The ROOT geometry package

The new ROOT (in: Proceeding of AIHENP’96, Lausanne, September 1996; http://root.cern.ch/) geometry package is a tool designed for building, browsing, tracking and visualizing a detector geometry. The code works standalone with respect to any tracking Monte-Carlo engine; therefore, it does not contain any constraints related to physics. However, the package defines a number of hooks in order to ease-up tracking, allowing user-defined objects to be attached to the basic architectural structures or superimposed on top of them. The modeling functionality was designed to optimize particle transport through complex geometries and it is accessible in an easy and transparent way. The package is currently under development and new features will be implemented, but the basic functionality has already been extensively tested on several detector geometries. The final goal is to be able to use the same geometry for several purposes, such as tracking, reconstruction or visualization, taking advantage of the ROOT features related to bookkeeping, I/O, histograming, browsing and graphical interfaces.