---
name: "g2rootold"
section: "1"
platform: "linux"
package: "root-plugin-hbook"
version: "5.18.00-2.3~lenny1"
release: "Debian 5.0 (Lenny)"
platforms: ["linux"]
url: "https://new.carta.tech/g2rootold"
---

# g2rootold(1)

convert GEANT geomtry files to ROOT files

## NAME

g2rootold - convert GEANT geomtry files to ROOT files

## SYNOPSIS

**g2rootoldd** *\[-f map\_name\] geant\_name macro\_name*

## DESCRIPTION

You can convert a  **GEANT** (see  *http://wwwinfo.cern.ch/asd/geant/index.html* fore more on  **GEANT**) geometry to  **ROOT** geometry with the following steps

- 1

  Run the interactive version of  **GEANT** and produce a Zebra RZ file  *detector.geom*, by typing the command:

  Geant \> rz/file 21 *detector.geom* on

- 2

  Run the  **g2rootold** program to convert the Zebra RZ file into a  **ROOT** macro  *detector.C:*

  g2rootold *detector.geom* *detector.C*

- 3

  Run the following  **ROOT** session;

  ```
  root [1] .x detector.C
  root [2] detector.Draw()
  root [3] c1.x3d()   // (this invokes the 3-d Root viewver)
  root [4] TFile f("detector.root","NEW") //open a new root file
  root [5] detector.Write() //Write the geometry structure
  root [6] f.Write()
  ```

  Note that the  *TNode* structure currently in  **ROOT** was not designed as a replacement for a true geometry package. The idea was mainly to draw simple geometries in event display programs. We are currently investigating several alternatives for a true & efficient geometry package supporting;

- \-

  a disk data base with storage of multiple geometry versions

- \-

  an interactive editor and viewer

- \-

  with 3-d views

- \-

  but also 2-d cut views

- \-

  with interfaces to existing or future MC such as  **GEANT3** or  **GEANT4**

A second program called  **gh2root** (see  *http://root.cern.ch/root/gh2root.html*) generates automatically C++ code corresponding to the  **GEANT3 Zebra** structures  *JSET*, *JVERTX*, *JKINE*, *JHITS* and  *JDIGI.*

## SEE ALSO

[*root*(1)](/root/1.md), [*g2root*(1)](/g2root/1.md), *[h2root(1)](/h2root/1.md),*

and

*The ROOT Users Guide*

avaliable from the main  **ROOT** website:

*http://root.cern.ch*

## ORIGINAL AUTHORS

The ROOT team (see web page above):

**Rene Brun** and **Fons Rademakers**

## COPYRIGHT

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

## AUTHOR

This manual page was written by Christian Holm Christensen \<cholm@nbi.dk\>, for the Debian GNU/Linux system (but may be used by others).