Problem 91

Summary:	Infinite loop in tracking geantino in a simple tube segment
Product:	Geant4	Reporter:	Ivana.Hrivnacova
Component:	geometry/volumes	Assignee:	John Apostolakis <John.Apostolakis>
Status:	CLOSED DUPLICATE
Severity:	critical
Priority:	P2
Version:	1.0
Hardware:	PC
OS:	Linux
URL:	/afs/cern.ch/user/g/gcosmo/public/bug91.tar.gz

Description Ivana.Hrivnacova 2000-04-28 02:03:24 CEST

We are getting infinite loop when geantino is
tracked in a simple tube segment (G4Tubs with SPhi<0).

The concrete examples (modified N02 detector construction
class + test macro and test output) is provided in:
/afs/cern.ch/user/i/ivana/public/g4looping

Comment 1 Gabriele Cosmo 2000-05-03 05:47:59 CEST

I verified that the loop happens in G4Navigator (G4NormalNavigation) as the
step-length is always set to zero. I modified the simple test-case based on
exampleN02 and made it available in my public AFS area:
   ~gcosmo/public/bug91.tar.gz
I verified that the problem persists in reference tag "geant4-01-01-ref-03".

Comment 2 John Apostolakis 2000-05-16 11:38:59 CEST

*** This bug has been marked as a duplicate of 76 ***

Comment 3 Vladimir.Grichine 2000-05-17 12:01:59 CEST

Bug fixed in G4Tubs::DistanceToOut

Comment 4 John Apostolakis 2000-05-18 12:22:59 CEST

Confirmed that the program now works - does not loop - when using the new
fix in the Tubs.