Preserve output imageview position on reload / params change

Author: noobie-iv

src/core/ImageViewBase.cpp

@@ -1078,6 +1078,32 @@ ImageViewBase::setWidgetFocalPointWithoutMoving(QPointF const new_widget_fp)
                          );
 }
 
+ImageViewBase::Position
+ImageViewBase::getPosition() const
+{
+    QPointF const anchor_image(widgetToImage().map(rect().center()));
+    QPointF const anchor(
+        anchor_image.x() / m_image.width(),
+        anchor_image.y() / m_image.height()
+    );
+
+    return Position(m_zoom, anchor);
+}
+
+void
+ImageViewBase::setPosition(Position const& position)
+{
+    QPointF const anchor(position.anchor());
+    QPointF const anchor_image(
+        m_image.width() * anchor.x(),
+        m_image.height() * anchor.y()
+    );
+    QPointF const anchor_widget(imageToWidget().map(anchor_image));
+
+    setWidgetFocalPointWithoutMoving(anchor_widget);
+    setZoomLevel(position.zoom());
+}
+
 /**
  * Returns true if m_hqPixmap is valid and up to date.
  */

src/core/ImageViewBase.h

@@ -64,6 +64,29 @@ class ImageViewBase : public QAbstractScrollArea
 public:
     enum FocalPointMode { CENTER_IF_FITS, DONT_CENTER };
 
+    class Position
+    {
+    public:
+        Position(double zoom, QPointF const& anchor)
+            : m_zoom(zoom)
+            , m_anchor(anchor)
+        {
+        }
+
+        double zoom() const
+        {
+            return m_zoom;
+        }
+
+        QPointF anchor() const
+        {
+            return m_anchor;
+        }
+    private:
+        double m_zoom;
+        QPointF m_anchor;
+    };
+
     /**
      * \brief ImageViewBase constructor.
      *
@@ -226,6 +249,10 @@ class ImageViewBase : public QAbstractScrollArea
      */
     void setWidgetFocalPointWithoutMoving(QPointF new_widget_fp);
 
+    Position getPosition() const;
+
+    void setPosition(Position const& position);
+
     /**
      * \brief Updates image-to-virtual and recalculates
      *        virtual-to-widget transformations.

src/core/filters/output/ImageView.cpp

@@ -20,25 +20,36 @@
 
 #include "ImagePresentation.h"
 #include "OutputMargins.h"
+#include "Settings.h"
 
 namespace output
 {
 
-ImageView::ImageView(QImage const& image, QImage const& downscaled_image)
-    :   ImageViewBase(
-            image, downscaled_image,
-            ImagePresentation(QTransform(), QRectF(image.rect())),
-            OutputMargins()
-        ),
-        m_dragHandler(*this),
-        m_zoomHandler(*this)
+ImageView::ImageView(IntrusivePtr<Settings> const& settings, PageId const& page_id,
+                     QImage const& image, QImage const& downscaled_image)
+    : ImageViewBase(
+        image, downscaled_image,
+        ImagePresentation(QTransform(), QRectF(image.rect())),
+        OutputMargins()
+    )
+    , m_ptrSettings(settings)
+    , m_pageId(page_id)
+    , m_dragHandler(*this)
+    , m_zoomHandler(*this)
 {
     rootInteractionHandler().makeLastFollower(m_dragHandler);
     rootInteractionHandler().makeLastFollower(m_zoomHandler);
+
+    boost::optional<ImageViewBase::Position> const position = settings->getImageViewPosition(page_id);
+    if (position)
+    {
+        setPosition(position.value());
+    }
 }
 
 ImageView::~ImageView()
 {
+    m_ptrSettings->setImageViewPosition(m_pageId, getPosition());
 }
 
 } // namespace output

src/core/filters/output/ImageView.h

@@ -22,21 +22,27 @@
 #include "ImageViewBase.h"
 #include "DragHandler.h"
 #include "ZoomHandler.h"
-#include <QColor>
+#include "IntrusivePtr.h"
+#include "PageId.h"
 
 class ImageTransformation;
 
 namespace output
 {
 
+class Settings;
+
 class ImageView : public ImageViewBase
 {
     Q_OBJECT
 public:
-    ImageView(QImage const& image, QImage const& downscaled_image);
+    ImageView(IntrusivePtr<Settings> const& settings, PageId const& page_id,
+              QImage const& image, QImage const& downscaled_image);
 
     virtual ~ImageView();
 private:
+    IntrusivePtr<Settings> m_ptrSettings;
+    PageId const m_pageId;
     DragHandler m_dragHandler;
     ZoomHandler m_zoomHandler;
 };

src/core/filters/output/Settings.cpp

@@ -56,6 +56,7 @@ Settings::clear()
     m_perPageOutputParams.clear();
     m_perPagePictureZones.clear();
     m_perPageFillZones.clear();
+    m_perPageImageviewPositions.clear();
 }
 
 void
@@ -67,6 +68,7 @@ Settings::performRelinking(AbstractRelinker const& relinker)
     PerPageOutputParams new_output_params;
     PerPageZones new_picture_zones;
     PerPageZones new_fill_zones;
+    PerPageImageviewPositions new_imageview_positions;
 
     for (PerPageParams::value_type const& kv : m_perPageParams) {
         RelinkablePath const old_path(kv.first.imageId().filePath(), RelinkablePath::File);
@@ -96,10 +98,18 @@ Settings::performRelinking(AbstractRelinker const& relinker)
         new_fill_zones.insert(PerPageZones::value_type(new_page_id, kv.second));
     }
 
+    for (PerPageImageviewPositions::value_type const& kv : m_perPageImageviewPositions) {
+        RelinkablePath const old_path(kv.first.imageId().filePath(), RelinkablePath::File);
+        PageId new_page_id(kv.first);
+        new_page_id.imageId().setFilePath(relinker.substitutionPathFor(old_path));
+        new_imageview_positions.insert(PerPageImageviewPositions::value_type(new_page_id, kv.second));
+    }
+
     m_perPageParams.swap(new_params);
     m_perPageOutputParams.swap(new_output_params);
     m_perPagePictureZones.swap(new_picture_zones);
     m_perPageFillZones.swap(new_fill_zones);
+    m_perPageImageviewPositions.swap(new_imageview_positions);
 }
 
 Params
@@ -289,4 +299,25 @@ Settings::initialFillZoneProps()
     return props;
 }
 
+boost::optional<ImageViewBase::Position>
+Settings::getImageViewPosition(PageId const& page_id) const
+{
+    QMutexLocker const locker(&m_mutex);
+
+    PerPageImageviewPositions::const_iterator const it(m_perPageImageviewPositions.find(page_id));
+    if (it != m_perPageImageviewPositions.end()) {
+        return it->second;
+    }
+    else {
+        return boost::optional<ImageViewBase::Position>();
+    }
+}
+
+void
+Settings::setImageViewPosition(PageId const& page_id, ImageViewBase::Position const& imageview_position)
+{
+    QMutexLocker const locker(&m_mutex);
+    Utils::mapSetValue(m_perPageImageviewPositions, page_id, imageview_position);
+}
+
 } // namespace output

src/core/filters/output/Settings.h

@@ -26,12 +26,14 @@
 #include "ColorParams.h"
 #include "Params.h"
 #include "OutputParams.h"
+#include "ImageViewBase.h"
 #include "DespeckleLevel.h"
 #include "ZoneSet.h"
 #include "PropertySet.h"
 #include <QMutex>
 #include <map>
 #include <memory>
+#include <boost/optional.hpp>
 //begin of modified by monday2000
 //Picture_Shape
 #include "Params.h"
@@ -91,10 +93,15 @@ class Settings : public RefCountable
     void setDefaultPictureZoneProperties(PropertySet const& props);
 
     void setDefaultFillZoneProperties(PropertySet const& props);
+
+    boost::optional<ImageViewBase::Position> getImageViewPosition(PageId const& page_id) const;
+
+    void setImageViewPosition(PageId const& page_id, ImageViewBase::Position const& imageview_position);
 private:
     typedef std::map<PageId, Params> PerPageParams;
     typedef std::map<PageId, OutputParams> PerPageOutputParams;
     typedef std::map<PageId, ZoneSet> PerPageZones;
+    typedef std::map<PageId, boost::optional<ImageViewBase::Position> >  PerPageImageviewPositions;
 
     static PropertySet initialPictureZoneProps();
 
@@ -105,6 +112,7 @@ class Settings : public RefCountable
     PerPageOutputParams m_perPageOutputParams;
     PerPageZones m_perPagePictureZones;
     PerPageZones m_perPageFillZones;
+    PerPageImageviewPositions m_perPageImageviewPositions;
     PropertySet m_defaultPictureZoneProps;
     PropertySet m_defaultFillZoneProps;
     int m_compression;

src/core/filters/output/Task.cpp

@@ -618,7 +618,7 @@ Task::UiUpdater::updateUI(FilterUiInterface* ui)
     }
 
     std::unique_ptr<ImageViewBase> image_view(
-        new ImageView(m_outputImage, m_downscaledOutputImage)
+        new ImageView(m_ptrSettings, m_pageId, m_outputImage, m_downscaledOutputImage)
     );
 
     std::shared_ptr<QImage> alt_image_ptr;