diff --git a/tools/octree_viewer.cpp b/tools/octree_viewer.cpp
index 4e6a9e97f5c..0aea165b68f 100644
--- a/tools/octree_viewer.cpp
+++ b/tools/octree_viewer.cpp
@@ -287,16 +287,16 @@ class OctreeViewer
       wk_cubeSource->Update ();
 
 #if VTK_MAJOR_VERSION < 6
-      appendFilter->AddInput(wk_cubeSource->GetOutput ());
+      appendFilter->AddInput (wk_cubeSource->GetOutput ());
 #else
-      appendFilter->AddInputData(wk_cubeSource->GetOutput ());
+      appendFilter->AddInputData (wk_cubeSource->GetOutput ());
 #endif
     }
 
     // Remove any duplicate points
     vtkSmartPointer<vtkCleanPolyData> cleanFilter = vtkSmartPointer<vtkCleanPolyData>::New ();
 
-    cleanFilter->SetInputConnection(appendFilter->GetOutputPort ());
+    cleanFilter->SetInputConnection (appendFilter->GetOutputPort ());
     cleanFilter->Update ();
 
     //Create a mapper and actor
@@ -346,7 +346,7 @@ class OctreeViewer
     for (tree_it = octree.begin(depth); tree_it!=tree_it_end; ++tree_it)
     {
       if (tree_it.getCurrentOctreeDepth () != depth)
-        continue ;
+        continue;
 
       Eigen::Vector3f voxel_min, voxel_max;
       octree.getVoxelBounds(tree_it, voxel_min, voxel_max);