BUG: Fix disappearing earth on pan.
BUG: Fix disappearing earth on pan.

sankhesh/VTK,sumedhasingla/VTK,spthaolt/VTK,msmolens/VTK,Wuteyan/VTK,demarle/VTK,daviddoria/PointGraphsPhase1,spthaolt/VTK,keithroe/vtkoptix,hendradarwin/VTK,johnkit/vtk-dev,aashish24/VTK-old,spthaolt/VTK,arnaudgelas/VTK,spthaolt/VTK,sankhesh/VTK,daviddoria/PointGraphsPhase1,berendkleinhaneveld/VTK,mspark93/VTK,demarle/VTK,collects/VTK,sumedhasingla/VTK,SimVascular/VTK,candy7393/VTK,naucoin/VTKSlicerWidgets,daviddoria/PointGraphsPhase1,spthaolt/VTK,jeffbaumes/jeffbaumes-vtk,SimVascular/VTK,mspark93/VTK,ashray/VTK-EVM,jeffbaumes/jeffbaumes-vtk,mspark93/VTK,ashray/VTK-EVM,hendradarwin/VTK,candy7393/VTK,Wuteyan/VTK,johnkit/vtk-dev,jmerkow/VTK,spthaolt/VTK,johnkit/vtk-dev,berendkleinhaneveld/VTK,daviddoria/PointGraphsPhase1,Wuteyan/VTK,johnkit/vtk-dev,mspark93/VTK,SimVascular/VTK,mspark93/VTK,jeffbaumes/jeffbaumes-vtk,sumedhasingla/VTK,jmerkow/VTK,aashish24/VTK-old,candy7393/VTK,cjh1/VTK,johnkit/vtk-dev,cjh1/VTK,daviddoria/PointGraphsPhase1,SimVascular/VTK,johnkit/vtk-dev,arnaudgelas/VTK,ashray/VTK-EVM,arnaudgelas/VTK,collects/VTK,cjh1/VTK,msmolens/VTK,johnkit/vtk-dev,hendradarwin/VTK,candy7393/VTK,mspark93/VTK,sumedhasingla/VTK,jeffbaumes/jeffbaumes-vtk,naucoin/VTKSlicerWidgets,berendkleinhaneveld/VTK,gram526/VTK,aashish24/VTK-old,msmolens/VTK,collects/VTK,sankhesh/VTK,SimVascular/VTK,keithroe/vtkoptix,gram526/VTK,msmolens/VTK,gram526/VTK,spthaolt/VTK,SimVascular/VTK,Wuteyan/VTK,keithroe/vtkoptix,sankhesh/VTK,hendradarwin/VTK,demarle/VTK,mspark93/VTK,collects/VTK,daviddoria/PointGraphsPhase1,sankhesh/VTK,berendkleinhaneveld/VTK,hendradarwin/VTK,naucoin/VTKSlicerWidgets,gram526/VTK,biddisco/VTK,hendradarwin/VTK,berendkleinhaneveld/VTK,collects/VTK,jmerkow/VTK,biddisco/VTK,demarle/VTK,biddisco/VTK,sankhesh/VTK,jmerkow/VTK,jmerkow/VTK,msmolens/VTK,demarle/VTK,berendkleinhaneveld/VTK,keithroe/vtkoptix,naucoin/VTKSlicerWidgets,biddisco/VTK,candy7393/VTK,keithroe/vtkoptix,cjh1/VTK,ashray/VTK-EVM,demarle/VTK,gram526/VTK,mspark93/VTK,sankhesh/VTK,SimVascular/VTK,jmerkow/VTK,msmolens/VTK,ashray/VTK-EVM,biddisco/VTK,ashray/VTK-EVM,naucoin/VTKSlicerWidgets,jeffbaumes/jeffbaumes-vtk,candy7393/VTK,Wuteyan/VTK,gram526/VTK,arnaudgelas/VTK,jmerkow/VTK,Wuteyan/VTK,biddisco/VTK,Wuteyan/VTK,demarle/VTK,sumedhasingla/VTK,arnaudgelas/VTK,naucoin/VTKSlicerWidgets,msmolens/VTK,SimVascular/VTK,arnaudgelas/VTK,cjh1/VTK,hendradarwin/VTK,aashish24/VTK-old,collects/VTK,sumedhasingla/VTK,candy7393/VTK,gram526/VTK,demarle/VTK,berendkleinhaneveld/VTK,sumedhasingla/VTK,biddisco/VTK,keithroe/vtkoptix,cjh1/VTK,keithroe/vtkoptix,aashish24/VTK-old,sumedhasingla/VTK,candy7393/VTK,gram526/VTK,jeffbaumes/jeffbaumes-vtk,keithroe/vtkoptix,aashish24/VTK-old,msmolens/VTK,sankhesh/VTK,ashray/VTK-EVM,ashray/VTK-EVM,jmerkow/VTK