diff --git a/libs/image/lazybrush/kis_colorize_mask.cpp b/libs/image/lazybrush/kis_colorize_mask.cpp
index 295f5425b1..b0a53c644b 100644
--- a/libs/image/lazybrush/kis_colorize_mask.cpp
+++ b/libs/image/lazybrush/kis_colorize_mask.cpp
@@ -1,1168 +1,1176 @@
 /*
  *  Copyright (c) 2016 Dmitry Kazakov <dimula73@gmail.com>
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
  *  the Free Software Foundation; either version 2 of the License, or
  *  (at your option) any later version.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  */
 
 #include "kis_colorize_mask.h"
 
 #include <QCoreApplication>
 #include <QStack>
 
 #include <KoColorSpaceRegistry.h>
 #include "kis_pixel_selection.h"
 
 #include "kis_icon_utils.h"
 
 #include "kis_node_visitor.h"
 #include "kis_processing_visitor.h"
 #include "kis_painter.h"
 #include "kis_fill_painter.h"
 #include "kis_lazy_fill_tools.h"
 #include "kis_cached_paint_device.h"
 #include "kis_paint_device_debug_utils.h"
 #include "kis_layer_properties_icons.h"
 #include "kis_thread_safe_signal_compressor.h"
 
 #include "kis_colorize_stroke_strategy.h"
 #include "kis_multiway_cut.h"
 #include "kis_image.h"
 #include "kis_layer.h"
 #include "kis_macro_based_undo_store.h"
 #include "kis_post_execution_undo_adapter.h"
 #include "kis_command_utils.h"
 #include "kis_processing_applicator.h"
 #include "krita_utils.h"
 
 
 using namespace KisLazyFillTools;
 
 struct KisColorizeMask::Private
 {
     Private(KisColorizeMask *_q)
         : q(_q),
           coloringProjection(new KisPaintDevice(KoColorSpaceRegistry::instance()->rgb8())),
           fakePaintDevice(new KisPaintDevice(KoColorSpaceRegistry::instance()->rgb8())),
           filteredSource(new KisPaintDevice(KoColorSpaceRegistry::instance()->rgb8())),
           needAddCurrentKeyStroke(false),
           showKeyStrokes(true),
           showColoring(true),
           needsUpdate(true),
           originalSequenceNumber(-1),
           updateCompressor(1000, KisSignalCompressor::FIRST_ACTIVE_POSTPONE_NEXT),
           dirtyParentUpdateCompressor(200, KisSignalCompressor::FIRST_ACTIVE_POSTPONE_NEXT),
           prefilterRecalculationCompressor(1000, KisSignalCompressor::POSTPONE),
           updateIsRunning(false),
           filteringOptions(false, 4.0, 15, 0.7),
           limitToDeviceBounds(false)
     {
     }
 
     Private(const Private &rhs, KisColorizeMask *_q)
         : q(_q),
           coloringProjection(new KisPaintDevice(*rhs.coloringProjection)),
           fakePaintDevice(new KisPaintDevice(*rhs.fakePaintDevice)),
           filteredSource(new KisPaintDevice(*rhs.filteredSource)),
           filteredDeviceBounds(rhs.filteredDeviceBounds),
           needAddCurrentKeyStroke(rhs.needAddCurrentKeyStroke),
           showKeyStrokes(rhs.showKeyStrokes),
           showColoring(rhs.showColoring),
           needsUpdate(false),
           originalSequenceNumber(-1),
           updateCompressor(1000, KisSignalCompressor::FIRST_ACTIVE_POSTPONE_NEXT),
           dirtyParentUpdateCompressor(200, KisSignalCompressor::FIRST_ACTIVE_POSTPONE_NEXT),
           prefilterRecalculationCompressor(1000, KisSignalCompressor::POSTPONE),
           offset(rhs.offset),
           updateIsRunning(false),
           filteringOptions(rhs.filteringOptions),
           limitToDeviceBounds(rhs.limitToDeviceBounds)
     {
         Q_FOREACH (const KeyStroke &stroke, rhs.keyStrokes) {
             keyStrokes << KeyStroke(KisPaintDeviceSP(new KisPaintDevice(*stroke.dev)), stroke.color, stroke.isTransparent);
         }
     }
 
     KisColorizeMask *q = 0;
 
     QList<KeyStroke> keyStrokes;
     KisPaintDeviceSP coloringProjection;
     KisPaintDeviceSP fakePaintDevice;
     KisPaintDeviceSP filteredSource;
     QRect filteredDeviceBounds;
 
     KoColor currentColor;
     KisPaintDeviceSP currentKeyStrokeDevice;
     bool needAddCurrentKeyStroke;
 
     bool showKeyStrokes;
     bool showColoring;
 
     KisCachedSelection cachedSelection;
     KisCachedSelection cachedConversionSelection;
 
     bool needsUpdate;
     int originalSequenceNumber;
 
     KisThreadSafeSignalCompressor updateCompressor;
     KisThreadSafeSignalCompressor dirtyParentUpdateCompressor;
     KisThreadSafeSignalCompressor prefilterRecalculationCompressor;
     QPoint offset;
 
     bool updateIsRunning;
     QStack<QRect> extentBeforeUpdateStart;
 
     FilteringOptions filteringOptions;
     bool filteringDirty = true;
 
     bool limitToDeviceBounds = false;
 
     bool filteredSourceValid(KisPaintDeviceSP parentDevice) {
         return !filteringDirty && originalSequenceNumber == parentDevice->sequenceNumber();
     }
 
     void setNeedsUpdateImpl(bool value, bool requestedByUser);
 
     bool shouldShowFilteredSource() const;
     bool shouldShowColoring() const;
 };
 
 KisColorizeMask::KisColorizeMask()
     : m_d(new Private(this))
 {
     connect(&m_d->updateCompressor,
             SIGNAL(timeout()),
             SLOT(slotUpdateRegenerateFilling()));
 
     connect(this, SIGNAL(sigUpdateOnDirtyParent()),
             &m_d->dirtyParentUpdateCompressor, SLOT(start()));
 
     connect(&m_d->dirtyParentUpdateCompressor,
             SIGNAL(timeout()),
             SLOT(slotUpdateOnDirtyParent()));
 
     connect(&m_d->prefilterRecalculationCompressor,
             SIGNAL(timeout()),
             SLOT(slotRecalculatePrefilteredImage()));
 
 
     m_d->updateCompressor.moveToThread(qApp->thread());
 }
 
 KisColorizeMask::~KisColorizeMask()
 {
 }
 
 KisColorizeMask::KisColorizeMask(const KisColorizeMask& rhs)
     : KisEffectMask(rhs),
       m_d(new Private(*rhs.m_d, this))
 {
     connect(&m_d->updateCompressor,
             SIGNAL(timeout()),
             SLOT(slotUpdateRegenerateFilling()));
 
     connect(this, SIGNAL(sigUpdateOnDirtyParent()),
             &m_d->dirtyParentUpdateCompressor, SLOT(start()));
 
     connect(&m_d->dirtyParentUpdateCompressor,
             SIGNAL(timeout()),
             SLOT(slotUpdateOnDirtyParent()));
 
     m_d->updateCompressor.moveToThread(qApp->thread());
 }
 
 void KisColorizeMask::initializeCompositeOp()
 {
     KisLayerSP parentLayer(qobject_cast<KisLayer*>(parent().data()));
     if (!parentLayer || !parentLayer->original()) return;
 
     KisImageSP image = parentLayer->image();
     if (!image) return;
 
     const qreal samplePortion = 0.1;
     const qreal alphaPortion =
         KritaUtils::estimatePortionOfTransparentPixels(parentLayer->original(),
                                                        image->bounds(),
                                                        samplePortion);
 
     setCompositeOpId(alphaPortion > 0.3 ? COMPOSITE_BEHIND : COMPOSITE_MULT);
 }
 
 const KoColorSpace* KisColorizeMask::colorSpace() const
 {
     return m_d->fakePaintDevice->colorSpace();
 }
 
 struct SetKeyStrokesColorSpaceCommand : public KUndo2Command {
     SetKeyStrokesColorSpaceCommand(const KoColorSpace *dstCS,
                                    KoColorConversionTransformation::Intent renderingIntent,
                                    KoColorConversionTransformation::ConversionFlags conversionFlags,
                                    QList<KeyStroke> *list,
                                    KisColorizeMaskSP node)
         : m_dstCS(dstCS),
           m_renderingIntent(renderingIntent),
           m_conversionFlags(conversionFlags),
           m_list(list),
           m_node(node) {}
 
     void undo() override {
         KIS_ASSERT_RECOVER_RETURN(m_list->size() == m_oldColors.size());
 
         for (int i = 0; i < m_list->size(); i++) {
             (*m_list)[i].color = m_oldColors[i];
         }
 
         m_node->setNeedsUpdate(true);
     }
 
     void redo() override {
         if (m_oldColors.isEmpty()) {
             Q_FOREACH(const KeyStroke &stroke, *m_list) {
                 m_oldColors << stroke.color;
                 m_newColors << stroke.color;
                 m_newColors.last().convertTo(m_dstCS, m_renderingIntent, m_conversionFlags);
             }
         }
 
         KIS_ASSERT_RECOVER_RETURN(m_list->size() == m_newColors.size());
 
         for (int i = 0; i < m_list->size(); i++) {
             (*m_list)[i].color = m_newColors[i];
         }
 
         m_node->setNeedsUpdate(true);
     }
 
 private:
     QVector<KoColor> m_oldColors;
     QVector<KoColor> m_newColors;
 
     const KoColorSpace *m_dstCS;
     KoColorConversionTransformation::Intent m_renderingIntent;
     KoColorConversionTransformation::ConversionFlags m_conversionFlags;
     QList<KeyStroke> *m_list;
     KisColorizeMaskSP m_node;
 };
 
 
 void KisColorizeMask::setProfile(const KoColorProfile *profile)
 {
     // WARNING: there is no undo information, used only while loading!
 
     m_d->fakePaintDevice->setProfile(profile);
     m_d->coloringProjection->setProfile(profile);
 
     for (auto stroke : m_d->keyStrokes) {
         stroke.color.setProfile(profile);
     }
 }
 
 KUndo2Command* KisColorizeMask::setColorSpace(const KoColorSpace * dstColorSpace,
                                               KoColorConversionTransformation::Intent renderingIntent,
                                               KoColorConversionTransformation::ConversionFlags conversionFlags)
 {
     using namespace KisCommandUtils;
 
     CompositeCommand *composite = new CompositeCommand();
 
     composite->addCommand(m_d->fakePaintDevice->convertTo(dstColorSpace, renderingIntent, conversionFlags));
     composite->addCommand(m_d->coloringProjection->convertTo(dstColorSpace, renderingIntent, conversionFlags));
 
     KUndo2Command *strokesConversionCommand =
         new SetKeyStrokesColorSpaceCommand(
             dstColorSpace, renderingIntent, conversionFlags,
             &m_d->keyStrokes, KisColorizeMaskSP(this));
     strokesConversionCommand->redo();
 
     composite->addCommand(new SkipFirstRedoWrapper(strokesConversionCommand));
 
     return composite;
 }
 
 bool KisColorizeMask::needsUpdate() const
 {
     return m_d->needsUpdate;
 }
 
 void KisColorizeMask::setNeedsUpdate(bool value)
 {
     m_d->setNeedsUpdateImpl(value, true);
 }
 
 void KisColorizeMask::Private::setNeedsUpdateImpl(bool value, bool requestedByUser)
 {
     if (value != needsUpdate) {
         needsUpdate = value;
         q->baseNodeChangedCallback();
 
         if (!value && requestedByUser) {
             updateCompressor.start();
         }
     }
 }
 
 void KisColorizeMask::slotUpdateRegenerateFilling(bool prefilterOnly)
 {
     KisPaintDeviceSP src = parent()->original();
     KIS_ASSERT_RECOVER_RETURN(src);
 
     const bool filteredSourceValid = m_d->filteredSourceValid(src);
     m_d->originalSequenceNumber = src->sequenceNumber();
     m_d->filteringDirty = false;
 
     if (!prefilterOnly) {
         m_d->coloringProjection->clear();
     }
 
     KisLayerSP parentLayer(qobject_cast<KisLayer*>(parent().data()));
     if (!parentLayer) return;
 
     KisImageSP image = parentLayer->image();
     if (image) {
         m_d->updateIsRunning = true;
 
         QRect fillBounds;
 
         if (m_d->limitToDeviceBounds) {
             fillBounds |= src->exactBounds();
             Q_FOREACH (const KeyStroke &stroke, m_d->keyStrokes) {
                 fillBounds |= stroke.dev->exactBounds();
             }
             fillBounds &= image->bounds();
         } else {
             fillBounds = image->bounds();
         }
 
         m_d->filteredDeviceBounds = fillBounds;
 
         KisColorizeStrokeStrategy *strategy =
             new KisColorizeStrokeStrategy(src,
                                           m_d->coloringProjection,
                                           m_d->filteredSource,
                                           filteredSourceValid,
                                           fillBounds,
                                           this,
                                           prefilterOnly);
 
         strategy->setFilteringOptions(m_d->filteringOptions);
 
         Q_FOREACH (const KeyStroke &stroke, m_d->keyStrokes) {
             const KoColor color =
                 !stroke.isTransparent ?
                 stroke.color :
                 KoColor(Qt::transparent, stroke.color.colorSpace());
 
             strategy->addKeyStroke(stroke.dev, color);
         }
 
         m_d->extentBeforeUpdateStart.push(extent());
 
         connect(strategy, SIGNAL(sigFinished(bool)), SLOT(slotRegenerationFinished(bool)));
         connect(strategy, SIGNAL(sigCancelled()), SLOT(slotRegenerationCancelled()));
         KisStrokeId id = image->startStroke(strategy);
         image->endStroke(id);
     }
 }
 
 void KisColorizeMask::slotUpdateOnDirtyParent()
 {
-    KIS_ASSERT_RECOVER_RETURN(parent());
+    if (!parent()) {
+        // When the colorize mask is being merged,
+        // the update is performed for all the layers,
+        // so the invisible areas around the canvas are included in the merged layer.
+        // Colorize Mask gets the info that its parent is "dirty" (needs updating),
+        // but when it arrives, the parent doesn't exists anymore and is set to null.
+        // Colorize Mask doesn't work outside of the canvas anyway (at least in time of writing).
+        return;
+    }
     KisPaintDeviceSP src = parent()->original();
     KIS_ASSERT_RECOVER_RETURN(src);
 
     if (!m_d->filteredSourceValid(src)) {
         const QRect &oldExtent = extent();
 
         m_d->setNeedsUpdateImpl(true, false);
         m_d->filteringDirty = true;
 
         setDirty(oldExtent | extent());
     }
 }
 
 void KisColorizeMask::slotRecalculatePrefilteredImage()
 {
     slotUpdateRegenerateFilling(true);
 }
 
 void KisColorizeMask::slotRegenerationFinished(bool prefilterOnly)
 {
     m_d->updateIsRunning = false;
 
     if (!prefilterOnly) {
         m_d->setNeedsUpdateImpl(false, false);
     }
 
     QRect oldExtent;
 
     if (!m_d->extentBeforeUpdateStart.isEmpty()) {
         oldExtent = m_d->extentBeforeUpdateStart.pop();
     } else {
         KIS_SAFE_ASSERT_RECOVER_NOOP(!m_d->extentBeforeUpdateStart.isEmpty()); // always fail!
     }
 
     setDirty(oldExtent | extent());
 }
 
 void KisColorizeMask::slotRegenerationCancelled()
 {
     slotRegenerationFinished(true);
 }
 
 KisBaseNode::PropertyList KisColorizeMask::sectionModelProperties() const
 {
     KisBaseNode::PropertyList l = KisMask::sectionModelProperties();
     l << KisLayerPropertiesIcons::getProperty(KisLayerPropertiesIcons::colorizeNeedsUpdate, needsUpdate());
     l << KisLayerPropertiesIcons::getProperty(KisLayerPropertiesIcons::colorizeEditKeyStrokes, showKeyStrokes());
     l << KisLayerPropertiesIcons::getProperty(KisLayerPropertiesIcons::colorizeShowColoring, showColoring());
 
     return l;
 }
 
 void KisColorizeMask::setSectionModelProperties(const KisBaseNode::PropertyList &properties)
 {
     KisMask::setSectionModelProperties(properties);
 
     Q_FOREACH (const KisBaseNode::Property &property, properties) {
         if (property.id == KisLayerPropertiesIcons::colorizeNeedsUpdate.id()) {
             if (m_d->needsUpdate && m_d->needsUpdate != property.state.toBool()) {
                 setNeedsUpdate(property.state.toBool());
             }
         }
         if (property.id == KisLayerPropertiesIcons::colorizeEditKeyStrokes.id()) {
             if (m_d->showKeyStrokes != property.state.toBool()) {
                 setShowKeyStrokes(property.state.toBool());
             }
         }
         if (property.id == KisLayerPropertiesIcons::colorizeShowColoring.id()) {
             if (m_d->showColoring != property.state.toBool()) {
                 setShowColoring(property.state.toBool());
             }
         }
     }
 }
 
 KisPaintDeviceSP KisColorizeMask::paintDevice() const
 {
     return m_d->showKeyStrokes && !m_d->updateIsRunning ? m_d->fakePaintDevice : KisPaintDeviceSP();
 }
 
 KisPaintDeviceSP KisColorizeMask::coloringProjection() const
 {
     return m_d->coloringProjection;
 }
 
 KisPaintDeviceSP KisColorizeMask::colorPickSourceDevice() const
 {
     return
         m_d->shouldShowColoring() && !m_d->coloringProjection->extent().isEmpty() ?
             m_d->coloringProjection : projection();
 }
 
 QIcon KisColorizeMask::icon() const
 {
     return KisIconUtils::loadIcon("colorizeMask");
 }
 
 
 bool KisColorizeMask::accept(KisNodeVisitor &v)
 {
     return v.visit(this);
 }
 
 void KisColorizeMask::accept(KisProcessingVisitor &visitor, KisUndoAdapter *undoAdapter)
 {
     return visitor.visit(this, undoAdapter);
 }
 
 bool KisColorizeMask::Private::shouldShowFilteredSource() const
 {
     return !updateIsRunning &&
             showKeyStrokes &&
             !filteringDirty &&
             filteredSource &&
             !filteredSource->extent().isEmpty();
 }
 
 bool KisColorizeMask::Private::shouldShowColoring() const
 {
     return !updateIsRunning &&
             showColoring &&
             coloringProjection;
 }
 
 QRect KisColorizeMask::decorateRect(KisPaintDeviceSP &src,
                                     KisPaintDeviceSP &dst,
                                     const QRect &rect,
                                     PositionToFilthy maskPos) const
 {
     Q_UNUSED(maskPos);
 
     if (maskPos == N_ABOVE_FILTHY) {
         // the source layer has changed, we should update the filtered cache!
 
         if (!m_d->filteringDirty) {
             emit sigUpdateOnDirtyParent();
         }
     }
 
     KIS_ASSERT(dst != src);
 
     // Draw the filling and the original layer
     {
         KisPainter gc(dst);
 
         if (m_d->shouldShowFilteredSource()) {
             const QRect drawRect = m_d->limitToDeviceBounds ? rect & m_d->filteredDeviceBounds : rect;
 
             gc.setOpacity(128);
             gc.bitBlt(drawRect.topLeft(), m_d->filteredSource, drawRect);
         } else {
             gc.setOpacity(255);
             gc.bitBlt(rect.topLeft(), src, rect);
         }
 
         if (m_d->shouldShowColoring()) {
 
             gc.setOpacity(opacity());
             gc.setCompositeOp(compositeOpId());
             gc.bitBlt(rect.topLeft(), m_d->coloringProjection, rect);
         }
     }
 
     // Draw the key strokes
     if (m_d->showKeyStrokes) {
         KisIndirectPaintingSupport::ReadLocker locker(this);
 
         KisSelectionSP selection = m_d->cachedSelection.getSelection();
         KisSelectionSP conversionSelection = m_d->cachedConversionSelection.getSelection();
         KisPixelSelectionSP tempSelection = conversionSelection->pixelSelection();
 
         KisPaintDeviceSP temporaryTarget = this->temporaryTarget();
         const bool isTemporaryTargetErasing = temporaryCompositeOp() == COMPOSITE_ERASE;
         const QRect temporaryExtent = temporaryTarget ? temporaryTarget->extent() : QRect();
 
 
         KisFillPainter gc(dst);
 
         QList<KeyStroke> extendedStrokes = m_d->keyStrokes;
 
         if (m_d->currentKeyStrokeDevice &&
             m_d->needAddCurrentKeyStroke &&
             !isTemporaryTargetErasing) {
 
             extendedStrokes << KeyStroke(m_d->currentKeyStrokeDevice, m_d->currentColor);
         }
 
         Q_FOREACH (const KeyStroke &stroke, extendedStrokes) {
             selection->pixelSelection()->makeCloneFromRough(stroke.dev, rect);
             gc.setSelection(selection);
 
             if (stroke.color == m_d->currentColor ||
                 (isTemporaryTargetErasing &&
                  temporaryExtent.intersects(selection->pixelSelection()->selectedRect()))) {
 
                 if (temporaryTarget) {
                     tempSelection->copyAlphaFrom(temporaryTarget, rect);
 
                     KisPainter selectionPainter(selection->pixelSelection());
                     setupTemporaryPainter(&selectionPainter);
                     selectionPainter.bitBlt(rect.topLeft(), tempSelection, rect);
                 }
             }
 
             gc.fillSelection(rect, stroke.color);
         }
 
         m_d->cachedSelection.putSelection(selection);
         m_d->cachedSelection.putSelection(conversionSelection);
     }
 
     return rect;
 }
 
 struct DeviceExtentPolicy
 {
     inline QRect operator() (const KisPaintDevice *dev) {
         return dev->extent();
     }
 };
 
 struct DeviceExactBoundsPolicy
 {
     inline QRect operator() (const KisPaintDevice *dev) {
         return dev->exactBounds();
     }
 };
 
 template <class DeviceMetricPolicy>
 QRect KisColorizeMask::calculateMaskBounds(DeviceMetricPolicy boundsPolicy) const
 {
     QRect rc;
 
     if (m_d->shouldShowFilteredSource()) {
         rc |= boundsPolicy(m_d->filteredSource);
     }
 
     if (m_d->shouldShowColoring()) {
         rc |= boundsPolicy(m_d->coloringProjection);
     }
 
     if (m_d->showKeyStrokes) {
         Q_FOREACH (const KeyStroke &stroke, m_d->keyStrokes) {
             rc |= boundsPolicy(stroke.dev);
         }
 
         KisIndirectPaintingSupport::ReadLocker locker(this);
 
         KisPaintDeviceSP temporaryTarget = this->temporaryTarget();
         if (temporaryTarget) {
             rc |= boundsPolicy(temporaryTarget);
         }
     }
 
     return rc;
 }
 
 
 QRect KisColorizeMask::extent() const
 {
     return calculateMaskBounds(DeviceExtentPolicy());
 }
 
 QRect KisColorizeMask::exactBounds() const
 {
     return calculateMaskBounds(DeviceExactBoundsPolicy());
 }
 
 QRect KisColorizeMask::nonDependentExtent() const
 {
     return extent();
 }
 
 KisImageSP KisColorizeMask::fetchImage() const
 {
     KisLayerSP parentLayer(qobject_cast<KisLayer*>(parent().data()));
     if (!parentLayer) return KisImageSP();
 
     return parentLayer->image();
 }
 
 void KisColorizeMask::setImage(KisImageWSP image)
 {
     KisDefaultBoundsSP bounds(new KisDefaultBounds(image));
 
     auto it = m_d->keyStrokes.begin();
     for(; it != m_d->keyStrokes.end(); ++it) {
         it->dev->setDefaultBounds(bounds);
     }
 
     m_d->coloringProjection->setDefaultBounds(bounds);
     m_d->fakePaintDevice->setDefaultBounds(bounds);
     m_d->filteredSource->setDefaultBounds(bounds);
 }
 
 void KisColorizeMask::setCurrentColor(const KoColor &_color)
 {
     KoColor color = _color;
     color.convertTo(colorSpace());
 
     WriteLocker locker(this);
 
     m_d->setNeedsUpdateImpl(true, false);
 
     QList<KeyStroke>::const_iterator it =
         std::find_if(m_d->keyStrokes.constBegin(),
                      m_d->keyStrokes.constEnd(),
                      [color] (const KeyStroke &s) {
                          return s.color == color;
                      });
 
     KisPaintDeviceSP activeDevice;
     bool newKeyStroke = false;
 
     if (it == m_d->keyStrokes.constEnd()) {
         activeDevice = new KisPaintDevice(KoColorSpaceRegistry::instance()->alpha8());
         activeDevice->setParentNode(this);
         activeDevice->setDefaultBounds(KisDefaultBoundsBaseSP(new KisDefaultBounds(fetchImage())));
         newKeyStroke = true;
     } else {
         activeDevice = it->dev;
     }
 
     m_d->currentColor = color;
     m_d->currentKeyStrokeDevice = activeDevice;
     m_d->needAddCurrentKeyStroke = newKeyStroke;
 }
 
 
 
 struct KeyStrokeAddRemoveCommand : public KisCommandUtils::FlipFlopCommand {
     KeyStrokeAddRemoveCommand(bool add, int index, KeyStroke stroke, QList<KeyStroke> *list, KisColorizeMaskSP node)
         : FlipFlopCommand(!add),
           m_index(index), m_stroke(stroke),
           m_list(list), m_node(node) {}
 
     void partA() override {
         m_list->insert(m_index, m_stroke);
         m_node->setNeedsUpdate(true);
         emit m_node->sigKeyStrokesListChanged();
     }
 
     void partB() override {
         KIS_ASSERT_RECOVER_RETURN((*m_list)[m_index] == m_stroke);
         m_list->removeAt(m_index);
         m_node->setNeedsUpdate(true);
         emit m_node->sigKeyStrokesListChanged();
     }
 
 private:
     int m_index;
     KeyStroke m_stroke;
     QList<KeyStroke> *m_list;
     KisColorizeMaskSP m_node;
 };
 
 void KisColorizeMask::mergeToLayer(KisNodeSP layer, KisPostExecutionUndoAdapter *undoAdapter, const KUndo2MagicString &transactionText,int timedID)
 {
     Q_UNUSED(layer);
 
     WriteLocker locker(this);
 
     KisPaintDeviceSP temporaryTarget = this->temporaryTarget();
     const bool isTemporaryTargetErasing = temporaryCompositeOp() == COMPOSITE_ERASE;
     const QRect temporaryExtent = temporaryTarget ? temporaryTarget->extent() : QRect();
 
     KisSavedMacroCommand *macro = undoAdapter->createMacro(transactionText);
     KisMacroBasedUndoStore store(macro);
     KisPostExecutionUndoAdapter fakeUndoAdapter(&store, undoAdapter->strokesFacade());
 
     /**
      * Add a new key stroke plane
      */
     if (m_d->needAddCurrentKeyStroke && !isTemporaryTargetErasing) {
         KeyStroke key(m_d->currentKeyStrokeDevice, m_d->currentColor);
 
         KUndo2Command *cmd =
             new KeyStrokeAddRemoveCommand(
                 true, m_d->keyStrokes.size(), key, &m_d->keyStrokes, KisColorizeMaskSP(this));
         cmd->redo();
         fakeUndoAdapter.addCommand(toQShared(cmd));
     }
 
     /**
      * When erasing, the brush affects all the key strokes, not only
      * the current one.
      */
     if (!isTemporaryTargetErasing) {
         mergeToLayerImpl(m_d->currentKeyStrokeDevice, &fakeUndoAdapter, transactionText, timedID, false);
     } else {
         Q_FOREACH (const KeyStroke &stroke, m_d->keyStrokes) {
             if (temporaryExtent.intersects(stroke.dev->extent())) {
                 mergeToLayerImpl(stroke.dev, &fakeUndoAdapter, transactionText, timedID, false);
             }
         }
     }
 
     mergeToLayerImpl(m_d->fakePaintDevice, &fakeUndoAdapter, transactionText, timedID, false);
 
     m_d->currentKeyStrokeDevice = 0;
     m_d->currentColor = KoColor();
     releaseResources();
 
     /**
      * Try removing the key strokes that has been completely erased
      */
     if (isTemporaryTargetErasing) {
         for (int index = 0; index < m_d->keyStrokes.size(); /*noop*/) {
             const KeyStroke &stroke = m_d->keyStrokes[index];
 
             if (stroke.dev->exactBounds().isEmpty()) {
                 KUndo2Command *cmd =
                     new KeyStrokeAddRemoveCommand(
                         false, index, stroke, &m_d->keyStrokes, KisColorizeMaskSP(this));
 
                 cmd->redo();
                 fakeUndoAdapter.addCommand(toQShared(cmd));
 
             } else {
                 index++;
             }
         }
     }
 
     undoAdapter->addMacro(macro);
 }
 
 void KisColorizeMask::writeMergeData(KisPainter *painter, KisPaintDeviceSP src)
 {
     const KoColorSpace *alpha8 = KoColorSpaceRegistry::instance()->alpha8();
     const bool nonAlphaDst = !(*painter->device()->colorSpace() == *alpha8);
 
     if (nonAlphaDst) {
         Q_FOREACH (const QRect &rc, src->region().rects()) {
             painter->bitBlt(rc.topLeft(), src, rc);
         }
     } else {
         KisSelectionSP conversionSelection = m_d->cachedConversionSelection.getSelection();
         KisPixelSelectionSP tempSelection = conversionSelection->pixelSelection();
 
         Q_FOREACH (const QRect &rc, src->region().rects()) {
             tempSelection->copyAlphaFrom(src, rc);
             painter->bitBlt(rc.topLeft(), tempSelection, rc);
         }
         m_d->cachedSelection.putSelection(conversionSelection);
     }
 }
 
 bool KisColorizeMask::supportsNonIndirectPainting() const
 {
     return false;
 }
 
 bool KisColorizeMask::showColoring() const
 {
     return m_d->showColoring;
 }
 
 void KisColorizeMask::setShowColoring(bool value)
 {
     QRect savedExtent;
     if (m_d->showColoring && !value) {
         savedExtent = extent();
     }
 
     m_d->showColoring = value;
     baseNodeChangedCallback();
 
     if (!savedExtent.isEmpty()) {
         setDirty(savedExtent);
     }
 }
 
 bool KisColorizeMask::showKeyStrokes() const
 {
     return m_d->showKeyStrokes;
 }
 
 void KisColorizeMask::setShowKeyStrokes(bool value)
 {
     QRect savedExtent;
     if (m_d->showKeyStrokes && !value) {
         savedExtent = extent();
     }
 
     m_d->showKeyStrokes = value;
     baseNodeChangedCallback();
 
     if (!savedExtent.isEmpty()) {
         setDirty(savedExtent);
     }
 
     regeneratePrefilteredDeviceIfNeeded();
 }
 
 KisColorizeMask::KeyStrokeColors KisColorizeMask::keyStrokesColors() const
 {
     KeyStrokeColors colors;
 
     // TODO: thread safety!
     for (int i = 0; i < m_d->keyStrokes.size(); i++) {
         colors.colors << m_d->keyStrokes[i].color;
 
         if (m_d->keyStrokes[i].isTransparent) {
             colors.transparentIndex = i;
         }
     }
 
     return colors;
 }
 
 struct SetKeyStrokeColorsCommand : public KUndo2Command {
     SetKeyStrokeColorsCommand(const QList<KeyStroke> newList, QList<KeyStroke> *list, KisColorizeMaskSP node)
         : m_newList(newList),
           m_oldList(*list),
           m_list(list),
           m_node(node) {}
 
     void redo() override {
         *m_list = m_newList;
 
         m_node->setNeedsUpdate(true);
         emit m_node->sigKeyStrokesListChanged();
         m_node->setDirty();
     }
 
     void undo() override {
         *m_list = m_oldList;
 
         m_node->setNeedsUpdate(true);
         emit m_node->sigKeyStrokesListChanged();
         m_node->setDirty();
     }
 
 private:
     QList<KeyStroke> m_newList;
     QList<KeyStroke> m_oldList;
     QList<KeyStroke> *m_list;
     KisColorizeMaskSP m_node;
 };
 
 void KisColorizeMask::setKeyStrokesColors(KeyStrokeColors colors)
 {
     KIS_ASSERT_RECOVER_RETURN(colors.colors.size() == m_d->keyStrokes.size());
 
     QList<KeyStroke> newList = m_d->keyStrokes;
 
     for (int i = 0; i < newList.size(); i++) {
         newList[i].color = colors.colors[i];
         newList[i].color.convertTo(colorSpace());
         newList[i].isTransparent = colors.transparentIndex == i;
     }
 
     KisProcessingApplicator applicator(fetchImage(), KisNodeSP(this),
                                        KisProcessingApplicator::NONE,
                                        KisImageSignalVector(),
                                        kundo2_i18n("Change Key Stroke Color"));
     applicator.applyCommand(
         new SetKeyStrokeColorsCommand(
             newList, &m_d->keyStrokes, KisColorizeMaskSP(this)));
 
     applicator.end();
 }
 
 void KisColorizeMask::removeKeyStroke(const KoColor &_color)
 {
     KoColor color = _color;
     color.convertTo(colorSpace());
 
     QList<KeyStroke>::iterator it =
         std::find_if(m_d->keyStrokes.begin(),
                      m_d->keyStrokes.end(),
                      [color] (const KeyStroke &s) {
                          return s.color == color;
                      });
 
     KIS_SAFE_ASSERT_RECOVER_RETURN(it != m_d->keyStrokes.end());
 
     const int index = it - m_d->keyStrokes.begin();
 
     KisProcessingApplicator applicator(KisImageWSP(fetchImage()), KisNodeSP(this),
                                        KisProcessingApplicator::NONE,
                                        KisImageSignalVector(),
                                        kundo2_i18n("Remove Key Stroke"));
     applicator.applyCommand(
         new KeyStrokeAddRemoveCommand(
             false, index, *it, &m_d->keyStrokes, KisColorizeMaskSP(this)));
 
     applicator.end();
 }
 
 
 QVector<KisPaintDeviceSP> KisColorizeMask::allPaintDevices() const
 {
     QVector<KisPaintDeviceSP> devices;
 
     Q_FOREACH (const KeyStroke &stroke, m_d->keyStrokes) {
         devices << stroke.dev;
     }
 
     devices << m_d->coloringProjection;
     devices << m_d->fakePaintDevice;
 
     return devices;
 }
 
 void KisColorizeMask::resetCache()
 {
     m_d->filteredSource->clear();
     m_d->originalSequenceNumber = -1;
     m_d->filteringDirty = true;
 
     rerenderFakePaintDevice();
     slotUpdateRegenerateFilling(true);
 }
 
 void KisColorizeMask::setUseEdgeDetection(bool value)
 {
     m_d->filteringOptions.useEdgeDetection = value;
     m_d->filteringDirty = true;
     setNeedsUpdate(true);
 }
 
 bool KisColorizeMask::useEdgeDetection() const
 {
     return m_d->filteringOptions.useEdgeDetection;
 }
 
 void KisColorizeMask::setEdgeDetectionSize(qreal value)
 {
     m_d->filteringOptions.edgeDetectionSize = value;
     m_d->filteringDirty = true;
     setNeedsUpdate(true);
 }
 
 qreal KisColorizeMask::edgeDetectionSize() const
 {
     return m_d->filteringOptions.edgeDetectionSize;
 }
 
 void KisColorizeMask::setFuzzyRadius(qreal value)
 {
     m_d->filteringOptions.fuzzyRadius = value;
     m_d->filteringDirty = true;
     setNeedsUpdate(true);
 }
 
 qreal KisColorizeMask::fuzzyRadius() const
 {
     return m_d->filteringOptions.fuzzyRadius;
 }
 
 void KisColorizeMask::setCleanUpAmount(qreal value)
 {
     m_d->filteringOptions.cleanUpAmount = value;
     setNeedsUpdate(true);
 }
 
 qreal KisColorizeMask::cleanUpAmount() const
 {
     return m_d->filteringOptions.cleanUpAmount;
 }
 
 void KisColorizeMask::setLimitToDeviceBounds(bool value)
 {
     m_d->limitToDeviceBounds = value;
     m_d->filteringDirty = true;
     setNeedsUpdate(true);
 }
 
 bool KisColorizeMask::limitToDeviceBounds() const
 {
     return m_d->limitToDeviceBounds;
 }
 
 void KisColorizeMask::rerenderFakePaintDevice()
 {
     m_d->fakePaintDevice->clear();
     KisFillPainter gc(m_d->fakePaintDevice);
 
     KisSelectionSP selection = m_d->cachedSelection.getSelection();
 
     Q_FOREACH (const KeyStroke &stroke, m_d->keyStrokes) {
         const QRect rect = stroke.dev->extent();
 
         selection->pixelSelection()->makeCloneFromRough(stroke.dev, rect);
         gc.setSelection(selection);
         gc.fillSelection(rect, stroke.color);
     }
 
     m_d->cachedSelection.putSelection(selection);
 }
 
 void KisColorizeMask::testingAddKeyStroke(KisPaintDeviceSP dev, const KoColor &color, bool isTransparent)
 {
     m_d->keyStrokes << KeyStroke(dev, color, isTransparent);
 }
 
 void KisColorizeMask::testingRegenerateMask()
 {
     slotUpdateRegenerateFilling();
     m_d->updateIsRunning = false;
 }
 
 KisPaintDeviceSP KisColorizeMask::testingFilteredSource() const
 {
     return m_d->filteredSource;
 }
 
 QList<KeyStroke> KisColorizeMask::fetchKeyStrokesDirect() const
 {
     return m_d->keyStrokes;
 }
 
 void KisColorizeMask::setKeyStrokesDirect(const QList<KisLazyFillTools::KeyStroke> &strokes)
 {
     m_d->keyStrokes = strokes;
 
     for (auto it = m_d->keyStrokes.begin(); it != m_d->keyStrokes.end(); ++it) {
         it->dev->setParentNode(this);
     }
 
     KisImageSP image = fetchImage();
     KIS_SAFE_ASSERT_RECOVER_RETURN(image);
     setImage(image);
 }
 
 qint32 KisColorizeMask::x() const
 {
     return m_d->offset.x();
 }
 
 qint32 KisColorizeMask::y() const
 {
     return m_d->offset.y();
 }
 
 void KisColorizeMask::setX(qint32 x)
 {
     const QPoint oldOffset = m_d->offset;
     m_d->offset.rx() = x;
     moveAllInternalDevices(m_d->offset - oldOffset);
 }
 
 void KisColorizeMask::setY(qint32 y)
 {
     const QPoint oldOffset = m_d->offset;
     m_d->offset.ry() = y;
     moveAllInternalDevices(m_d->offset - oldOffset);
 }
 
 KisPaintDeviceList KisColorizeMask::getLodCapableDevices() const
 {
     KisPaintDeviceList list;
 
     auto it = m_d->keyStrokes.begin();
     for(; it != m_d->keyStrokes.end(); ++it) {
         list << it->dev;
     }
 
     list << m_d->coloringProjection;
     list << m_d->fakePaintDevice;
     list << m_d->filteredSource;
 
     return list;
 }
 
 void KisColorizeMask::regeneratePrefilteredDeviceIfNeeded()
 {
     if (!parent()) return;
 
     KisPaintDeviceSP src = parent()->original();
     KIS_ASSERT_RECOVER_RETURN(src);
 
     if (!m_d->filteredSourceValid(src)) {
         // update the prefiltered source if needed
         slotUpdateRegenerateFilling(true);
     }
 }
 
 void KisColorizeMask::moveAllInternalDevices(const QPoint &diff)
 {
     QVector<KisPaintDeviceSP> devices = allPaintDevices();
 
     Q_FOREACH (KisPaintDeviceSP dev, devices) {
         dev->moveTo(dev->offset() + diff);
     }
 }