Re: Reading in TGeo objects from file, using geomRootToGeant4 and getting "No elements defined"

Hi Brett,

I am not able to reproduce the problem.
Can you limit your geometry to just a few materials and volumes, export it in a Root file and test it within one VMC example where you replace the ConctructGeometry function with:

   TGeoManager::Import("geometry.root");    gMC->SetRootGeometry();
Send me then your code used for building geometry and your geometry Root file.
Also let me know your versions of Root, VGM and Geant4 VMC.

Best regards,

Ivana

On 05/02/2012 09:58 PM, Brett Viren wrote:
> Hi VMCers,
>
> I'm trying to put together a VMC application by following the Ex06 that
> comes with geant4_vmc. I'm having trouble using the "geomRootToGeant4"
> option to TG4RunConfiguration. If I use "geomRoot" then the
> initialization seems to go okay. The specific error I get is:
>
> Converting Root geometry to Geant4 via VGM ...
> Geant4GM::Material::Material:
> No elements defined.*** Error: Aborting execution ***
>
> There are two things I do differently from Ex06 that may be at fault.
> Please let me know if either is "bad".
>
> First, I'm building the geometry separate from my VMC app. I populate a
> TGeoManager and then call it's Export() method to save itself to a ROOT
> file. In the VMC app I then call Import() on the file. I've browsed
> this file and plain-ROOT seems to be happy with it. My VMC app's
> ConstructGeometry() method is then mostly empty except for the call to:
>
> gMC->SetRootGeometry();
>
> Second, when I create the geometry, instead of creating TGeoElement
> objects via "new" I get them by calling TGeoElementTable::FindElement()
> on the element table which I get from the TGeoManager.
>
> Are there any hints of wrong doing from this information?
>
> -Brett.
>
>

-- 
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e-mail:  Ivana.Hrivnacova_at_cern.ch
address: Institut de Physique Nucléaire, 91406 Orsay, France
phone:   +33 169156594
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