1. Geometry checking tools
G.Cosmo - Geometry checking tools
October 9th, 2002
Geometry checking tools
Gabriele Cosmo (CERN/IT-API)
Geant4 delta-review

2. G.Cosmo - Geometry checking tools
October 9th, 2002
Outline
Addressing recommendation #3.6:
“ The GEANT4 team should provide a basic set of tools to validate
complicated detector geometries. These tools should be available
to users not only as a set of C++ classes that the end user can
access from his own application but also as part of an interactive
geometry display package. A minimal set of requirements for
interactive capabilities are those provided by interactive GEANT3 ”
An interactive graphical tool for debugging overlapping geometries is provided since 1998
Additional run-time commands for fast and effective debugging have been made available since release 4.0 and extended in release 4.1
A new interactive tool for geometry debugging is available in release 4.1
DTREE commands available since release 4.0
October 9th, 2002
Geant4 delta-review - G.Cosmo, Geometry checking tools
Geant4 delta-review

3. G.Cosmo - Geometry checking tools
October 9th, 2002
DAVID Graphical Tool
Released in 1998
Allows for precise rendering of complex geometries and possible imperfections
Generates precise debug information to identify overlapping elements
Can be run as a stand-alone application
October 9th, 2002
Geant4 delta-review - G.Cosmo, Geometry checking tools
Geant4 delta-review

4. Run-time debugging commands
Available since release 4.0, as contribution of the BaBar collaboration
Used in BaBar for the verification of the detailed geometry description of the BaBar detector
Built-in commands to activate verification tests on the user geometry setup
Adopts technique of intersecting solids with linear trajectories
Several pattern algorithms available (single line, recursive grid, cylinder, …)
Precise output produced
Excellent coverage if combined with DAVID
October 9th, 2002
Geant4 delta-review - G.Cosmo, Geometry checking tools

5. Geant4 delta-review - G.Cosmo, Geometry checking tools
OLAP tool
Available in release 4.1, contribution of the CMS collaboration
Uses tracking of neutral particles to verify boundary crossing in opposite directions
Stand-alone batch application
Can be combined with a graphical environment and GUI (ex. Qt library)
Integrated in the CMS Iguana Framework
October 9th, 2002
Geant4 delta-review - G.Cosmo, Geometry checking tools

6. Geant4 delta-review - G.Cosmo, Geometry checking tools
OLAP tool
October 9th, 2002
Geant4 delta-review - G.Cosmo, Geometry checking tools

7. Visualizing detector geometry tree
Built-in commands defined since release 4.0 to display the hierarchical geometry tree
As simple ASCII text structure
Graphical through GUI (combined with GAG)
As XML exportable format
Implemented in the visualization module
As an additional graphics driver
G3 DTREE capabilities provided and more
October 9th, 2002
Geant4 delta-review - G.Cosmo, Geometry checking tools

8. Geant4 delta-review - G.Cosmo, Geometry checking tools
October 9th, 2002
Geant4 delta-review - G.Cosmo, Geometry checking tools

9. Geant4 delta-review - G.Cosmo, Geometry checking tools
Conclusions
Interactive graphical tool DAVID for debugging overlapping geometries provided since the first production release in 1998 (defined UR)
BaBar contribution in release 4.0: built-in run-time commands based on linear intersection technique
Set of commands extended in release 4.1
CMS contribution in release 4.1: OLAP tool for tracking-based debugging
DTREE functionality and commands available since release 4.0
Future evolutions:
Extend OLAP tool with integrated GUI Qt-based
October 9th, 2002
Geant4 delta-review - G.Cosmo, Geometry checking tools