Some improvements to gradient opacity
Some improvements to gradient opacity

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