G2ROOT(1)

💖 G2ROOT 💖

okay bestie, welcome to the General Commands Manual corner of the internet, section 1, where we talk about g2root — the lil glow-up machine that turns your crusty old GEANT geometry files into shiny ROOT files. no cap, it's giving ✨glow-up✨ energy and we're gonna walk through it together 🫶

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🌸 NAME 🌸

g2root — convert GEANT geometry files to ROOT files 🦋

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🎀 SYNOPSIS 🎀

g2rootd [-f map_name] geant_name macro_name

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👑 DESCRIPTION 👑

So here's the tea ☕ — you can convert a GEANT geometry (peep http://geant.cern.ch/ fore more on GEANT, iykyk) into a ROOT geometry, and it's literally just three steps. main character energy, no drama:

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 g2root program to convert the Zebra RZ file into a ROOT macro detector.C:

g2root 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 viewer)
root [4] TFile f("detector.root","NEW") //open a new root file
root [5] detector.Write() //Write the geometry structure
root [6] f.Write()

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💀 okay real talk for a sec. 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 🔗

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

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🦋 SEE ALSO 🦋

• root(1), h2root(1),
• and
• The ROOT Users Guide

available from the main ROOT website:

• http://root.cern

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🌈 ORIGINAL AUTHORS 🌈

The ROOT team (see web page above):

• Rene Brun and Fons Rademakers 👑

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💜 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 📬

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🎀 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). 🫶

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and that's the whole page bestie!! this one's from ROOT, Version 3 — mwah, go convert some geometry, you absolute icon 💅✨💖