More legible label size

Change-Id: Iad60e890ccda1231be0f63c8e73ead093fb5de22

Hybrid/Testing/Cxx/TestPolarAxes.cxx

@@ -88,7 +88,7 @@ int TestPolarAxes( int argc, char * argv [] )
   polaxes->SetCamera( renderer->GetActiveCamera() );
   polaxes->SetRadialLabelFormat( "%6.1f" );
   polaxes->GetRadialAxesProperty()->SetColor( .0, .0, .9 );
-  polaxes->SetScreenSize( 15.0 );
+  polaxes->SetScreenSize( 12.0 );
 
   vtkNew<vtkRenderWindow> renWin;
   renWin->SetMultiSamples( 0 );

Hybrid/vtkPolarAxesActor.cxx

@@ -451,14 +451,17 @@ void vtkPolarAxesActor::BuildAxes( vtkViewport *viewport )
     axis->SetRange( 0., this->MaximumRadius );
     axis->SetMajorTickSize( .02 * this->MaximumRadius );
 
-    // Set axis title
-    vtksys_ios::ostringstream thetaStream;
-    thetaStream << theta;
-    if ( this->RadialUnits )
+    // Set axis title (except for polar axis to avoid cluttering)
+    if ( i )
       {
-      thetaStream << " deg.";
+      vtksys_ios::ostringstream thetaStream;
+      thetaStream << theta;
+      if ( this->RadialUnits )
+        {
+        thetaStream << " deg.";
+        }
+      axis->SetTitle( thetaStream.str().c_str() );
       }
-    axis->SetTitle( thetaStream.str().c_str() );
     }
 
   this->BuildPolarAxisTicks( o[0] );