Use LERP interpolation for infinitesimally small angles instead of SLERP
Use LERP interpolation for infinitesimally small angles instead of SLERP

To avoid division by zero, perform a linear interpolation (LERP), if our
quarternions are nearly in the same direction, otherwise resort
to spherical linear interpolation. In the limiting case (for small
angles), SLERP is equivalent to LERP.

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