is a no op unless