Wizt::AsynchronCreator Class Reference

A Creator object that generates its content on demand, deferred, in a subthread, via the VISH Thread Interface VTask. More...

#include <AsynchronCreator.hpp>

List of all members.

Classes

• struct ComputationTask

Public Types

• typedef Fiber::CreativeArrayBase CreativeArrayBase
• typedef Fiber::MemBase MemBase

Public Member Functions

• AsynchronCreator (RefPtr< VValueParameter< VThreadManager > > &TMPar, const RefPtr< Cache > &theCache=Cache::MemCache())
• AsynchronCreator (VCotask *CoTask, const RefPtr< Cache > &theCache=Cache::MemCache())
• override bool release ()
• virtual RefPtr< Fiber::MemBase > compute ()=0
• bool isRunning () const
• override RefPtr< MemBase > create ()
• override RefPtr< MemBase > get () const

Public Attributes

• RefPtr< VValueParameter
  < VThreadManager > > ThreadManagerParam
• bool do_async

  Flag to determine whether the deferred operation shall be executed asynchroneously, i.e.
  

• RefPtr< ComputationTask > CT

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Detailed Description

A Creator object that generates its content on demand, deferred, in a subthread, via the VISH Thread Interface VTask.

class   MyObject : public VObject
{
        Slot            ThreadManagerSlot;

public:
        MyObject(...)
        {
                ThreadManagerSlot = addParameter( "computationThread", 2, new VValueParameter<VThreadManager>() );
        }

        override bool update(VRequest&Req, double precision)
        {
                ...
                // First, get a field object from somewhere
        RefPtr<Field>&myField = ...;
                // We seek to work on the field's global Creator
        RefPtr<AnalyticCreator> AC = myField->getCreator();
                if (!AC)
                {
                        // If there is no creator yet, define one.
                        // No action will be performed here, and some action
                        // will only be triggered if the data of this Creator
                        // will actually be requested elsewhere.
                        myField->setCreator( new AnalyticCreator( ThreadManagerSlot->param ) );
                        touch();
                }

                //
                // If running, terminate the execution of the data graph.
                // This is one of the rare cases where the update() function 
                // may return false. What this means is that the data graph will
                // no longer be traversed this time, and the global request for
                // creation of data will be denied. Then, this request may be
                // restarted, but the application can do something else in the
                // meanwhile. Alternatively, could also wait here, until the
                // thread has finished. Though, this were a waste of computational
                // resources to just spend time here with doing nothing.
                //
                if (AC && AC->isRunning() )
                        return false;

                // analytic creator exists and can be used to do something with it
                // but most likely we just want to return now, since all activity
                // will be done by the AnalyticCreator object.
                ...
                return true;
        }
};

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Member Data Documentation

bool Wizt::AsynchronCreator::do_async

Flag to determine whether the deferred operation shall be executed asynchroneously, i.e.

within another thread.