LightPositionTool : Add tool for placing shadows

Changes.md

@@ -9,6 +9,7 @@ Features
   - RenderPasses : Added a new node for appending render passes to the scene globals.
   - DeleteRenderPasses : Added a new node for removing render passes from the scene globals.
   - RenderPassWedge : Added a new node for causing upstream tasks to be dispatched in a range of contexts where the value of the `renderPass` context variable is varied based on the render pass names defined in the `renderPass:names` option.
+- LightPositionTool : Added tool to the scene viewer to place shadows. With a light selected, Control + Left Click will set the pivot point used for casting a shadow. Shift + Left Click sets the point to receive the shadow. The light is repositioned to be the same distance from the pivot, along the pivot-shadow point line, and oriented to face the shadow point.
 
 Improvements
 ------------

doc/source/Interface/ControlsAndShortcuts/index.md

@@ -223,6 +223,7 @@ Cycle Transform Tool Orientation     | {kbd}`O`
 Scale Tool                           | {kbd}`R`
 Camera Tool                          | {kbd}`T`
 Crop Window Tool                     | {kbd}`C`
+Light Position Tool                  | {kbd}`D`
 Pin to numeric bookmark              | {kbd}`1` … {kbd}`9`
 
 ### 3D scenes ###
@@ -273,6 +274,16 @@ Action                                        | Control or shortcut
 Adjust, fine precision                        | Hold {kbd}`Shift` during action
 Constrain to aspect ratio (Quad lights only)  | Hold {kbd}`Ctrl` during action
 
+### Light Position Tool ###
+
+> Note :
+> For the following controls and shortcuts, the Light Position Tool must be active.
+
+Action                                        | Control or shortcut
+----------------------------------------------|--------------------
+Set shadow pivot position                     | {kbd}`Ctrl` + {{leftClick}}
+Set shadow point                              | {kbd}`Shift` + {{leftClick}}
+
 
 ### 2D images ###
 

include/GafferSceneUI/LightPositionTool.h

@@ -0,0 +1,112 @@
+//////////////////////////////////////////////////////////////////////////
+//
+//  Copyright (c) 2023, Cinesite VFX Ltd. All rights reserved.
+//
+//  Redistribution and use in source and binary forms, with or without
+//  modification, are permitted provided that the following conditions are
+//  met:
+//
+//      * Redistributions of source code must retain the above
+//        copyright notice, this list of conditions and the following
+//        disclaimer.
+//
+//      * Redistributions in binary form must reproduce the above
+//        copyright notice, this list of conditions and the following
+//        disclaimer in the documentation and/or other materials provided with
+//        the distribution.
+//
+//      * Neither the name of John Haddon nor the names of
+//        any other contributors to this software may be used to endorse or
+//        promote products derived from this software without specific prior
+//        written permission.
+//
+//  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+//  IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+//  THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+//  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+//  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+//  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+//  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+//  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+//  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+//  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+//  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+//////////////////////////////////////////////////////////////////////////
+
+#pragma once
+
+#include "GafferSceneUI/Export.h"
+#include "GafferSceneUI/TransformTool.h"
+#include "GafferSceneUI/TypeIds.h"
+
+#include "Gaffer/ScriptNode.h"
+
+namespace GafferSceneUI
+{
+
+IE_CORE_FORWARDDECLARE( SceneView );
+
+class GAFFERSCENEUI_API LightPositionTool : public GafferSceneUI::TransformTool
+{
+
+	public :
+
+		LightPositionTool( SceneView *view, const std::string &name = defaultName<LightPositionTool>() );
+		~LightPositionTool() override;
+
+		GAFFER_NODE_DECLARE_TYPE( GafferSceneUI::LightPositionTool, LightPositionToolTypeId, TransformTool );
+
+		void position( const Imath::V3f &shadowPivot, const Imath::V3f &shadowPoint );
+
+	protected :
+
+		bool affectsHandles( const Gaffer::Plug *input ) const override;
+		void updateHandles( float rasterScale ) override;
+
+	private :
+
+		struct TranslationRotation
+		{
+
+			TranslationRotation( const Selection &selection );
+
+			void apply( const Imath::V3f &tranlation, const Imath::Eulerf &rotation );
+
+			private :
+
+				Imath::V3f updatedRotateValue( const Gaffer::V3fPlug *rotatePlug, const Imath::Eulerf &rotation, Imath::V3f *currentValue = nullptr ) const;
+
+				const Selection &m_selection;
+				Imath::M44f m_gadgetToTranslationXform;
+				Imath::M44f m_gadgetToRotationXform;
+
+				mutable std::optional<Imath::V3f> m_originalTranslation;
+				mutable std::optional<Imath::Eulerf> m_originalRotation;  // Radians
+
+		};
+
+		void selectionChanged( const TransformTool &tool );
+		void plugSet( Gaffer::Plug *plug );
+		void plugInputChanged( Gaffer::Plug *Plug );
+		void connectToViewContext();
+		void contextChanged( const IECore::InternedString &name );
+
+		bool buttonPress( const GafferUI::ButtonEvent &event );
+
+		Imath::V3f m_worldCentroid;
+		Imath::Quatf m_centroidOrientation;
+
+		std::optional<Imath::V3f> m_shadowPivot;
+		std::optional<Imath::V3f> m_shadowPoint;
+
+		Gaffer::Signals::ScopedConnection m_contextChangedConnection;
+
+		static ToolDescription<LightPositionTool, SceneView> g_toolDescription;
+		static size_t g_firstPlugIndex;
+
+};
+
+IE_CORE_DECLAREPTR( LightPositionTool )
+
+}  // namespace GafferSceneUI

include/GafferSceneUI/TypeIds.h

@@ -57,6 +57,7 @@ enum TypeId
 	HistoryPathTypeId = 110664,
 	SetPathTypeId = 110665,
 	LightToolTypeId = 110666,
+	LightPositionToolTypeId = 110667,
 
 	LastTypeId = 110700
 };

python/GafferSceneUI/LightPositionToolUI.py

@@ -0,0 +1,72 @@
+##########################################################################
+#
+#  Copyright (c) 2023, Cinesite VFX Ltd. All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are
+#  met:
+#
+#      * Redistributions of source code must retain the above
+#        copyright notice, this list of conditions and the following
+#        disclaimer.
+#
+#      * Redistributions in binary form must reproduce the above
+#        copyright notice, this list of conditions and the following
+#        disclaimer in the documentation and/or other materials provided with
+#        the distribution.
+#
+#      * Neither the name of John Haddon nor the names of
+#        any other contributors to this software may be used to endorse or
+#        promote products derived from this software without specific prior
+#        written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+#  IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+#  THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+#  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+#  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+#  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+#  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+#  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+#  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+#  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+#  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+##########################################################################
+
+import Gaffer
+import GafferUI
+import GafferSceneUI
+
+Gaffer.Metadata.registerNode(
+
+	GafferSceneUI.LightPositionTool,
+
+	"description",
+	"""
+	Tool for placing lights.
+	""",
+
+	"viewer:shortCut", "D",
+	"order", 7,
+	"tool:exclusive", True,
+
+	"nodeToolbar:bottom:type", "GafferUI.StandardNodeToolbar.bottom",
+
+	"toolbarLayout:customWidget:InteractionTipWidget:widgetType", "GafferSceneUI.LightPositionToolUI._InteractionTipWidget",
+	"toolbarLayout:customWidget:InteractionTipWidget:section", "Bottom",
+	"toolbarLayout:customWidget:InteractionTipWidget:index", -1,
+
+)
+
+class _InteractionTipWidget( GafferUI.Frame ) :
+
+	def __init__( self, tool, **kw ) :
+
+		GafferUI.Frame.__init__( self, borderWidth = 4, **kw )
+
+		with self :
+			with GafferUI.ListContainer( orientation = GafferUI.ListContainer.Orientation.Vertical, spacing = 4 ) :
+				GafferUI.Label( "Control + Left Click to place shadow pivot" )
+				GafferUI.Label( "Shift + Left Click to place shadow target" )
+				GafferUI.Label( "Deactivate tool to reset shadow and pivot points")

python/GafferSceneUI/__init__.py

@@ -190,6 +190,7 @@
 from . import RenderPassesUI
 from . import DeleteRenderPassesUI
 from . import RenderPassWedgeUI
+from . import LightPositionToolUI
 
 # then all the PathPreviewWidgets. note that the order
 # of import controls the order of display.

python/GafferSceneUITest/LightPositionToolTest.py

@@ -0,0 +1,132 @@
+##########################################################################
+#
+#  Copyright (c) 2023, Cinesite VFX Ltd. All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are
+#  met:
+#
+#      * Redistributions of source code must retain the above
+#        copyright notice, this list of conditions and the following
+#        disclaimer.
+#
+#      * Redistributions in binary form must reproduce the above
+#        copyright notice, this list of conditions and the following
+#        disclaimer in the documentation and/or other materials provided with
+#        the distribution.
+#
+#      * Neither the name of John Haddon nor the names of
+#        any other contributors to this software may be used to endorse or
+#        promote products derived from this software without specific prior
+#        written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+#  IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+#  THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+#  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+#  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+#  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+#  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+#  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+#  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+#  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+#  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+##########################################################################
+
+import unittest
+import random
+import math
+
+import imath
+
+import IECore
+
+import Gaffer
+import GafferUITest
+import GafferSceneUI
+import GafferSceneTest
+
+class LightPositionToolTest( GafferUITest.TestCase ) :
+
+	def __shadowSource( self, lightP, shadowPivot, shadowPoint ) :
+		return ( shadowPivot - shadowPoint ).normalize() * ( lightP - shadowPivot ).length() + shadowPivot
+
+	def testPosition( self ) :
+
+		random.seed( 42 )
+
+		script = Gaffer.ScriptNode()
+		script["light"] = GafferSceneTest.TestLight()
+
+		view = GafferSceneUI.SceneView()
+		view["in"].setInput( script["light"]["out"] )
+		GafferSceneUI.ContextAlgo.setSelectedPaths( view.getContext(), IECore.PathMatcher( [ "/light" ] ) )
+
+		tool = GafferSceneUI.LightPositionTool( view )
+		tool["active"].setValue( True )
+
+		for i in range( 0, 5 ) :
+			lightP = imath.V3f( random.random() * 10 - 5, random.random() * 10 - 5, random.random() * 10 - 5 )
+			shadowPivot = imath.V3f( random.random() * 10 - 5, random.random() * 10 - 5, random.random() * 10 - 5 )
+			shadowPoint = imath.V3f( random.random() * 10 - 5, random.random() * 10 - 5, random.random() * 10 - 5 )
+
+			script["light"]["transform"]["translate"].setValue( lightP )
+			tool.handlesTransform()  # Trigger `updateHandles()` to update our centroid
+
+			d0 = ( lightP - shadowPivot ).length()
+			upDir = script["light"]["transform"].matrix().multDirMatrix( imath.V3f( 0, 1, 0 ) )
+
+			tool.position( shadowPivot, shadowPoint )
+
+			p = script["light"]["transform"]["translate"].getValue()
+
+			d1 = ( p - shadowPivot ).length()
+			self.assertAlmostEqual( d0, d1, places = 4 )
+
+			desiredP = self.__shadowSource( lightP, shadowPivot, shadowPoint )
+
+			for j in range( 0, 3 ) :
+				self.assertAlmostEqual( p[j], desiredP[j], places = 4 )
+
+			desiredO = imath.M44f()
+			imath.M44f.rotationMatrixWithUpDir( desiredO, imath.V3f( 0, 0, -1 ), shadowPoint - shadowPivot, upDir )
+			rotationO = imath.V3f()
+			desiredO.extractEulerXYZ( rotationO )
+
+			o = script["light"]["transform"]["rotate"].getValue()
+
+			for j in range( 0, 3 ) :
+				self.assertAlmostEqual( o[j] % 360, math.degrees( rotationO[j] ) % 360, places = 3 )
+
+	def testUndo( self ) :
+
+		script = Gaffer.ScriptNode()
+		script["light"] = GafferSceneTest.TestLight()
+
+		view = GafferSceneUI.SceneView()
+		view["in"].setInput( script["light"]["out"] )
+		GafferSceneUI.ContextAlgo.setSelectedPaths( view.getContext(), IECore.PathMatcher( [ "/light" ] ) )
+
+		tool = GafferSceneUI.LightPositionTool( view )
+		tool["active"].setValue( True )
+
+		tool.handlesTransform()  # Trigger `updateHandles()` to update our centroid
+
+		p = imath.V3f( 0, 0, 0 )
+		shadowPivot = imath.V3f( 4, 5, 6 )
+		shadowPoint = imath.V3f( 7, 8, 9 )
+		tool.position( shadowPivot, shadowPoint )
+
+		newP = script["light"]["transform"]["translate"].getValue()
+		shadowSource = self.__shadowSource( p, shadowPivot, shadowPoint )
+		for i in range( 0, 3 ) :
+			self.assertAlmostEqual( newP[i], shadowSource[i], places = 4 )
+
+		script.undo()
+
+		self.assertEqual( script["light"]["transform"]["translate"].getValue(), imath.V3f( 0, 0, 0 ) )
+
+
+if __name__ == "__main__" :
+	unittest.main()

python/GafferSceneUITest/__init__.py

@@ -59,6 +59,7 @@
 from .SetMembershipInspectorTest import SetMembershipInspectorTest
 from .SetEditorTest import SetEditorTest
 from .LightToolTest import LightToolTest
+from .LightPositionToolTest import LightPositionToolTest
 
 if __name__ == "__main__":
 	unittest.main()

python/GafferUI/_StyleSheet.py

@@ -1492,6 +1492,7 @@ def styleColor( key ) :
 	#gafferColorInspector,
 	*[gafferClass="GafferSceneUI.TransformToolUI._SelectionWidget"],
 	*[gafferClass="GafferSceneUI.CropWindowToolUI._StatusWidget"],
+	*[gafferClass="GafferSceneUI.LightPositionToolUI._InteractionTipWidget"],
 	*[gafferClass="GafferUI.EditScopeUI.EditScopePlugValueWidget"] > QFrame,
 	*[gafferClass="GafferSceneUI.InteractiveRenderUI._ViewRenderControlUI"] > QFrame,
 	*[gafferClass="GafferSceneUI._SceneViewInspector"] > QFrame

resources/graphics.py

@@ -195,6 +195,7 @@
 				'gafferSceneUIScaleTool',
 				'gafferSceneUITranslateTool',
 				'gafferSceneUILightTool',
+				'gafferSceneUILightPositionTool',
 			]
 
 		},