Use GDML constants in ROOT script

[Zhiyhep]

Dear ROOT Experts:

I am using GDML to build detector geometry in my simulation project. And within the GDML file, I define some constants to specify volume dimensions and distances between them, e.g.

<define>
        <constant name="Chamber_Size_X" value="520"/>
        <constant name="Chamber_Size_Y" value="520"/>
        <constant name="Chamber_Size_Z" value="15"/>

        <constant name="ObjectAreaWidth" value="300"/>
        <constant name="Detector_Offset" value="100"/>
        <constant name="Plate_Size_X" value="500"/>
        <constant name="Plate_Size_Y" value="500"/>
        <constant name="Plate_Size_Z" value="2.5"/>
</define> 

And I want to use these constants in my root script. In case i change the constant values, I want the ROOT scripts to trace the change automatically.

Is there any way to do so ?

Best,
Zhi Yu

[ksmith]

Have you verified that the TGeoManager suports the constant tag? It appears that the quantity tag is not supported at the moment:

It appears that TGeoManager does not support the quantity tag. ROOT: root [0] TGeoManager::Import("root-test.gdml") Info in <TGeoManager::Import>: Reading geometry from file: root-test.gdml Info in <TGeoManager::TGeoManager>: Geometry GDMLImport, Geometry imported from GDML created Error: Unsupported GDML Tag Used :quantity. Please Check Geometry/Schema. Error: Unsupported GDML Tag Used :quantity. Please Check Geometry/Schema. Medium: G4_Al, Not Yet Defined! Info in <TGeoManager::SetTopVolume>…

[Zhiyhep]

Hi,

Sorry i didn’t upload the full gdml file, please refer to the attachment.

TGeoManager::Import(“Muon_Setup.gdml”) works fine on my computer.

Best,
Zhi Yu

Geometry.tar.gz (3.5 KB)