Fix GetShiftedLevelZeroIndex method
Fix GetShiftedLevelZeroIndex method
Change GetShiftedLevelZeroIndex method signature to support negative shifts
Extend 2D HTG case beyond the classic XY
Extend vtkRandomHyperTreeGridSource to 2D HTG case beyond the classic XY.
Extend the vtkRandomHyperTreeGridSource test to ensure the sustainability of this fix
Edited by Jacques-Bernard Lekien