Gabriele Cosmo
118 lines
3.1 KiB
Plaintext
118 lines
3.1 KiB
Plaintext
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=========================================================
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Geant4 - an Object-Oriented Toolkit for Simulation in HEP
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=========================================================
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Example TextGeom
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----------------
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This example illustrates the use of the text geometry.
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1.- GEOMETRY EXAMPLES
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Several examples of text geometries are provided:
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g4geom_simple.txt :
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- Simple construction of materials and single placements
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g4geom_matemixt.txt :
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- Isotopes, elements and materials
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g4geom_boolean.txt :
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- Boolean solids
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g4geom_reflections.txt :
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- Reflections
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g4geom_replicas.txt :
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- Replicas
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g4geom_divisions.txt :
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- Divisions
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g4geom_paramLinear.txt :
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- Linear parameterisations
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g4geom_paramSquare.txt :
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- Square parameterisations
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g4geom_assembly.txt :
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- Assembly placements
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2.- HOW TO START ?
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- execute textGeom in 'batch' mode from macro file
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% textGeom run.mac
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It will read the geometry from a file named 'g4geom.txt', and it will create a
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VRML2 file to visualise the geometry.
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Therefore if you want to try any of the above-mentioned files, copy it to a
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file with this name,
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3.- DEFINING A SENSITIVE DETECTOR
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The detector construction class ExTGDetectorConstructionWithSD shows how to
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access a volume of the text geometry and assign to it a sensitive detector.
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To use it, replace at exampleTextGeom.cc the line
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runManager->SetUserInitialization(new ExTGDetectorConstruction);
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by
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runManager->SetUserInitialization(new ExTGDetectorConstructionWithSD);
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and recompile.
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It will use the geometry from the file 'g4geom_SD.txt'
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4.- MIXING TEXT AND C++ GEOMETRIES
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The detector construction class ExTGDetectorConstructionWithCpp shows how to
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create a volume with C++ and place it in the world or inside a volume defined
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in the text geometry.
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To use it, replace at exampleTextGeom.cc the line
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runManager->SetUserInitialization(new ExTGDetectorConstruction);
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by
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runManager->SetUserInitialization(new ExTGDetectorConstructionWithCpp);
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and recompile.
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It will use the geometry from the file 'g4geom_simple.txt'
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5.- CREATING NEW TAGS IN THE TEXT GEOMETRY: DEFINING CUTS PER REGION
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The detector construction class ExTGDetectorConstructionWithCuts, together with
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ExTGRCLineProcessor, ExTGRCDetectorBuilder, ExTGRCRegionCutsMgr and
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ExTGRCRegionData show how to add a couple of tags, ':REGION' and ':CUT', that
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allow to define cuts per region in your input geometry text file.
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To use it, replace at exampleTextGeom.cc the line
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runManager->SetUserInitialization(new ExTGDetectorConstruction);
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by
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runManager->SetUserInitialization(new ExTGDetectorConstructionWithCuts);
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and recompile.
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It will use the geometry from the file 'g4geom_cutsPerRegion.txt'
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6.- DUMP THE IN-MEMORY GEOMETRY TO TEXT FILE
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The run action 'ExTGRunAction' triggers the writing of the in-memory Geant4
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geometry to a text file.
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To use it you just have to uncomment in exampleTextGeom.cc the line
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runManager->SetUserAction(new ExTGRunAction);
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and it will read the geometry from the file 'g4geom.txt' and will write the
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geometry in a file named 'geom.txt'
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