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     Geant4 - an Object-Oriented Toolkit for Simulation in HEP
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                            Example Transforms
                            -------------------
                            
This extended example demonstrates various ways of definition of 
3D transformations for placing volumes. 

The geometry setup consists of two trapezoid volumes which are placed 
in a world so that their axial symmetry axis is in given theta and phi 
polar angles. The various ways of placement are implemented in the 
TrDetectorConstruction class in the following private functions:
 - PlaceWithDirectMatrix()
 - PlaceWithInverseMatrix()
 - PlaceWithAxialRotations()
 - PlaceWithEulerAngles()
 - PlaceWithReflections()
which are then called from the Construct() function.
All methods define exactly same geometry except for the placement 
with reflection where trapezoids are placed with their symmetry axis 
in parallel with z-axis in order to make easier to check reflection 
visually. 

The method of placement can be selected interactively via the command
(see TrDetectorConstructionMessenger):
/transform/setMethod method

The example is defined with use of classes from the common examples.
These classes from common start with the ExG4 prefix while the
classes relevant to transfomation start with the Tr prefix.

To run example:
% transforms
PreInit> /transform/setMethod WithDirectMatrix
PreInit> /run/initialize
Init> /run/beamOn 1









