Added colourspace management to the image viewer.

The ImageView class allows arbitrary ImageProcessors to be registered as colour transforms, and chosen using a new "displayTransform" plug. The ocio.py config file registers a processor for each display transform in the OpenColorIO config, and a Default transform which tracks the global display transform specified via the preferences.

Fixes GafferHQ#573.

include/GafferImageUI/ImageView.h

@@ -48,6 +48,7 @@
 namespace GafferImage
 {
 
+IE_CORE_FORWARDDECLARE( ImageProcessor )
 IE_CORE_FORWARDDECLARE( Grade )
 IE_CORE_FORWARDDECLARE( ImageStats )
 IE_CORE_FORWARDDECLARE( ImagePlug )
@@ -73,6 +74,15 @@ class ImageView : public GafferUI::View
 		Gaffer::FloatPlug *gammaPlug();
 		const Gaffer::FloatPlug *gammaPlug() const;
 
+		/// Values should be names that exist in registeredDisplayTransforms().
+		Gaffer::StringPlug *displayTransformPlug();
+		const Gaffer::StringPlug *displayTransformPlug() const;
+
+		typedef boost::function<GafferImage::ImageProcessorPtr ()> DisplayTransformCreator;
+
+		static void registerDisplayTransform( const std::string &name, DisplayTransformCreator creator );
+		static void registeredDisplayTransforms( std::vector<std::string> &names );
+
 	protected :
 
 		/// May be called from a subclass constructor to add a converter
@@ -95,7 +105,14 @@ class ImageView : public GafferUI::View
 		GafferImage::Grade *gradeNode();
 		const GafferImage::Grade *gradeNode() const;
 
+		GafferImage::ImageProcessor *displayTransformNode();
+		const GafferImage::ImageProcessor *displayTransformNode() const;
+
 		void plugSet( Gaffer::Plug *plug );
+		void insertDisplayTransform();
+
+		typedef std::map<std::string, GafferImage::ImageProcessorPtr> DisplayTransformMap;
+		DisplayTransformMap m_displayTransforms;
 
 		int m_channelToView;
 		Imath::V2f m_mousePos;
@@ -104,6 +121,9 @@ class ImageView : public GafferUI::View
 		Imath::Color4f m_maxColor;
 		Imath::Color4f m_averageColor;
 
+		typedef std::map<std::string, DisplayTransformCreator> DisplayTransformCreatorMap;
+		static DisplayTransformCreatorMap &displayTransformCreators();
+
 		static ViewDescription<ImageView> g_viewDescription;
 
 		friend void GafferImageUIBindings::bindImageView();

src/GafferImageUI/ImageView.cpp

@@ -228,7 +228,6 @@ class ImageViewGadget : public GafferUI::Gadget
 				"void main()"
 				"{"
 				"	OUTCOLOR = texture2D( texture, gl_TexCoord[0].xy );"
-				"	OUTCOLOR = vec4( ieLinToSRGB( OUTCOLOR.r ), ieLinToSRGB( OUTCOLOR.g ), ieLinToSRGB( OUTCOLOR.b ), ieLinToSRGB( OUTCOLOR.a ) );"
 				"	if( channelToView==1 )"
 				"	{"
 				"		OUTCOLOR = vec4( OUTCOLOR[0], OUTCOLOR[0], OUTCOLOR[0], 1. );"
@@ -955,6 +954,8 @@ ImageView::ImageView( const std::string &name )
 	gradeNode->gammaPlug()->getChild( 1 )->setInput( gammaPlug );
 	gradeNode->gammaPlug()->getChild( 2 )->setInput( gammaPlug );
 
+	addChild( new StringPlug( "displayTransform", Plug::In, "", Plug::Default & ~Plug::AcceptsInputs ) );
+
 	ImagePlugPtr preprocessorOutput = new ImagePlug( "out", Plug::Out );
 	preprocessor->addChild( preprocessorOutput );
 	preprocessorOutput->setInput( gradeNode->outPlug() );
@@ -967,6 +968,9 @@ ImageView::ImageView( const std::string &name )
 
 	plugSetSignal().connect( boost::bind( &ImageView::plugSet, this, ::_1 ) );
 
+	// trigger insertDisplayTransform()
+
+	displayTransformPlug()->setValue( "Default" );
 }
 
 void ImageView::insertConverter( Gaffer::NodePtr converter )
@@ -1024,7 +1028,17 @@ const Gaffer::FloatPlug *ImageView::gammaPlug() const
 {
 	return getChild<FloatPlug>( "gamma" );
 }
-
+
+Gaffer::StringPlug *ImageView::displayTransformPlug()
+{
+	return getChild<StringPlug>( "displayTransform" );
+}
+
+const Gaffer::StringPlug *ImageView::displayTransformPlug() const
+{
+	return getChild<StringPlug>( "displayTransform" );
+}
+
 GafferImage::ImageStats *ImageView::imageStatsNode()
 {
 	return getChild<ImageStats>( "__imageStats" );
@@ -1100,5 +1114,74 @@ void ImageView::plugSet( Gaffer::Plug *plug )
 			g->multiplyPlug()->setValue( Color3f( m ) );
 		}
 	}
+	else if( plug == displayTransformPlug() )
+	{
+		insertDisplayTransform();
+	}
 }
 
+void ImageView::insertDisplayTransform()
+{
+	Grade *grade = gradeNode();
+	if( !grade )
+	{
+		/// \todo Remove this guard when we know no
+		/// subclasses are calling setPreprocessor.
+		return;
+	}
+
+	const std::string name = displayTransformPlug()->getValue();
+
+	ImageProcessorPtr displayTransform;
+	DisplayTransformMap::const_iterator it = m_displayTransforms.find( name );
+	if( it != m_displayTransforms.end() )
+	{
+		displayTransform = it->second;
+	}
+	else
+	{
+		DisplayTransformCreatorMap &m = displayTransformCreators();
+		DisplayTransformCreatorMap::const_iterator it = m.find( displayTransformPlug()->getValue() );
+		if( it != m.end() )
+		{
+			displayTransform = it->second();
+		}
+		if( displayTransform )
+		{
+			m_displayTransforms[name] = displayTransform;
+			displayTransform->setName( name );
+			getPreprocessor<Node>()->addChild( displayTransform );
+		}
+	}
+
+	if( displayTransform )
+	{
+		displayTransform->inPlug()->setInput( grade->outPlug() );
+		getPreprocessor<Node>()->getChild<Plug>( "out" )->setInput( displayTransform->outPlug() );
+	}
+	else
+	{
+		getPreprocessor<Node>()->getChild<Plug>( "out" )->setInput( grade->outPlug() );
+	}
+}		
+
+void ImageView::registerDisplayTransform( const std::string &name, DisplayTransformCreator creator )
+{
+	displayTransformCreators()[name] = creator;
+}
+
+void ImageView::registeredDisplayTransforms( std::vector<std::string> &names )
+{
+	const DisplayTransformCreatorMap &m = displayTransformCreators();
+	names.clear();
+	for( DisplayTransformCreatorMap::const_iterator it = m.begin(), eIt = m.end(); it != eIt; ++it )
+	{
+		names.push_back( it->first );
+	}
+}
+
+ImageView::DisplayTransformCreatorMap &ImageView::displayTransformCreators()
+{
+	static DisplayTransformCreatorMap g_creators;
+	return g_creators;
+}

src/GafferImageUIBindings/ImageViewBinding.cpp

@@ -38,12 +38,16 @@
 
 #include "GafferBindings/NodeBinding.h"
 
+#include "GafferImage/ImageProcessor.h"
+
 #include "GafferImageUI/ImageView.h"
 #include "GafferImageUIBindings/ImageViewBinding.h"
 
+using namespace std;
 using namespace boost::python;
 using namespace Gaffer;
 using namespace GafferBindings;
+using namespace GafferImage;
 using namespace GafferImageUI;
 
 class ImageViewWrapper : public NodeWrapper<ImageView>
@@ -65,13 +69,55 @@ class ImageViewWrapper : public NodeWrapper<ImageView>
 
 IE_CORE_DECLAREPTR( ImageViewWrapper );
 
+struct DisplayTransformCreator
+{
+	DisplayTransformCreator( object fn )
+		:	m_fn( fn )
+	{
+	}
+
+	ImageProcessorPtr operator()()
+	{
+		IECorePython::ScopedGILLock gilLock;
+		ImageProcessorPtr result = extract<ImageProcessorPtr>( m_fn() );
+		return result;
+	}
+
+	private :
+
+		object m_fn;
+
+};
+
+static void registerDisplayTransform( const std::string &name, object creator )
+{
+	ImageView::registerDisplayTransform( name, DisplayTransformCreator( creator ) );
+}
+
+static boost::python::list registeredDisplayTransforms()
+{
+	vector<string> n;
+	ImageView::registeredDisplayTransforms( n );
+	boost::python::list result;
+	for( vector<string>::const_iterator it = n.begin(), eIt = n.end(); it != eIt; ++it )
+	{
+		result.append( *it );
+	}
+
+	return result;
+}
+
 void GafferImageUIBindings::bindImageView()
 {
 
 	GafferBindings::NodeClass<ImageView, ImageViewWrapperPtr>()
 		/// \todo Remove deprecated input argument.
 		.def( init<const std::string &, Gaffer::PlugPtr>() )
 		.def( "_insertConverter", &ImageView::insertConverter )
+		.def( "registerDisplayTransform", &registerDisplayTransform )
+		.staticmethod( "registerDisplayTransform" )
+		.def( "registeredDisplayTransforms", &registeredDisplayTransforms )
+		.staticmethod( "registeredDisplayTransforms" )
 	;
 
 }

startup/gui/ocio.py

@@ -40,6 +40,7 @@
 
 import Gaffer
 import GafferUI
+import GafferImageUI
 
 # get default display setup
 
@@ -86,5 +87,43 @@ def __plugSet( plug ) :
 		return
 
 	__setDisplayTransform()
+	__updateDefaultDisplayTransforms()
 
 application.__ocioPlugSetConnection = preferences.plugSetSignal().connect( __plugSet )
+
+# register display transforms with the image viewer
+
+def __displayTransformCreator( name ) :
+
+	result = GafferImage.OpenColorIO()
+	result["inputSpace"].setValue( "linear" )
+	result["outputSpace"].setValue( config.getDisplayColorSpaceName( defaultDisplay, name ) )
+
+	return result
+
+for name in config.getViews( defaultDisplay ) :
+	GafferImageUI.ImageView.registerDisplayTransform( name, IECore.curry( __displayTransformCreator, name ) )
+
+# and register a special "Default" display transform which tracks the
+# global settings from the preferences
+
+__defaultDisplayTransforms = []
+
+def __updateDefaultDisplayTransforms() :
+
+	view = preferences["displayColorSpace"]["view"].getValue()
+	colorSpace = config.getDisplayColorSpaceName( defaultDisplay, view )
+	for node in __defaultDisplayTransforms :
+		node["outputSpace"].setValue( colorSpace )
+
+def __defaultDisplayTransformCreator() :
+
+	result = GafferImage.OpenColorIO()
+	result["inputSpace"].setValue( "linear" )
+
+	__defaultDisplayTransforms.append( result )
+	__updateDefaultDisplayTransforms()
+
+	return result
+
+GafferImageUI.ImageView.registerDisplayTransform( "Default", __defaultDisplayTransformCreator )