GafferUI : Fix use of Gaffer Widget mouse event positions

Fixes some cursor offsets introduced since we fixed the coordinates
reported in `GafferUI.ButtonEvent` in #4053.

python/GafferUI/PathListingWidget.py

@@ -172,12 +172,12 @@ def scrollToPath( self, path ) :
 	# exists at that position.
 	def pathAt( self, position ) :
 
-		position = self._qtWidget().viewport().mapFrom(
+		point = self._qtWidget().viewport().mapFrom(
 			self._qtWidget(),
 			QtCore.QPoint( position.x, position.y )
 		)
 
-		index = self._qtWidget().indexAt( position )
+		index = self._qtWidget().indexAt( point )
 		if not index.isValid() :
 			return None
 
@@ -514,7 +514,12 @@ def __buttonPress( self, widget, event ) :
 			# This is further complicated by the fact that the button presses we simulate for Qt
 			# will end up back in this function, so we have to be careful to ignore those.
 
-			index = self._qtWidget().indexAt( QtCore.QPoint( event.line.p0.x, event.line.p0.y ) )
+			point = self._qtWidget().viewport().mapFrom(
+				self._qtWidget(),
+				QtCore.QPoint( event.line.p0.x, event.line.p0.y )
+			)
+			index = self._qtWidget().indexAt( point )
+
 			if self._qtWidget().selectionModel().isSelected( index ) :
 				# case 1 : existing selection.
 				self.__borrowedButtonPress = event
@@ -551,7 +556,11 @@ def __dragBegin( self, widget, event ) :
 		self.__borrowedButtonPress = None
 
 		# nothing to drag if there's no valid list entry under the pointer
-		index = self._qtWidget().indexAt( QtCore.QPoint( event.line.p0.x, event.line.p0.y ) )
+		point = self._qtWidget().viewport().mapFrom(
+			self._qtWidget(),
+			QtCore.QPoint( event.line.p0.x, event.line.p0.y )
+		)
+		index = self._qtWidget().indexAt( point )
 		if not index.isValid() :
 			return None
 
@@ -568,9 +577,14 @@ def __dragEnd( self, widget, event ) :
 
 	def __emitButtonPress( self, event ) :
 
+		point = self._qtWidget().viewport().mapFrom(
+			self._qtWidget(),
+			QtCore.QPoint( event.line.p0.x, event.line.p0.y )
+		)
+
 		qEvent = QtGui.QMouseEvent(
 			QtCore.QEvent.MouseButtonPress,
-			QtCore.QPoint( event.line.p0.x, event.line.p0.y ),
+			point,
 			QtCore.Qt.LeftButton,
 			QtCore.Qt.LeftButton,
 			QtCore.Qt.NoModifier

python/GafferUI/SpreadsheetUI/_PlugTableView.py

@@ -146,7 +146,11 @@ def __init__( self, selectionModel, mode, **kw ) :
 
 	def plugAt( self, position ) :
 
-		index = self._qtWidget().indexAt( QtCore.QPoint( position.x, position.y ) )
+		point = self._qtWidget().viewport().mapFrom(
+			self._qtWidget(),
+			QtCore.QPoint( position.x, position.y )
+		)
+		index = self._qtWidget().indexAt( point )
 		return self._qtWidget().model().plugForIndex( index )
 
 	def selectedPlugs( self ) :
@@ -357,7 +361,11 @@ def __buttonPress( self, widget, event ) :
 		if event.buttons != event.Buttons.Right :
 			return False
 
-		index = self._qtWidget().indexAt( QtCore.QPoint( event.line.p0.x, event.line.p0.y ) )
+		point = self._qtWidget().viewport().mapFrom(
+			self._qtWidget(),
+			QtCore.QPoint( event.line.p0.x, event.line.p0.y )
+		)
+		index = self._qtWidget().indexAt( point )
 
 		# Disabled items won't show up in the selection model
 		if not index.flags() & QtCore.Qt.ItemIsEnabled :
@@ -417,7 +425,11 @@ def __buttonDoubleClick( self, widget, event ) :
 		#  - Presets: Return/Double click displays the popup menu, requires right-click
 		#    to display the edit window.
 
-		index = self._qtWidget().indexAt( QtCore.QPoint( event.line.p0.x, event.line.p0.y ) )
+		point = self._qtWidget().viewport().mapFrom(
+			self._qtWidget(),
+			QtCore.QPoint( event.line.p0.x, event.line.p0.y )
+		)
+		index = self._qtWidget().indexAt( point )
 
 		if not index.flags() & QtCore.Qt.ItemIsEnabled :
 			return True
@@ -504,7 +516,8 @@ def __headerButtonPress( self, header, event ) :
 		if event.buttons != event.Buttons.Right :
 			return False
 
-		cellPlug = self.plugAt( event.line.p0 )
+		column = self._qtWidget().columnAt( event.line.p0.x )
+		cellPlug = self._qtWidget().model().plugForIndex( self._qtWidget().model().index( 0, column ) )
 		assert( cellPlug.ancestor( Gaffer.Spreadsheet.RowPlug ) == cellPlug.ancestor( Gaffer.Spreadsheet.RowsPlug ).defaultRow() )
 
 		menuDefinition = IECore.MenuDefinition()

python/GafferUI/VectorDataWidget.py

@@ -367,7 +367,8 @@ def getDragPointer( self ) :
 	# data returned by getData().
 	def indexAt( self, position ) :
 
-		index = self.__tableView.indexAt( QtCore.QPoint( position[0], position[1] ) )
+		point = self.__tableView.viewport().mapFrom( self.__tableView, QtCore.QPoint( position[0], position[1] ) )
+		index = self.__tableView.indexAt( point )
 		return ( index.column(), index.row() )
 
 	## Returns a list of ( columnIndex, rowIndex ) for the currently
@@ -662,7 +663,11 @@ def __buttonPress( self, widget, event ) :
 			# This is further complicated by the fact that the button presses we simulate for Qt
 			# will end up back in this function, so we have to be careful to ignore those.
 
-			index = self.__tableView.indexAt( QtCore.QPoint( event.line.p0.x, event.line.p0.y ) )
+			point = self.__tableView.viewport().mapFrom(
+				self.__tableView,
+				QtCore.QPoint( event.line.p0.x, event.line.p0.y )
+			)
+			index = self.__tableView.indexAt( point )
 			if self.__tableView.selectionModel().isSelected( index ) :
 				# case 1 : existing selection.
 				self.__borrowedButtonPress = event
@@ -714,9 +719,14 @@ def __dragEnd( self, widget, event ) :
 
 	def __emitButtonPress( self, event ) :
 
+		point = self.__tableView.viewport().mapFrom(
+			self.__tableView,
+			QtCore.QPoint( event.line.p0.x, event.line.p0.y )
+		)
+
 		qEvent = QtGui.QMouseEvent(
 			QtCore.QEvent.MouseButtonPress,
-			QtCore.QPoint( event.line.p0.x, event.line.p0.y ),
+			point,
 			QtCore.Qt.LeftButton,
 			QtCore.Qt.LeftButton,
 			QtCore.Qt.NoModifier