Discussion on managing the coexistence of CDF and

Discussion on managing the coexistence of CDF and XML geometry files LHCb Software Week 5 -7 April 2000 P. Mato / CERN 6/4/2000 Managing the coexistance of CDF and XML geometry files 1

Problem Statement u Today’s situation – The geometry information is available to Fortran algorithms from CDF files by specific Fortran detector description code. u Final situation – The geometry information will be made available to GAUDI algorithms from XML files (or database) by a combination of generic and specific converters. u Intermediate situation (hybrid) – Fortran code (in particular Geant 3) will get the geometry from CDF files and C++ algorithms from XML files. Ø Ø How can we made sure that the two “persistent” geometries are consistent? Even if BRUNEL is completely in C++, Sicb. MC will still be in Fortran for a while. 6/4/2000 Managing the coexistance of CDF and XML geometry files 2

The Ingredients CDF XML specific 6/4/2000 Geom XML Cnv Commons Recons Alg Geant 3 Geo G 3 Recons Alg T. Det. Store G 4 Cnv G 4 Geo Managing the coexistance of CDF and XML geometry files G 4 3

Option A CDF XML Geom Geant 3 Geo G 3 Recons Alg XML Cnv T. Det. Store The two geometries are edited by hand, making sure that they are compatible 6/4/2000 Commons Recons Alg G 4 Cnv G 4 Geo Managing the coexistance of CDF and XML geometry files G 4 4

Option B CDF Geom CDF to XML XML Cnv Geant 3 Geo G 3 Recons Alg T. Det. Store Rewrite specific Fortran routines (based on existing ones) to generate XML from CDF 6/4/2000 Commons Recons Alg G 4 Cnv G 4 Geo Managing the coexistance of CDF and XML geometry files G 4 5

Option C CDF Geom XML to CDF XML Cnv Recons Alg Geant 3 Geo G 3 Recons Alg T. Det. Store Sections of the XML file contain CDF fragments, which can be extracted. 6/4/2000 Commons G 4 Cnv G 4 Geo Managing the coexistance of CDF and XML geometry files G 4 6

Pros and Cons 6/4/2000 Managing the coexistance of CDF and XML geometry files 7