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GeoModel - A Detector Description Toolkit for HEP experiments

GeoModel is a complete toolkit to write and manage the detector description for High Energy Physics experiments.

Intro

The GeoModel Toolkit offers classes that provide geometrical primitives for describing detectors, as well as a set of tools for writing, accessing, handling, manipulating, dumping, restoring, visualizing, inspecting, and debugging the detector geometry.

GeoModel also offers many memory-saving techniques which lets developers to optimally describe their detectors while keeping the memory footprint very low.

GeoModel is a pure C++ toolkit with only minimal and ligthweight external dependencies.

The GeoModel Toolkit is also highly modular:

you can pick the modules and tools you need, and you will use only what you really need, without the fear of introducing extra external potentially heavyweight dependencies when not needed.

Features

Geometry Description

A complete set of shapes and geometrical primitives to describe your detector’s geometry

A set of ‘nodes’ to build your detector tree

Alignment

A smart mechanism to handle detector alignment, with multiple alignment costants kept in cache and synchronized

Virtual Geometry / Surfaces

Tools to describe and handle 2D surfaces as part of a Virtual Geometry, which can be placed and misaligned alongside the regular, full geometry

Very useful to describe a simplified Tracking Geometry and still move and handle together with the full geometry

Visualization

A complete, interactive visualization tool to check, inspect, debug your detector geometry in an easy way

GDML support

An exporter to export a GeoModel geometry into GDML

An importer to import a GDML geometry into GeoModel (work in progress)

Standalone Detector Simulation

Easy Geant4-based simulation

An interactive graphical interface to steer a standalone Geant4-based simulation of your detector, to get quick feedback on your detector while you’re still working on it

Clash Detection & Visualization

Standalone tools to identify clash points and overlaps between geometry volumes with a fast Geant4-based algorithm

Interactive visualization of clash points in the standalone GeoModel visualization module

Volume Computation

Methods to compute the volume of all shapes, included Boolean shapes, and store it in the GeoModel I/O file for later use

Mass calculation

A standalone mass calculator tool, to quickly compute the masses of your detector from the command line

Geantino Maps

A standalone tool to generate geantino maps of your newly built detector

The GeoModel Toolkit includes:

  • gmex, the geometry explorer, an interactive 3D geometry visualizer
  • gmstatistics, tool to monitor the memory consumption
  • fullsimlight, a command-line tool to run experiment agnostic Geant4 simulation, and its graphical user interface, fsl.
  • gmclash, a Geant4 based command-line tool to perform clash detection
  • gmgeantino, a Geant4 based command-line tool to generate geantino maps
  • gmmasscalc, a Geant4 based command-line tool to compute the mass of a given piece of detector geometry
  • gm2gdml and gdml2gm, command line tools to convert GeoModel to and from GDML
  • gmcat, a command line tool to assemble geometry from multiple inputs

External Dependencies

The GeoModel Toolkit offers C++ classes that provide geometrical primitives for describing detector geometry (e.g., shapes, logical/physical volumes, transformations), as well as a set of tools for writing, accessing, handling, manipulating, dumping, restoring, visualizing, inspecting, and debugging detector geometries.

  • The Eigen math library for the core packages

Additional external dependencies:

  • The lightweight SQLite file-based database for I/O, when the I/O module is used
  • The nlohmann_json JSON parser library to import external data, when the Visualization and Tools modules are used
  • The Apache Xerces-C XML parser library, when the XML interface of the Tools module is used
  • The open-source (“Community”) version of the Qt graphics framework for the GUI, when the Visualization module is used
  • The Coin and SoQt libraries for 3D graphics, when the Visualization module is used
  • The Geant4 detector simulation toolkit, when the standalone detector simulation module FullSimLight is used
  • The GoogleTest - Google Testing and Mocking framework, when the building of unit tests is requested

Last update:

2025-07-14 13:41:36.210020