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Geant4 Version: 11.10
Operating System: Windows
Compiler/Version: VC 2019
CMake Version: 3.16
I am new to the forum. I tried to add one line code G4RunManager::GetRunManager()->ReinitializeGeometry(); in the B2a example like the following
void DetectorConstruction::SetTargetMaterial(G4String materialName)
{
……
G4RunManager::GetRunManager()->ReinitializeGeometry();
}
I understand that it is not necessarily to reinitialize geometry when I changed the material of the target. But just for illustration purpose, I chose this example and put this line in this function.
After that I built and ran the B2a program in the Qt interface. In the command line I typed the following command
/B2/det/setTargetMaterial G4_Pb
/run/beamOn 1
Then I got the exception error
-------- EEEE ------- G4Exception-START -------- EEEE -------
*** G4Exception : GeomMgt0003
issued by : G4GeometryManager::SetMaximumExtent()
Extent can be set only BEFORE creating any geometry object!
*** Fatal Exception *** core dump ***
**** Track information is not available at this moment
**** Step information is not available at this moment
-------- EEEE -------- G4Exception-END --------- EEEE ------
I thought that something might be wrong in the function G4VPhysicalVolume* DetectorConstruction::DefineVolumes(). So, I commented out the line
G4GeometryManager::GetInstance()->SetWorldMaximumExtent(worldLength);
as follows.
G4VPhysicalVolume* DetectorConstruction::DefineVolumes()
{
……
// G4GeometryManager::GetInstance()->SetWorldMaximumExtent(worldLength);
……
}
I rebuilt and rerun the code and typed the same command in the command window
/B2/det/setTargetMaterial G4_Pb
/run/beamOn 1
then I got the exception
-------- WWWW ------- G4Exception-START -------- WWWW -------
*** G4Exception : DET1010
issued by : G4SDStructure::AddNewDetector()
TrackerChamberSD had already been stored in /. Object pointer is overwritten.
It’s users’ responsibility to delete the old sensitive detector object.
*** This is just a warning message. ***
-------- WWWW -------- G4Exception-END --------- WWWW -------
I think this problem might be caused by the reinitialization of the geometry and the sensitive detector. I googled the problem. But it seems that I did not get any answer about the exception. Can anyone give me some idea on this problem? Thanks.