|Message: A track stuck between two volumes||Not Logged In (login)|
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Recently my colleague experienced a geometry related problem.
He was doing material scan, but found that a track stuck at a certain position between two volumes, which was hanging his job. The step length of the track was very small at that area, from 0 to 1e-13, and it was doing infinite looping between two volumes.
He solved the problem by inserting a go-around in his own code. However, we wonder if this is just one incident or a glimpse of a more general problem. If it is the latter case, the Geant4 code may need a tolerance for the zero step length. For example, the line
fLastStepWasZero = (Step==0.0);
in G4Navigataor.cc could have a tolerance logic instead.
Has anyone experienced a similar problem? I would be happy to listen to your opinions.