add docstrings

Wrappers/Python/ccpi/viewer/CILViewer2D.py

@@ -1470,7 +1470,11 @@ def installRectilinearWipePipeline(self):
         self.AddActor(wipeSlice, WIPE_ACTOR)
 
     def installSliceSliderWidgetPipeline(self):
-
+        '''Create the pipeline for the slice slider widget
+        
+        The slider widget and representation are created if not already present.
+        Currently the slider widget enabled flag is not used.
+        '''
         if self.sliderWidget is not None:
             # reset the values to the appropriate ones of the new loaded image
             self.sliderCallback.update_orientation(self.style, 'reset')
@@ -1490,8 +1494,10 @@ def installSliceSliderWidgetPipeline(self):
         cb = SliderCallback(self, sw)
 
         # Add interaction observers
+        # propagate events from the slider to the viewer
         sw.AddObserver(vtk.vtkCommand.InteractionEvent, cb)
 
+        # propagate events from the viewer to the slider
         self.style.AddObserver("MouseWheelForwardEvent", cb.update_from_viewer, 0.9 )
         self.style.AddObserver("MouseWheelBackwardEvent", cb.update_from_viewer, 0.9 )
         self.style.AddObserver("CharEvent", cb.update_orientation, 0.9 )
@@ -1502,10 +1508,9 @@ def installSliceSliderWidgetPipeline(self):
         # save references
         self.sliderWidget = sw
         self.sliderCallback = cb
-        # self.sliderMinMaxLabels = (mtw, Mtw)
-
-    def uninstallSliderWidget(self):
 
+    def uninstallSliderWidget(self):
+        '''remove the slider widget from the viewer'''
         if self.sliderWidget is not None:
             sr = self.sliderWidget.GetRepresentation()
             if sr is not None:

Wrappers/Python/ccpi/viewer/widgets/slider.py

@@ -17,7 +17,7 @@ class SliceSliderRepresentation(vtk.vtkSliderRepresentation2D):
 
     def __init__(self, orientation='horizontal', offset=0.12):
         self.tube_width = 0.004
-        self.slider_length = 0.025
+        self.slider_length = 0.015
         self.slider_width = 0.015
         self.end_cap_length = 0.008
         self.end_cap_width = 0.02
@@ -72,7 +72,7 @@ def __init__(self, orientation='horizontal', offset=0.12):
 class SliderCallback:
     '''
     Class to propagate the effects of interaction between the slider widget and the viewer 
-    the slider is embedded into.
+    the slider is embedded into, and viceversa.
     
     Parameters:
     -----------
@@ -85,13 +85,26 @@ def __init__(self, viewer, slider_widget):
         self.slider_widget = slider_widget
 
     def __call__(self, caller, ev):
+        '''Update the slice displayed by the viewer when the slider is moved
+        
+        Parameters:
+        -----------
+        - caller, the slider widget
+        - ev, the event that triggered the update
+        '''
         slider_widget = caller
         value = slider_widget.GetRepresentation().GetValue()
         self.viewer.displaySlice(int(value))
-        self.update_label(slider_widget, value)
+        self.update_label(value)
 
-    def update_label(self, slider_widget, value):
-        rep = slider_widget.GetRepresentation()
+    def update_label(self, value):
+        '''Update the text label on the slider. This is called by update_from_viewer
+        
+        Parameters:
+        -----------
+        - value, the value to be displayed on text label the slider
+        '''
+        rep = self.slider_widget.GetRepresentation()
         maxval = rep.GetMaximumValue()
         txt = "Slice {}/{}".format(int(value), int(maxval))
         rep.SetLabelFormat(txt)
@@ -108,7 +121,7 @@ def update_from_viewer(self, caller, ev):
         logger.info(f"Updating for event {ev}")
         value = caller.GetActiveSlice()
         self.slider_widget.GetRepresentation().SetValue(value)
-        self.update_label(self.slider_widget, value)
+        self.update_label(value)
         caller.GetRenderWindow().Render()
 
     def update_orientation(self, caller, ev):