From 76addecde6ee2f93a40a2483ad1c747284ae7df4 Mon Sep 17 00:00:00 2001
From: Matthew Mott <orbweaver3d@gmail.com>
Date: Sun, 12 Dec 2021 14:05:20 +0000
Subject: [PATCH] GenericEntityNode now uses observeKey() with
 auto-disconnection

---
 radiantcore/entity/AngleKey.h                 |  7 +++--
 .../entity/generic/GenericEntityNode.cpp      | 31 +++++--------------
 .../entity/generic/GenericEntityNode.h        | 14 ++++++---
 3 files changed, 22 insertions(+), 30 deletions(-)

diff --git a/radiantcore/entity/AngleKey.h b/radiantcore/entity/AngleKey.h
index fdeb6700b7..c26201a262 100644
--- a/radiantcore/entity/AngleKey.h
+++ b/radiantcore/entity/AngleKey.h
@@ -9,7 +9,8 @@ class Entity;
 namespace entity
 {
 
-class AngleKey
+/// Wrapper for an "angle" spawnarg
+class AngleKey: public sigc::trackable
 {
 private:
 	std::function<void()> _angleChanged;
@@ -19,8 +20,8 @@ class AngleKey
 public:
     static const float IDENTITY;
 
-    AngleKey(const std::function<void()>& angleChanged) : 
-        _angleChanged(angleChanged), 
+    AngleKey(const std::function<void()>& angleChanged) :
+        _angleChanged(angleChanged),
         _value(IDENTITY)
     {}
 
diff --git a/radiantcore/entity/generic/GenericEntityNode.cpp b/radiantcore/entity/generic/GenericEntityNode.cpp
index 5bc540a916..1183f19f54 100644
--- a/radiantcore/entity/generic/GenericEntityNode.cpp
+++ b/radiantcore/entity/generic/GenericEntityNode.cpp
@@ -37,19 +37,6 @@ GenericEntityNode::GenericEntityNode(const GenericEntityNode& other) :
 
 GenericEntityNode::~GenericEntityNode()
 {
-	if (!_allow3Drotations)
-	{
-		// Ordinary rotation (2D around z axis), use angle key observer
-		removeKeyObserver("angle", _angleObserver);
-	}
-	else
-	{
-		// Full 3D rotations allowed, observe both keys using the rotation key observer
-		removeKeyObserver("angle", _angleObserver);
-		removeKeyObserver("rotation", _rotationObserver);
-	}
-
-	removeKeyObserver("origin", m_originKey);
 }
 
 GenericEntityNodePtr GenericEntityNode::Create(const IEntityClassPtr& eclass)
@@ -71,22 +58,20 @@ void GenericEntityNode::construct()
 
 	if (!_allow3Drotations)
 	{
-		_angleObserver.setCallback(std::bind(&AngleKey::angleChanged, &m_angleKey, std::placeholders::_1));
-
 		// Ordinary rotation (2D around z axis), use angle key observer
-		addKeyObserver("angle", _angleObserver);
+        static_assert(std::is_base_of<sigc::trackable, AngleKey>::value);
+		observeKey("angle", sigc::mem_fun(m_angleKey, &AngleKey::angleChanged));
 	}
 	else
 	{
-		_angleObserver.setCallback(std::bind(&RotationKey::angleChanged, &m_rotationKey, std::placeholders::_1));
-		_rotationObserver.setCallback(std::bind(&RotationKey::rotationChanged, &m_rotationKey, std::placeholders::_1));
-
 		// Full 3D rotations allowed, observe both keys using the rotation key observer
-		addKeyObserver("angle", _angleObserver);
-		addKeyObserver("rotation", _rotationObserver);
-	}
+        static_assert(std::is_base_of<sigc::trackable, RotationKey>::value);
+		observeKey("angle", sigc::mem_fun(m_rotationKey, &RotationKey::angleChanged));
+        observeKey("rotation", sigc::mem_fun(m_rotationKey, &RotationKey::rotationChanged));
+    }
 
-	addKeyObserver("origin", m_originKey);
+    static_assert(std::is_base_of<sigc::trackable, OriginKey>::value);
+	observeKey("origin", sigc::mem_fun(m_originKey, &OriginKey::onKeyValueChanged));
 }
 
 void GenericEntityNode::snapto(float snap)
diff --git a/radiantcore/entity/generic/GenericEntityNode.h b/radiantcore/entity/generic/GenericEntityNode.h
index 9e317d0b03..dd6893a4f0 100644
--- a/radiantcore/entity/generic/GenericEntityNode.h
+++ b/radiantcore/entity/generic/GenericEntityNode.h
@@ -24,7 +24,16 @@ namespace entity
 class GenericEntityNode;
 typedef std::shared_ptr<GenericEntityNode> GenericEntityNodePtr;
 
-/// EntityNode subclass for all entity types not handled by a specific class
+
+/**
+ * @brief EntityNode subclass for all entity types not handled by a specific
+ * class.
+ *
+ * Generic entity nodes represent entities which have no editor-specific
+ * functionality, beyond simply existing and pointing in a particular direction.
+ * They are rendered as boxes with an angle/rotation arrow. Common generic
+ * entities include "info_playerstart" and "info_location".
+ */
 class GenericEntityNode: public EntityNode, public Snappable
 {
 	OriginKey m_originKey;
@@ -53,9 +62,6 @@ class GenericEntityNode: public EntityNode, public Snappable
 	// FALSE if the arrow is caught in the xy plane
 	bool _allow3Drotations;
 
-	KeyObserverDelegate _rotationObserver;
-	KeyObserverDelegate _angleObserver;
-
     // Whether to draw a solid/shaded box in full material render mode or just the wireframe
     enum SolidAAABBRenderMode
     {