LCD Weekly
Geometry Discussion
01/18/2005

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-naming collections and later lkp still unsolved problem
  -self-describing or
  -lkp catalog

-GODL
  -assigning hitsCollectionsNames on volume names

-system names -> collection names

-system IDs -> tracker, calorimeter ID

-LCIO
  -lkp of name by ID
    -how to lkp from id?

-calculation of hit ID

-plugin module
  -"find" external code by detector

-32/64 bit words
  -WL thinks problemmatic (me too)

-need CellId class in upper layer

-indexing from DD (WL)
  -specify in data format

-assign name to an ID chunk: "LayerNumber"

-bit masking, etc. needs to connect to LCIO file

-geometry URL (or similar) in LCIO file

-procedural advantage: switching to DB values is fairly easy

-analysis
  -don't need much geometry information
    -reconstruct XYZ
    -cell neighbors
    -layers  
  -CellId translators
  -direct entry in LCIO output file for key values (WL)

-avoid changing framework right now

-want Java parsing of GODL (NG)

-compact description
  -problemmatic! (JM)