Better coding style; format; documentation; for 2D mode

Change-Id: I795dc3e68ac8d60e1658c5f852b3802ea00f9ac3

Hybrid/vtkCubeAxesActor.cxx

@@ -290,33 +290,28 @@ void vtkCubeAxesActor::SetUse2DMode( int val )
     this->YAxes[i]->SetUse2DMode( val );
     this->ZAxes[i]->SetUse2DMode( val );
     }
-  if( val == 0 )
+  if( ! val )
     {
-    this->SetZAxisVisibility(1);
+    this->SetZAxisVisibility( 1 );
     }
   else
     {
-    this->SetZAxisVisibility(0);
+    this->SetZAxisVisibility( 0 );
     }
 }
 
-//! return 1 if textactor is used
 int vtkCubeAxesActor::GetUse2DMode()
 {
-  // we assume that all axes have the same value ...
+  // It is assumed that all axes have the same value
   return this->XAxes[0]->GetUse2DMode();
 }
 
-/*! for 2D axis only : during the next render, the axis positions have to be save for later use.
-  \param val : the new state
-  \note 
-  \li val = 0 : no need to save position (3D axis)
-  \li val = 1 : positions have to be saved during the next render pass
-  \li val = 2 : positions are saved -> used them
-                
-*/
 void vtkCubeAxesActor::SetSaveTitlePosition( int val )
 {
+  // For 2D mode only : 
+  //   val = 0: no need to save position (3D axis)
+  //   val = 1: positions have to be saved during the next render pass
+  //   val = 2: positions are saved -> use them
   for( int i=0 ; i < 4 ; ++i )
     {
     this->XAxes[i]->SetSaveTitlePosition( val );

Hybrid/vtkCubeAxesActor.h

@@ -366,11 +366,14 @@ public:
 
   void SetLabelScaling(bool, int, int, int);
 
-  //! use textactor if val = 1 (2D) instead of follower (3D - val = 0) for title 
+  // Description:
+  // Get/Set 2D mode
+  // NB: Use vtkTextActor for titles in 2D instead of vtkAxisFollower
   void SetUse2DMode( int val );
-  //! return 1 if textactor is used
   int GetUse2DMode();
-  //! for 2D axis only : during the next render, the axis positions have to be save for later use.
+
+  // Description:
+  // For 2D mode only: save axis title positions for later use
   void SetSaveTitlePosition( int val );
       
 protected: