Added work-around for fact that VTK does not invoke interactionevent at mousewheel.
Added work-around for fact that VTK does not invoke interactionevent
at mousewheel.

chrisidefix/devide,nagyistoce/devide,fvpolpeta/devide,zhangfangyan/devide,ivoflipse/devide,zhangfangyan/devide,fvpolpeta/devide,nagyistoce/devide,chrisidefix/devide,ivoflipse/devide