Geometry working group

Work items for 2013

List with description

1. Architecture review:
   • Adaptation/improvement of relevant classes for multi-threading
     • Identify best implementation choices to be applied for making any part of the geometry modeller thread-safe
   • Redesign and optimisation of relevant MT split classes
     • Optimise implementation of thread-safety for classes affected by mixing of R/W and R-only data; introduce comments/tags to allow for easier identification of invariant data
     • Evaluate possibility to reduce or completely eliminate RW data and its impact to exposed interfaces
   • Verification of multi-threading for all features
     • Test and benchmark on multi-threaded runs various features provided by the modeller (nested-parameterisations, divisions, regular navigation, dynamic geometries, parallel navigation, etc...)
2. Navigation & optimisation:
   • Fix remaining issues for precise ComputeSafety() in navigation
     • Refine and optimize the alternative Computesafety() for use by physics processes (mainly EM) for measuring the exact safety value, not limited by voxels boundaries
     • Adapt multiple-scattering EM process to make use of the new feature, after having optimized its performance
   • Profiling and optimisation of multiple navigation
     • Revise the design and implementation of multiple navigation and coupled-transportation
     • Identify any open issue in application to fast-simulation, scoring and layered tracking geometries and in conjuction with magnetic field transport
     • Identify possible CPU performance penalties which may be introduced with the activation of coupled-transportation. Optimize overall performance (ATLAS request)
   • Refactor navigator to separate thread-dependent state
     • Review design and implementation of G4Navigator to separate live state from the main class and allow for more optimised solution for thread-local storage
3. New features:
   • Complete implementation of unified solids library
     • Complete implementation of remaining solids in the unified library for geometrical shapes for Geant4 and Root.
     • Provide integration of the new library in the main code base of the Geant4 geometry modeller
   • Identify first/last step in a volume for curved tracks
     • Feature currently possible only for linear track; requires to be extended also for curved tracks in magnetic field
4. Code cleanup:
   • Removal of BREP solids module
     • End of support and development for the BREPS module. Being archived
   • Replacement of built-in UI commands for overlaps checks
     • Removal of classes and algorithms implementing current built-in UI commands for overlaps checks based on super-imposition of 'grid' lines
     • Replace UI commands for overlaps checks with corresponding precise functionality provided by solids for generated points on surface on-demand

Previous years planned activities