Created attachment 589 [details]
Dose distribution on 10.05.p01 using SetRegularStructureId(1) and kXAxis for parameterisation

We notice strange behavior in the dose distribution on a voxelized patient geometry after upgrading from 10.02.p02.


We have our patient geometry in a real world and have a (brachytherapy) source in the parallel mass world.
For our test we expect to see an isotropic dose distribution. Voxel parameterisation is done using:

... G4PVParameterised *phantom_phys = new G4PVParameterised("phantom_phys_real", phantomVoxel_log, PatientRealBoxLV, kXAxis, param->GetNoVoxel(), param); 
... phantom_phys->SetRegularStructureId(1);


In version 4.10.02.p02, this gives us the expected dose distribution.
In versions 4.10.02.p03 to 4.10.05.p01 (most recent version of geant4 at the time of this ticket), the distribution is not correct (see attachment).


Two ways that seem to remedy the issue (on 10.05.p01):
 1) Remove SetRegularStructureId and change kXAxis to kUndefined. However this is slower and seems to eat up memory. 

 2) Rolling back source/geometry/navigation/src/G4PhantomParameterisation.cc to what it was in 10.02.p02 remedies the problem on newer versions of Geant4.


Thank you,
Marc Morcos