.. _fields_arch_corba_services_page:

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FIELDS module CORBA services 
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To manage presentations in the FIELDS module, the following CORBA components and services are implemented:

* ``MED_ORB::MED_Gen`` is a CORBA engine of FIELDS module; it inherits ``Engine::EngineComponent`` from KERNEL module. It is aimed for
  
  * publishing of a structure of MED file (mesh, fields and timesteps) in *SALOMEDS*,
  * registering of presentations.

* ``MEDCALC::MEDFactory`` is another CORBA ``Engine::EngineComponent`` interface (it means that it can be retrieved in the CORBA context using the ``SALOME_LifeCycleCorba`` registry).
  It provides access to the CORBA services, which are used to manage FIELDS presentations:
     
    * ``MEDCALC::MEDDataManager`` - reads structure of the MED file; internally it uses *MEDCoupling* library for that purpose,
    * ``MEDCALC::MEDCommandsHistoryManager`` - collects a history of Python commands which are executed in the Python console in the FIELDS module and provides access to the sequence of commands,
    * ``MEDCALC::MEDPresentationManager`` - main service for creating FIELDS presentations and managing their parameters; it is used in :ref:`FIELDS GUI<fields_arch_gui_page>` to retrieve parameters of presentations 
      and :ref:`medcalc<fields_arch_medcacl_py_page>` Python package to create and update FIELDS presentations.