Geometry Work Plan for 2021

Version 1.0

NOTE: Any dates assigned to items are to be considered just indicative.
- Items marked with refer to new developments.
- Items marked with will involve new man-power or contribution from external sources interested in the project.
- Items marked with will require coordination with more than one Working Group.
- Items marked with (*) may or may not be achieved.

  1. Architecture:
    • Review adoption of workspaces for task-based parallelism - (1)/(2)

      In the context of bringing task-based parallelism the default MT model for Geant4, review thread-local storage use and adoption of workspaces.

  2. Navigation & optimisation:
    • Interface with navigator based on VecGeom - (1)

      Provide first optional interface/adapter for enabling navigation capabilities in VecGeom.

    • Separate safety computation and its state from navigator - (2)/(*)

      Loose coupling of G4Navigator in the computation of the safety distances from geometrical boundaries, factorising out the implementation now included in G4Navigator class, to get rid of potential side effects.

    • Revision of the transportation processes; specialised transportation processes for neutral and charged particles - (2)/(*)

      Factorise implementation of G4Transportation (and G4CoupledTransportation) for considering having at least two specialised transportation processes, one for neutral and one for charged particles (perhaps also one specific for optical photons), in order to optimise and speed-up transport by reducing redundant calls and code branches.

    • Prototype navigation indexing class - (2)/(*)

      An integer index identifying all touchables, or those up to a given level.
      Transportation process that uses this to replace touchable handles.

  3. Field transport:
    • Addition of QSS integration methods (Quantized State Simulation) - (1)/(2)

      Alternative integration method which creates adapted polynomials and evaluates the limit of their validity.

    • Review accuracy of boundary crossing in field - (1)/(2)

      Study boundary crossing accuracy when field integration is enabled, reviewing behavior when using current default parameters in typical geometry setups.

  4. Solids modelling:
    • Enable VecGeom shapes as default - (2)/(*)

      Prepare infrastructure (also for standalone build of Geant4) with solids from the VecGeom library enabled as default.

  • Routine activities
    • Review of user documentation

(1) First semester
(2) Second semester

Created: 19 January 2021
Modified: 10 September 2021