BackgroundStateAbstractBase.h

/******************************************************************************************************
 * (C) 2014 markummitchell@github.com. This file is part of Engauge Digitizer, which is released      *
 * under GNU General Public License version 2 (GPLv2) or (at your option) any later version. See file *
 * LICENSE or go to gnu.org/licenses for details. Distribution requires prior written permission.     *
 ******************************************************************************************************/
 
#ifndef BACKGROUND_STATE_ABSTRACT_BASE_H
#define BACKGROUND_STATE_ABSTRACT_BASE_H
 
#include <QGraphicsPixmapItem>
#include <QImage>
 
enum BackgroundState {
  BACKGROUND_STATE_CURVE,
  BACKGROUND_STATE_NONE,
  BACKGROUND_STATE_ORIGINAL,
  BACKGROUND_STATE_UNLOADED,
  NUM_BACKGROUND_STATES
};
 
class BackgroundStateContext;
class DocumentModelColorFilter;
class DocumentModelGridRemoval;
class GraphicsScene;
class GraphicsView;
class Transformation;
 
class BackgroundStateAbstractBase
{
 public:
  BackgroundStateAbstractBase(BackgroundStateContext &context,
                              GraphicsScene &scene);
  ~BackgroundStateAbstractBase();
 
  virtual void begin() = 0;
 
  BackgroundStateContext &context();
 
  const BackgroundStateContext &context() const;
 
  virtual void end() = 0;
 
  virtual void fitInView (GraphicsView &view) = 0;
 
  QImage image () const;
 
  QGraphicsPixmapItem &imageItem () const;
 
  GraphicsScene &scene();
 
  const GraphicsScene &scene() const;
 
  virtual void setCurveSelected (const Transformation &transformation,
                                 const DocumentModelGridRemoval &modelGridRemoval,
                                 const DocumentModelColorFilter &colorFilter,
                                 const QString &curveSelected) = 0;
 
  virtual void setPixmap (const Transformation &transformation,
                          const DocumentModelGridRemoval &modelGridRemoval,
                          const DocumentModelColorFilter &modelColorFilter,
                          const QPixmap &pixmap) = 0;
 
  virtual QString state() const = 0;
 
  virtual void updateColorFilter (const Transformation &transformation,
                                  const DocumentModelGridRemoval &modelGridRemoval,
                                  const DocumentModelColorFilter &modelColorFilter) = 0;
 
 protected:
 
  void setImageVisible (bool visible);
 
  void setProcessedPixmap (const QPixmap &pixmap);
 
 private:
  BackgroundStateAbstractBase();
 
  BackgroundStateContext &m_context;
  GraphicsScene &m_scene;
 
  // Each state has its own image, although only one is shown at a time. This is null if an image has not been defined yet,
  // so we can eliminate a dependency on the ordering of the state transitions and the update of the image by setPixmap
  QGraphicsPixmapItem *m_imageItem;
 
  QImage m_image; // Original image. This is stored in addition to m_imageItem since m_imageItem cannot be used when invisible
};
 
#endif // BACKGROUND_STATE_ABSTRACT_BASE_H