ENH: fixes to cave rendering
ENH: fixes to cave rendering

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