abstractprocessor.h

// ================================================================================================
// 
// This file is part of the TUMVis Visualization Framework.
// 
// If not explicitly stated otherwise: Copyright (C) 2012, all rights reserved,
//      Christian Schulte zu Berge (christian.szb@in.tum.de)
//      Chair for Computer Aided Medical Procedures
//      Technische Universität München
//      Boltzmannstr. 3, 85748 Garching b. München, Germany
// 
// The licensing of this softare is not yet resolved. Until then, redistribution in source or
// binary forms outside the CAMP chair is not permitted, unless explicitly stated in legal form.
// However, the names of the original authors and the above copyright notice must retain in its
// original state in any case.
// 
// Legal disclaimer provided by the BSD license:
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
// IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 
// AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR 
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 
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// POSSIBILITY OF SUCH DAMAGE.
// 
// ================================================================================================

#ifndef PROCESSOR_H__
#define PROCESSOR_H__

#include "sigslot/sigslot.h"
#include "tgt/logmanager.h"
#include "core/datastructures/datacontainer.h"
#include "core/tools/invalidationlevel.h"
#include "core/properties/propertycollection.h"

#include <string>
#include <vector>

namespace TUMVis {
    class AbstractProperty;

    /**
     * Abstract base class for TUMVis Processors.
     * A processor implements a specific task, which it performs on the DataCollection passed
     * during process(). Properties provide a transparent layer for adjusting the processor's 
     * behaviour.
     * Once a processor has finished it sets it should set its invalidation level to valid. As
     * soon as one of its properties changes, the processor will be notified and possibliy
     * change its invalidation level. Observing pipelines will be notified of this and can
     * and have to decide which part of the pipeline has to be re-evaluated wrt. the processor's
     * invalidation level.
     * 
     * \sa AbstractPipeline
     */
    class AbstractProcessor : public HasPropertyCollection {

    /**
     * We have to find a trade-off:
     * On the one hand, we want to follow the information-hiding concept and keep the processor's
     * properties private. On the other hand pipelines will usually want direct access to them
     * (e.g. in order to setup data IDs or property sharing) and the properties in the PropertyCollection
     * are not strongly typed. Hence, we declare AbstractPipeline as our friend.
     */
    friend class AbstractPipeline;  // TODO: this does not work as intended...

    public:

        /**
         * Creates a AbstractProcessor.
         */
        AbstractProcessor();

        /**
         * Virtual Destructor
         **/
        virtual ~AbstractProcessor();


        /**
         * Initializes the processor.
         * Everything that requires a valid OpenGL context or is otherwise expensive gets in here.
         * 
         * \note    When overwriting this method, make sure to call the base class version first.
         */
        virtual void init();
        
        /**
         * Deinitializes this processor.
         * \note    When overwriting this method, make sure to call the base class version at the end.
         */
        virtual void deinit();

        /**
         * Execute this processor.
         * \param data      DataContainer to work on.
         **/
        virtual void process(DataContainer& data) = 0;

        /**
         * Returns the invalidation level of this processor.
         * \return _invalidationLevel
         */
        const InvalidationLevel& getInvalidationLevel() const;

        /**
         * Gets the name of this very processor. To be defined by every subclass.
         * \return  The name of this processor.
         */
        virtual const std::string getName() const = 0;

        /**
         * Gets a description of this processor. To be defined by every subclass.
         * \return  A description what this processor does.
         */
        virtual const std::string getDescription() const = 0;

        /**
         * Update the processor's invalidation level by \a il.
         * If \a il is VALID, the processor's invalidation level will be set to VALID.
         * If \a il is one of the INVALID_X state, the processor's corresponding flag will be set.
         * \param il    Invalidation level to apply.
         */
        void applyInvalidationLevel(InvalidationLevel il);
        
        /**
         * Locks all properties in the processor's PropertyCollection and marks them as "in use".
         * \sa  AbstractProcessor::unlock
         */
        void lockProperties();

        /**
         * Unlocks all properties in the processor's PropertyCollection and marks them as "not in use".
         * \sa  AbstractProcessor::lock
         */
        void unlockProperties();


        /// Signal emitted when the processor has been invalidated.
        sigslot::signal1<const AbstractProcessor*> s_invalidated;

        /**
         * Slot getting called when one of the observed properties changed and notifies its observers.
         * \param   prop    Property that emitted the signal
         */
        virtual void onPropertyChanged(const AbstractProperty* prop);


    protected:
        InvalidationLevel _invalidationLevel;       ///< current invalidation level of this processor



        static const std::string loggerCat_;
    };

}

#endif // PROCESSOR_H__