view transform/TransformFactory.h @ 6:44bbf5793d84

* Rework handling of layer properties in file I/O -- we now get the individual
  layers to load and save them rather than doing it via generic property lists
  in the base class, so as to ensure we read and write meaningful values rather
  than generic int values requiring conversion.

/* -*- c-basic-offset: 4 -*-  vi:set ts=8 sts=4 sw=4: */

/*
    A waveform viewer and audio annotation editor.
    Chris Cannam, Queen Mary University of London, 2005-2006
   
    This is experimental software.  Not for distribution.
*/

#ifndef _TRANSFORM_FACTORY_H_
#define _TRANSFORM_FACTORY_H_

#include "Transform.h"

class TransformFactory : public QObject
{
    Q_OBJECT

public:
    virtual ~TransformFactory();

    static TransformFactory *instance();

    // The name is intended to be computer-referencable, and unique
    // within the application.  The description should be
    // human-readable, and does not have to be unique.

    struct TransformDesc {
	TransformDesc(TransformName _name, QString _description = "") :
	    name(_name), description(_description) { }
	TransformName name;
	QString description;
    };
    typedef std::vector<TransformDesc> TransformList;

    TransformList getAllTransforms();

    /**
     * Return the output model resulting from applying the named
     * transform to the given input model.  The transform may still be
     * working in the background when the model is returned; check the
     * output model's isReady completion status for more details.
     *
     * If the transform is unknown or the input model is not an
     * appropriate type for the given transform, or if some other
     * problem occurs, return 0.
     * 
     * The returned model is owned by the caller and must be deleted
     * when no longer needed.
     */
    Model *transform(TransformName name, Model *inputModel);

    //!!! Need some way to indicate that the input model has changed /
    //been deleted so as not to blow up backgrounded transform!  -- Or
    //indeed, if the output model has been deleted -- could equally
    //well happen!

    //!!! Need transform category!
	
protected slots:
    void transformFinished();

protected:
    Transform *createTransform(TransformName name, Model *inputModel);
    Transform *createTransform(TransformName name, Model *inputModel,
			       bool start);

    static TransformFactory *m_instance;
};


#endif