strike-through wip : we can't remove plugDirtied stuff though

include/GafferUI/StandardNodeGadget.h

@@ -169,7 +169,7 @@ class GAFFERUI_API StandardNodeGadget : public NodeGadget
 		void error( const Gaffer::Plug *plug, const Gaffer::Plug *source, const std::string &message );
 		void displayError( Gaffer::ConstPlugPtr plug, const std::string &message );
 
-		bool m_nodeEnabled;
+		bool m_nodeAlwaysDisabled;
 		bool m_labelsVisibleOnHover;
 		// We accept drags onto the NodeGadget itself and
 		// use them to create a connection to the

src/GafferUI/StandardNodeGadget.cpp

@@ -522,7 +522,7 @@ StandardNodeGadget::StandardNodeGadget( Gaffer::NodePtr node )
 // can optionally use it without needing to inherit from StandardNodeGadget
 StandardNodeGadget::StandardNodeGadget( Gaffer::NodePtr node, bool auxiliary  )
 	:	NodeGadget( node ),
-		m_nodeEnabled( true ),
+		m_nodeAlwaysDisabled( false ),
 		m_labelsVisibleOnHover( true ),
 		m_dragDestination( nullptr ),
 		m_userColor( 0 ),
@@ -659,7 +659,6 @@ StandardNodeGadget::StandardNodeGadget( Gaffer::NodePtr node, bool auxiliary  )
 	updateUserColor();
 	updateMinWidth();
 	updatePadding();
-	updateNodeEnabled();
 	updateIcon();
 	updateShape();
 	updateFocusGadgetVisibility();
@@ -715,7 +714,7 @@ void StandardNodeGadget::renderLayer( Layer layer, const Style *style, RenderRea
 		{
 			const Box3f b = bound();
 
-			if( !m_nodeEnabled && !isSelectionRender( reason ) )
+			if( m_nodeAlwaysDisabled && !isSelectionRender( reason ) )
 			{
 				/// \todo Replace renderLine() with a specific method (renderNodeStrikeThrough?) on the Style class
 				/// so that styles can do customised drawing based on knowledge of what is being drawn.
@@ -776,6 +775,16 @@ void StandardNodeGadget::updateFromContextTracker( const ContextTracker *context
 {
 	NodeGadget::updateFromContextTracker( contextTracker );
 	updateTextDimming();
+
+	if( auto dependencyNode = IECore::runTimeCast<const DependencyNode>( node() ) )
+	{
+		const bool alwaysDisabled = contextTracker->isAlwaysDisabled( dependencyNode );
+		if( alwaysDisabled != m_nodeAlwaysDisabled )
+		{
+			m_nodeAlwaysDisabled = alwaysDisabled;
+			dirty( DirtyType::Render );
+		}
+	}
 }
 
 void StandardNodeGadget::updateTextDimming()
@@ -1035,7 +1044,6 @@ bool StandardNodeGadget::getLabelsVisibleOnHover() const
 
 void StandardNodeGadget::plugDirtied( const Gaffer::Plug *plug )
 {
-	updateNodeEnabled( plug );
 	if( ErrorGadget *e = errorGadget( /* createIfMissing = */ false ) )
 	{
 		e->removeError( plug );
@@ -1260,46 +1268,6 @@ void StandardNodeGadget::updatePadding()
 	paddingRow()->setPadding( Box3f( V3f( -padding ), V3f( padding ) ) );
 }
 
-void StandardNodeGadget::updateNodeEnabled( const Gaffer::Plug *dirtiedPlug )
-{
-	DependencyNode *dependencyNode = IECore::runTimeCast<DependencyNode>( node() );
-	if( !dependencyNode )
-	{
-		return;
-	}
-
-	const Gaffer::BoolPlug *enabledPlug = dependencyNode->enabledPlug();
-	if( !enabledPlug )
-	{
-		return;
-	}
-
-	if( dirtiedPlug && dirtiedPlug != enabledPlug )
-	{
-		return;
-	}
-
-	const ValuePlug *source = enabledPlug->source<ValuePlug>();
-	bool enabled = true;
-	if( source->direction() != Plug::Out || !IECore::runTimeCast<const ComputeNode>( source->node() ) )
-	{
-		// Only evaluate `enabledPlug` if it won't trigger a compute.
-		// We don't want to hang the UI waiting, and we don't really
-		// know what context to perform the compute in anyway.
-		/// \todo We could consider doing this in the background, using
-		/// an upstream traversal from the focus node to determine context.
-		enabled = enabledPlug->getValue();
-	}
-
-	if( enabled == m_nodeEnabled )
-	{
-		return;
-	}
-
-	m_nodeEnabled = enabled;
-	dirty( DirtyType::Render );
-}
-
 void StandardNodeGadget::updateIcon()
 {
 	float scale = 1.5f;