diff --git a/app/src/importlayersdialog.cpp b/app/src/importlayersdialog.cpp
index f303072f0..35ae3f71b 100644
--- a/app/src/importlayersdialog.cpp
+++ b/app/src/importlayersdialog.cpp
@@ -27,6 +27,7 @@ GNU General Public License for more details.
 #include "soundmanager.h"
 #include "layer.h"
 #include "layersound.h"
+#include "layervector.h"
 #include "soundclip.h"
 
 
@@ -83,29 +84,43 @@ void ImportLayersDialog::importLayers()
     int currentFrame = mEditor->currentFrame();
     Q_ASSERT(ui->lwLayers->count() == mImportObject->getLayerCount());
 
-    for (int i = 0; i < ui->lwLayers->count(); i++ )
+    QMap<int, int> importedColors;
+
+    for (const QListWidgetItem* item : ui->lwLayers->selectedItems())
     {
-        QListWidgetItem* item = ui->lwLayers->item(i);
-        if (item->isSelected())
-        {
-            int layerId = item->data(Qt::UserRole).toInt();
+        mImportLayer = mImportObject->takeLayer(item->data(Qt::UserRole).toInt());
+        mImportLayer->setName(mEditor->layers()->nameSuggestLayer(item->text()));
+        loadKeyFrames(mImportLayer); // all keyframes of this layer must be in memory
 
-            mImportLayer = mImportObject->takeLayer(layerId);
-            mImportLayer->setName(mEditor->layers()->nameSuggestLayer(item->text()));
-            loadKeyFrames(mImportLayer); // all keyframes of this layer must be in memory
+        object->addLayer(mImportLayer);
 
-            object->addLayer(mImportLayer);
+        if (mImportLayer->type() == Layer::VECTOR)
+        {
+            LayerVector* layerVector = static_cast<LayerVector*>(mImportLayer);
+            for (int i = 0; i < mImportObject->getColorCount(); i++) {
+                if (!layerVector->usesColor(i)) {
+                    continue;
+                }
+
+                if (!importedColors.contains(i)) {
+                    const ColorRef color = mImportObject->getColor(i);
+                    object->addColor(color);
+                    importedColors[i] = object->getColorCount() - 1;
+                }
+
+                layerVector->moveColor(i, importedColors[i]);
+            }
+        }
 
-            if (mImportLayer->type() == Layer::SOUND)
+        if (mImportLayer->type() == Layer::SOUND)
+        {
+            LayerSound* layerSound = static_cast<LayerSound*>(mImportLayer);
+            layerSound->foreachKeyFrame([this](KeyFrame* key)
             {
-                LayerSound* layerSound = static_cast<LayerSound*>(mImportLayer);
-                layerSound->foreachKeyFrame([this](KeyFrame* key)
-                {
-                    SoundClip* clip = dynamic_cast<SoundClip*>(key);
-                    Status st = mEditor->sound()->loadSound(clip, clip->fileName());
-                    Q_ASSERT(st.ok());
-                });
-            }
+                SoundClip* clip = dynamic_cast<SoundClip*>(key);
+                Status st = mEditor->sound()->loadSound(clip, clip->fileName());
+                Q_ASSERT(st.ok());
+            });
         }
     }
     mEditor->object()->modification();
diff --git a/core_lib/src/canvaspainter.cpp b/core_lib/src/canvaspainter.cpp
index f03ae616f..24529ec38 100644
--- a/core_lib/src/canvaspainter.cpp
+++ b/core_lib/src/canvaspainter.cpp
@@ -251,7 +251,7 @@ void CanvasPainter::paintVectorOnionSkinFrame(QPainter& painter, const QRect& bl
     QPainter onionSkinPainter;
     initializePainter(onionSkinPainter, mOnionSkinPixmap, blitRect);
 
-    vectorImage->paintImage(onionSkinPainter, mOptions.bOutlines, mOptions.bThinLines, mOptions.bAntiAlias);
+    vectorImage->paintImage(onionSkinPainter, *mObject, mOptions.bOutlines, mOptions.bThinLines, mOptions.bAntiAlias);
     paintOnionSkinFrame(painter, onionSkinPainter, nFrame, colorize, vectorImage->getOpacity());
 }
 
@@ -344,7 +344,7 @@ void CanvasPainter::paintCurrentVectorFrame(QPainter& painter, const QRect& blit
     const bool isDrawing = mTiledBuffer->isValid();
 
     // Paint existing vector image to the painter
-    vectorImage->paintImage(currentVectorPainter, mOptions.bOutlines, mOptions.bThinLines, mOptions.bAntiAlias);
+    vectorImage->paintImage(currentVectorPainter, *mObject, mOptions.bOutlines, mOptions.bThinLines, mOptions.bAntiAlias);
 
     if (isCurrentLayer) {
         if (isDrawing) {
diff --git a/core_lib/src/graphics/vector/beziercurve.cpp b/core_lib/src/graphics/vector/beziercurve.cpp
index 97c2a79d6..ebfe27eea 100644
--- a/core_lib/src/graphics/vector/beziercurve.cpp
+++ b/core_lib/src/graphics/vector/beziercurve.cpp
@@ -34,7 +34,7 @@ BezierCurve::BezierCurve()
 BezierCurve::BezierCurve(const QList<QPointF>& pointList, bool smooth)
 {
     QList<qreal> pressureList;
-	for (int i = 0; i < pointList.size(); i++)
+    for (int i = 0; i < pointList.size(); i++)
     {
         pressureList << 0.5; // default pressure
     }
@@ -297,13 +297,13 @@ BezierCurve BezierCurve::transformed(QTransform transformation) const
     if (isSelected(-1)) { newOrigin =  transformation.map(newOrigin); }
     transformedCurve.setOrigin( newOrigin );
     for(int i=0; i< vertex.size(); i++) {
-    	QPointF newC1 = c1.at(i);
-    	QPointF newC2 = c2.at(i);
-    	QPointF newVertex = vertex.at(i);
-    	if (isSelected(i-1)) { newC1 = transformation.map(newC1); }
-    	if (isSelected(i)) { newC2 = transformation.map(newC2);  newVertex = transformation.map(newVertex); }
-    	transformedCurve.appendCubic( newC1, newC2, newVertex, pressure.at(i) );
-    	if (isSelected(i)) { transformedCurve.setSelected(i, true); }
+        QPointF newC1 = c1.at(i);
+        QPointF newC2 = c2.at(i);
+        QPointF newVertex = vertex.at(i);
+        if (isSelected(i-1)) { newC1 = transformation.map(newC1); }
+        if (isSelected(i)) { newC2 = transformation.map(newC2);  newVertex = transformation.map(newVertex); }
+        transformedCurve.appendCubic( newC1, newC2, newVertex, pressure.at(i) );
+        if (isSelected(i)) { transformedCurve.setSelected(i, true); }
     }
     transformedCurve.setWidth( width);
     transformedCurve.setVariableWidth( variableWidth );
@@ -429,9 +429,9 @@ void BezierCurve::removeVertex(int i)
     }
 }
 
-void BezierCurve::drawPath(QPainter& painter, Object* object, QTransform transformation, bool simplified, bool showThinLines )
+void BezierCurve::drawPath(QPainter& painter, const Object& object, QTransform transformation, bool simplified, bool showThinLines )
 {
-    QColor color = object->getColor(colorNumber).color;
+    QColor color = object.getColor(colorNumber).color;
 
     BezierCurve myCurve;
     if (isPartlySelected()) { myCurve = (transformed(transformation)); }
@@ -869,7 +869,7 @@ bool BezierCurve::findIntersection(BezierCurve curve1, int i1, BezierCurve curve
         //if (L2.intersect(L1, intersection) == QLineF::BoundedIntersection) {
         //qDebug() << "                   FOUND rectangle intersection ";
         //if (intersectionPoint != curve1.getVertex(i1-1) && intersectionPoint != curve1.getVertex(i1)) {
-        //	qDebug() << "                   it's not one of the points ";
+        //    qDebug() << "                   it's not one of the points ";
         // find the cubic intersection
         int nSteps = 24;
         P1 = curve1.getVertex(i1-1);
diff --git a/core_lib/src/graphics/vector/beziercurve.h b/core_lib/src/graphics/vector/beziercurve.h
index 0f1b67f30..47297f57f 100644
--- a/core_lib/src/graphics/vector/beziercurve.h
+++ b/core_lib/src/graphics/vector/beziercurve.h
@@ -89,7 +89,7 @@ class BezierCurve
     QPainterPath getStrokedPath(qreal width, bool pressure);
     QRectF getBoundingRect();
 
-    void drawPath(QPainter& painter, Object* object, QTransform transformation, bool simplified, bool showThinLines );
+    void drawPath(QPainter& painter, const Object& object, QTransform transformation, bool simplified, bool showThinLines );
     void createCurve(const QList<QPointF>& pointList, const QList<qreal>& pressureList , bool smooth);
     void smoothCurve();
 
diff --git a/core_lib/src/graphics/vector/vectorimage.cpp b/core_lib/src/graphics/vector/vectorimage.cpp
index 9dfe0980c..061b36c2b 100644
--- a/core_lib/src/graphics/vector/vectorimage.cpp
+++ b/core_lib/src/graphics/vector/vectorimage.cpp
@@ -33,7 +33,6 @@ VectorImage::VectorImage()
 VectorImage::VectorImage(const VectorImage& v2) : KeyFrame(v2)
 {
     deselectAll();
-    mObject = v2.mObject;
     mCurves = v2.mCurves;
     mArea = v2.mArea;
     mOpacity = v2.mOpacity;
@@ -52,7 +51,6 @@ VectorImage& VectorImage::operator=(const VectorImage& a) {
 
     deselectAll();
     KeyFrame::operator=(a);
-    mObject = a.mObject;
     mCurves = a.mCurves;
     mArea = a.mArea;
     mOpacity = a.mOpacity;
@@ -1090,16 +1088,6 @@ void VectorImage::paste(VectorImage& vectorImage)
     modification();
 }
 
-/**
- * @brief VectorImage::getColor
- * @param colorNumber: the color number which is referred to in the palette
- * @return QColor
- */
-QColor VectorImage::getColor(int colorNumber)
-{
-    return mObject->getColor(colorNumber).color;
-}
-
 /**
  * @brief VectorImage::getColorNumber
  * @param point: The QPoint of the BezierArea
@@ -1194,11 +1182,13 @@ void VectorImage::moveColor(int start, int end)
 /**
  * @brief VectorImage::paintImage
  * @param painter: QPainter&
+ * @param object: const Object&
  * @param simplified: bool
  * @param showThinCurves: bool
  * @param antialiasing: bool
  */
 void VectorImage::paintImage(QPainter& painter,
+    const Object& object,
     bool simplified,
     bool showThinCurves,
     bool antialiasing)
@@ -1220,7 +1210,7 @@ void VectorImage::paintImage(QPainter& painter,
             updateArea(mArea[i]); // to do: if selected
 
             // --- fill areas ---- //
-            QColor color = getColor(mArea[i].mColorNumber);
+            QColor color = object.getColor(mArea[i].mColorNumber).color;
 
             painter.save();
             painter.setWorldMatrixEnabled(false);
@@ -1246,7 +1236,7 @@ void VectorImage::paintImage(QPainter& painter,
     // ---- draw curves ----
     for (BezierCurve curve : mCurves)
     {
-        curve.drawPath(painter, mObject, mSelectionTransformation, simplified, showThinCurves);
+        curve.drawPath(painter, object, mSelectionTransformation, simplified, showThinCurves);
         painter.setClipping(false);
     }
     painter.restore();
diff --git a/core_lib/src/graphics/vector/vectorimage.h b/core_lib/src/graphics/vector/vectorimage.h
index ec97458a5..8f9769deb 100644
--- a/core_lib/src/graphics/vector/vectorimage.h
+++ b/core_lib/src/graphics/vector/vectorimage.h
@@ -38,8 +38,6 @@ class VectorImage : public KeyFrame
 
     VectorImage* clone() const override;
 
-    void setObject(Object* pObj) { mObject = pObj; }
-
     bool read(QString filePath);
     Status write(QString filePath, QString format);
 
@@ -85,7 +83,6 @@ class VectorImage : public KeyFrame
 
     void paste(VectorImage&);
 
-    QColor getColor(int i);
     int  getColorNumber(QPointF point);
     bool usesColor(int index);
     void removeColor(int index);
@@ -93,7 +90,7 @@ class VectorImage : public KeyFrame
     bool isCurveVisible(int curve);
     void moveColor(int start, int end);
 
-    void paintImage(QPainter& painter, bool simplified, bool showThinCurves, bool antialiasing);
+    void paintImage(QPainter& painter, const Object& object, bool simplified, bool showThinCurves, bool antialiasing);
 
     void clear();
     void clean();
@@ -165,7 +162,6 @@ class VectorImage : public KeyFrame
 private:
     QList<BezierCurve> mCurves;
 
-    Object* mObject = nullptr;
     QRectF mSelectionRect;
     QTransform mSelectionTransformation;
     QSize mSize;
diff --git a/core_lib/src/managers/soundmanager.cpp b/core_lib/src/managers/soundmanager.cpp
index 655d51307..8bcc3843c 100644
--- a/core_lib/src/managers/soundmanager.cpp
+++ b/core_lib/src/managers/soundmanager.cpp
@@ -68,57 +68,6 @@ Status SoundManager::save(Object*)
     return Status::OK;
 }
 
-Status SoundManager::loadSound(Layer* soundLayer, int frameNumber, QString soundFilePath)
-{
-    Q_ASSERT(soundLayer);
-    if (soundLayer->type() != Layer::SOUND)
-    {
-        return Status::ERROR_INVALID_LAYER_TYPE;
-    }
-
-    if (frameNumber < 0)
-    {
-        return Status::ERROR_INVALID_FRAME_NUMBER;
-    }
-
-    if (!QFile::exists(soundFilePath))
-    {
-        return Status::FILE_NOT_FOUND;
-    }
-
-    KeyFrame* key = soundLayer->getKeyFrameAt(frameNumber);
-    if (key == nullptr)
-    {
-        key = new SoundClip;
-        soundLayer->addKeyFrame(frameNumber, key);
-    }
-
-    if (!key->fileName().isEmpty())
-    {
-        // file path should be empty.
-        // we can only load a audio clip to an empty key!
-        return Status::FAIL;
-    }
-
-    QString strCopyFile = soundLayer->object()->copyFileToDataFolder(soundFilePath);
-    Q_ASSERT(!strCopyFile.isEmpty());
-
-    QString sOriginalName = QFileInfo(soundFilePath).fileName();
-
-    SoundClip* soundClip = dynamic_cast<SoundClip*>(key);
-    soundClip->init(strCopyFile);
-    soundClip->setSoundClipName(sOriginalName);
-
-    Status st = createMediaPlayer(soundClip);
-    if (!st.ok())
-    {
-        delete soundClip;
-        return st;
-    }
-
-    return Status::OK;
-}
-
 Status SoundManager::loadSound(SoundClip* soundClip, QString strSoundFile)
 {
     Q_ASSERT(soundClip);
diff --git a/core_lib/src/managers/soundmanager.h b/core_lib/src/managers/soundmanager.h
index 31abc12d5..4085ad3b5 100644
--- a/core_lib/src/managers/soundmanager.h
+++ b/core_lib/src/managers/soundmanager.h
@@ -38,7 +38,6 @@ class SoundManager : public BaseManager
     Status load(Object*) override;
     Status save(Object*) override;
 
-    Status loadSound(Layer* soundLayer, int frameNumber, QString strSoundFile);
     Status loadSound(SoundClip* soundClip, QString strSoundFile);
     Status processSound(SoundClip* soundClip);
 
diff --git a/core_lib/src/structure/layer.cpp b/core_lib/src/structure/layer.cpp
index 1e5f43553..f272e5912 100644
--- a/core_lib/src/structure/layer.cpp
+++ b/core_lib/src/structure/layer.cpp
@@ -22,7 +22,6 @@ GNU General Public License for more details.
 #include <QPainter>
 #include <QDomElement>
 #include "keyframe.h"
-#include "object.h"
 
 // Used to sort the selected frames list
 bool sortAsc(int left, int right)
@@ -30,15 +29,14 @@ bool sortAsc(int left, int right)
     return left < right;
 }
 
-Layer::Layer(Object* object, LAYER_TYPE eType)
+Layer::Layer(int id, LAYER_TYPE eType)
 {
     Q_ASSERT(eType != UNDEFINED);
 
-    mObject = object;
     meType = eType;
     mName = QString(tr("Undefined Layer"));
 
-    mId = object->getUniqueLayerID();
+    mId = id;
 }
 
 Layer::~Layer()
@@ -51,13 +49,6 @@ Layer::~Layer()
     mKeyFrames.clear();
 }
 
-void Layer::setObject(Object* obj)
-{
-    Q_ASSERT(obj);
-    mObject = obj;
-    mId = mObject->getUniqueLayerID();
-}
-
 void Layer::foreachKeyFrame(std::function<void(KeyFrame*)> action) const
 {
     for (auto pair : mKeyFrames)
@@ -180,7 +171,7 @@ bool Layer::addNewKeyFrameAt(int position)
 {
     if (position <= 0) return false;
 
-    KeyFrame* key = createKeyFrame(position, mObject);
+    KeyFrame* key = createKeyFrame(position);
     return addKeyFrame(position, key);
 }
 
diff --git a/core_lib/src/structure/layer.h b/core_lib/src/structure/layer.h
index bbb857cf8..0e82e2b1d 100644
--- a/core_lib/src/structure/layer.h
+++ b/core_lib/src/structure/layer.h
@@ -28,11 +28,10 @@ class QMouseEvent;
 class QPainter;
 
 class KeyFrame;
-class Object;
 class TimeLineCells;
 class Status;
 
-#define ProgressCallback std::function<void()>
+typedef std::function<void()> ProgressCallback;
 
 class Layer : public QObject
 {
@@ -49,15 +48,13 @@ class Layer : public QObject
         CAMERA = 5,
     };
 
-    explicit Layer(Object*, LAYER_TYPE);
+    explicit Layer(int id, LAYER_TYPE eType);
     ~Layer() override;
 
     int id() const { return mId; }
+    void setId(int layerId) { mId = layerId; }
     LAYER_TYPE type() const { return meType; }
 
-    Object* object() const { return mObject; }
-    void setObject(Object* obj);
-
     void setName(QString name) { mName = name; }
     QString name() const { return mName; }
 
@@ -168,15 +165,13 @@ class Layer : public QObject
     void clearDirtyFrames() { mDirtyFrames.clear(); }
 
 protected:
-    void setId(int LayerId) { mId = LayerId; }
-    virtual KeyFrame* createKeyFrame(int position, Object*) = 0;
+    virtual KeyFrame* createKeyFrame(int position) = 0;
     bool loadKey(KeyFrame*);
 
 private:
     void removeFromSelectionList(int position);
 
     LAYER_TYPE meType = UNDEFINED;
-    Object*    mObject = nullptr;
     int        mId = 0;
     bool       mVisible = true;
     QString    mName;
diff --git a/core_lib/src/structure/layerbitmap.cpp b/core_lib/src/structure/layerbitmap.cpp
index 119464046..d5eb0cc62 100644
--- a/core_lib/src/structure/layerbitmap.cpp
+++ b/core_lib/src/structure/layerbitmap.cpp
@@ -23,7 +23,7 @@ GNU General Public License for more details.
 #include "bitmapimage.h"
 
 
-LayerBitmap::LayerBitmap(Object* object) : Layer(object, Layer::BITMAP)
+LayerBitmap::LayerBitmap(int id) : Layer(id, Layer::BITMAP)
 {
     setName(tr("Bitmap Layer"));
 }
@@ -99,7 +99,7 @@ Status LayerBitmap::saveKeyFrameFile(KeyFrame* keyframe, QString path)
     return Status::OK;
 }
 
-KeyFrame* LayerBitmap::createKeyFrame(int position, Object*)
+KeyFrame* LayerBitmap::createKeyFrame(int position)
 {
     BitmapImage* b = new BitmapImage;
     b->setPos(position);
diff --git a/core_lib/src/structure/layerbitmap.h b/core_lib/src/structure/layerbitmap.h
index 4865dd64a..8ae10fe1a 100644
--- a/core_lib/src/structure/layerbitmap.h
+++ b/core_lib/src/structure/layerbitmap.h
@@ -27,7 +27,7 @@ class LayerBitmap : public Layer
     Q_OBJECT
 
 public:
-    LayerBitmap(Object* object);
+    explicit LayerBitmap(int id);
     ~LayerBitmap() override;
 
     QDomElement createDomElement(QDomDocument& doc) const override;
@@ -42,7 +42,7 @@ class LayerBitmap : public Layer
 
 protected:
     Status saveKeyFrameFile(KeyFrame*, QString strPath) override;
-    KeyFrame* createKeyFrame(int position, Object*) override;
+    KeyFrame* createKeyFrame(int position) override;
 
 private:
     void loadImageAtFrame(QString strFilePath, QPoint topLeft, int frameNumber, qreal opacity);
diff --git a/core_lib/src/structure/layercamera.cpp b/core_lib/src/structure/layercamera.cpp
index c41507f5b..b072954e0 100644
--- a/core_lib/src/structure/layercamera.cpp
+++ b/core_lib/src/structure/layercamera.cpp
@@ -22,7 +22,7 @@ GNU General Public License for more details.
 #include "camera.h"
 #include "pencildef.h"
 
-LayerCamera::LayerCamera(Object* object) : Layer(object, Layer::CAMERA)
+LayerCamera::LayerCamera(int id) : Layer(id, Layer::CAMERA)
 {
     setName(tr("Camera Layer"));
 
@@ -539,7 +539,7 @@ Status LayerCamera::saveKeyFrameFile(KeyFrame*, QString)
     return Status::OK;
 }
 
-KeyFrame* LayerCamera::createKeyFrame(int position, Object*)
+KeyFrame* LayerCamera::createKeyFrame(int position)
 {
     Camera* c = new Camera;
     c->setPos(position);
diff --git a/core_lib/src/structure/layercamera.h b/core_lib/src/structure/layercamera.h
index 0ef4cc151..54773ecb6 100644
--- a/core_lib/src/structure/layercamera.h
+++ b/core_lib/src/structure/layercamera.h
@@ -29,7 +29,7 @@ class Camera;
 class LayerCamera : public Layer
 {
 public:
-    explicit LayerCamera(Object* object);
+    explicit LayerCamera(int id);
     ~LayerCamera() override;
 
     void loadImageAtFrame(int frame, qreal dx, qreal dy, qreal rotate, qreal scale, CameraEasingType easing, const QPointF& pathPoint, bool pathMoved);
@@ -70,7 +70,7 @@ class LayerCamera : public Layer
 
 protected:
     Status saveKeyFrameFile(KeyFrame*, QString path) override;
-    KeyFrame* createKeyFrame(int position, Object*) override;
+    KeyFrame* createKeyFrame(int position) override;
 
 private:
     void linearInterpolateTransform(Camera*);
diff --git a/core_lib/src/structure/layersound.cpp b/core_lib/src/structure/layersound.cpp
index 83b46bc50..c3c88751d 100644
--- a/core_lib/src/structure/layersound.cpp
+++ b/core_lib/src/structure/layersound.cpp
@@ -20,11 +20,10 @@ GNU General Public License for more details.
 #include <QMediaPlayer>
 #include <QFileInfo>
 #include <QDir>
-#include "object.h"
 #include "soundclip.h"
 
 
-LayerSound::LayerSound(Object* object) : Layer(object, Layer::SOUND)
+LayerSound::LayerSound(int id) : Layer(id, Layer::SOUND)
 {
     setName(tr("Sound Layer"));
 }
@@ -155,7 +154,7 @@ Status LayerSound::saveKeyFrameFile(KeyFrame* key, QString path)
     return Status::OK;
 }
 
-KeyFrame* LayerSound::createKeyFrame(int position, Object*)
+KeyFrame* LayerSound::createKeyFrame(int position)
 {
     SoundClip* s = new SoundClip;
     s->setPos(position);
diff --git a/core_lib/src/structure/layersound.h b/core_lib/src/structure/layersound.h
index 718c6fc38..ddcf8c6fa 100644
--- a/core_lib/src/structure/layersound.h
+++ b/core_lib/src/structure/layersound.h
@@ -27,7 +27,7 @@ class LayerSound : public Layer
     Q_OBJECT
 
 public:
-    LayerSound( Object* object );
+    explicit LayerSound(int id);
     ~LayerSound();
     QDomElement createDomElement(QDomDocument& doc) const override;
     void loadDomElement(const QDomElement& element, QString dataDirPath, ProgressCallback progressStep) override;
@@ -39,7 +39,7 @@ class LayerSound : public Layer
 
 protected:
     Status saveKeyFrameFile(KeyFrame*, QString path) override;
-    KeyFrame* createKeyFrame(int position, Object*) override;
+    KeyFrame* createKeyFrame(int position) override;
 };
 
 #endif
diff --git a/core_lib/src/structure/layervector.cpp b/core_lib/src/structure/layervector.cpp
index 57ea14443..3efd51e9f 100644
--- a/core_lib/src/structure/layervector.cpp
+++ b/core_lib/src/structure/layervector.cpp
@@ -22,7 +22,7 @@ GNU General Public License for more details.
 #include <QFileInfo>
 
 
-LayerVector::LayerVector(Object* object) : Layer(object, Layer::VECTOR)
+LayerVector::LayerVector(int id) : Layer(id, Layer::VECTOR)
 {
     setName(tr("Vector Layer"));
 }
@@ -70,7 +70,6 @@ void LayerVector::loadImageAtFrame(QString path, int frameNumber)
     }
     VectorImage* vecImg = new VectorImage;
     vecImg->setPos(frameNumber);
-    vecImg->setObject(object());
     vecImg->read(path);
     addKeyFrame(frameNumber, vecImg);
 }
@@ -106,11 +105,10 @@ Status LayerVector::saveKeyFrameFile(KeyFrame* keyFrame, QString path)
     return Status::OK;
 }
 
-KeyFrame* LayerVector::createKeyFrame(int position, Object* obj)
+KeyFrame* LayerVector::createKeyFrame(int position)
 {
     VectorImage* v = new VectorImage;
     v->setPos(position);
-    v->setObject(obj);
     return v;
 }
 
diff --git a/core_lib/src/structure/layervector.h b/core_lib/src/structure/layervector.h
index 563a1800b..163cdc0a4 100644
--- a/core_lib/src/structure/layervector.h
+++ b/core_lib/src/structure/layervector.h
@@ -27,7 +27,7 @@ class LayerVector : public Layer
     Q_OBJECT
 
 public:
-    LayerVector(Object* object);
+    explicit LayerVector(int id);
     ~LayerVector();
 
     // method from layerImage
@@ -45,7 +45,7 @@ class LayerVector : public Layer
 
 protected:
     Status saveKeyFrameFile(KeyFrame*, QString path) override;
-    KeyFrame* createKeyFrame(int position, Object*) override;
+    KeyFrame* createKeyFrame(int position) override;
 
 private:
     QString fileName(KeyFrame* key) const;
diff --git a/core_lib/src/structure/object.cpp b/core_lib/src/structure/object.cpp
index 30391fed5..17834e6f7 100644
--- a/core_lib/src/structure/object.cpp
+++ b/core_lib/src/structure/object.cpp
@@ -97,16 +97,16 @@ bool Object::loadXML(const QDomElement& docElem, ProgressCallback progressForwar
         switch (element.attribute("type").toInt())
         {
         case Layer::BITMAP:
-            newLayer = new LayerBitmap(this);
+            newLayer = new LayerBitmap(getUniqueLayerID());
             break;
         case Layer::VECTOR:
-            newLayer = new LayerVector(this);
+            newLayer = new LayerVector(getUniqueLayerID());
             break;
         case Layer::SOUND:
-            newLayer = new LayerSound(this);
+            newLayer = new LayerSound(getUniqueLayerID());
             break;
         case Layer::CAMERA:
-            newLayer = new LayerCamera(this);
+            newLayer = new LayerCamera(getUniqueLayerID());
             break;
         default:
             Q_UNREACHABLE();
@@ -119,7 +119,7 @@ bool Object::loadXML(const QDomElement& docElem, ProgressCallback progressForwar
 
 LayerBitmap* Object::addNewBitmapLayer()
 {
-    LayerBitmap* layerBitmap = new LayerBitmap(this);
+    LayerBitmap* layerBitmap = new LayerBitmap(getUniqueLayerID());
     mLayers.append(layerBitmap);
 
     layerBitmap->addNewKeyFrameAt(1);
@@ -129,7 +129,7 @@ LayerBitmap* Object::addNewBitmapLayer()
 
 LayerVector* Object::addNewVectorLayer()
 {
-    LayerVector* layerVector = new LayerVector(this);
+    LayerVector* layerVector = new LayerVector(getUniqueLayerID());
     mLayers.append(layerVector);
 
     layerVector->addNewKeyFrameAt(1);
@@ -139,7 +139,7 @@ LayerVector* Object::addNewVectorLayer()
 
 LayerSound* Object::addNewSoundLayer()
 {
-    LayerSound* layerSound = new LayerSound(this);
+    LayerSound* layerSound = new LayerSound(getUniqueLayerID());
     mLayers.append(layerSound);
 
     // No default keyFrame at position 1 for Sound layer.
@@ -149,7 +149,7 @@ LayerSound* Object::addNewSoundLayer()
 
 LayerCamera* Object::addNewCameraLayer()
 {
-    LayerCamera* layerCamera = new LayerCamera(this);
+    LayerCamera* layerCamera = new LayerCamera(getUniqueLayerID());
     mLayers.append(layerCamera);
 
     layerCamera->addNewKeyFrameAt(1);
@@ -378,7 +378,7 @@ bool Object::addLayer(Layer* layer)
     {
         return false;
     }
-    layer->setObject(this);
+    layer->setId(getUniqueLayerID());
     mLayers.append(layer);
     return true;
 }
@@ -456,7 +456,7 @@ void Object::removeColor(int index)
 
     mPalette.removeAt(index);
 
-    // update the vector pictures using that color !
+    // update the vector pictures using that color!
 }
 
 void Object::renameColor(int i, const QString& text)
@@ -507,8 +507,8 @@ void Object::exportPalettePencil(QFile& file) const
         tag.setAttribute("alpha", ref.color.alpha());
         root.appendChild(tag);
     }
-    int IndentSize = 2;
-    doc.save(out, IndentSize);
+    int indentSize = 2;
+    doc.save(out, indentSize);
 }
 
 bool Object::exportPalette(const QString& filePath) const
@@ -542,7 +542,7 @@ void Object::importPaletteGPL(QFile& file)
     QTextStream in(&file);
     QString line;
 
-    // First line must start with "GIMP Palette"
+    // The first line must start with "GIMP Palette"
     // Displaying an error here would be nice
     in.readLineInto(&line);
     if (!line.startsWith("GIMP Palette")) return;
@@ -553,16 +553,16 @@ void Object::importPaletteGPL(QFile& file)
     if (line.startsWith("Name: "))
     {
         in.readLineInto(&line);
-        // The new format contains an optional thrid line starting with "Columns: "
+        // The new format contains an optional third line starting with "Columns: "
         if (line.startsWith("Columns: "))
         {
-            // Skip to next line
+            // Skip to the next line
             in.readLineInto(&line);
         }
     }
 
     // Colors inherit the value from the previous color for missing channels
-    // Some palettes may rely on this behavior so we should try to replicate it
+    // Some palettes may rely on this behavior, so we should try to replicate it
     QColor prevColor(Qt::black);
 
     do
@@ -606,7 +606,7 @@ void Object::importPaletteGPL(QFile& file)
         if (countInLine < 2) green = prevColor.green();
         if (countInLine < 3) blue = prevColor.blue();
 
-        // GIMP assigns colors the name "Untitled" by default now
+        // GIMP assigns colors the name "Untitled" by default now,
         // so in addition to missing names, we also use automatic
         // naming for this
         if (name.isEmpty() || name == "Untitled") name = QString();
@@ -755,7 +755,7 @@ void Object::paintImage(QPainter& painter,int frameNumber,
             if (vec)
             {
                 painter.setOpacity(vec->getOpacity());
-                vec->paintImage(painter, false, false, antialiasing);
+                vec->paintImage(painter, *this, false, false, antialiasing);
             }
         }
     }
@@ -815,7 +815,7 @@ bool Object::exportFrames(int frameStart, int frameEnd,
     {
         format = "JPG";
         extension = ".jpg";
-        transparency = false; // JPG doesn't support transparency so we have to include the background
+        transparency = false; // JPG doesn't support transparency, so we have to include the background
     }
     if (formatStr == "TIFF" || formatStr == "tiff" || formatStr == "TIF" || formatStr == "tif")
     {
diff --git a/core_lib/src/structure/object.h b/core_lib/src/structure/object.h
index 6ed45a318..c7701d06b 100644
--- a/core_lib/src/structure/object.h
+++ b/core_lib/src/structure/object.h
@@ -45,10 +45,10 @@ class Object final
     explicit Object();
     ~Object();
 
-	Object(Object const&) = delete;
-	Object(Object&&) = delete;
-	Object& operator=(Object const&) = delete;
-	Object& operator=(Object&&) = delete;
+    Object(Object const&) = delete;
+    Object(Object&&) = delete;
+    Object& operator=(Object const&) = delete;
+    Object& operator=(Object&&) = delete;
 
     void init();
     void createWorkingDir();
diff --git a/tests/src/test_layer.cpp b/tests/src/test_layer.cpp
index 39eb0be60..73478d105 100644
--- a/tests/src/test_layer.cpp
+++ b/tests/src/test_layer.cpp
@@ -26,43 +26,37 @@ GNU General Public License for more details.
 
 TEST_CASE("LayerType")
 {
-    Object* object = new Object;
-
     SECTION("Bitmap Layer")
     {
-        Layer* bitmapLayer = new LayerBitmap(object);
+        Layer* bitmapLayer = new LayerBitmap(1);
         REQUIRE(bitmapLayer->type() == Layer::BITMAP);
         delete bitmapLayer;
     }
     SECTION("Vector Layer")
     {
-        Layer* vecLayer = new LayerVector(object);
+        Layer* vecLayer = new LayerVector(2);
         REQUIRE(vecLayer->type() == Layer::VECTOR);
         delete vecLayer;
     }
     SECTION("Camera Layer")
     {
-        Layer* cameraLayer = new LayerCamera(object);
+        Layer* cameraLayer = new LayerCamera(3);
         REQUIRE(cameraLayer->type() == Layer::CAMERA);
         delete cameraLayer;
     }
     SECTION("Sound Layer")
     {
-        Layer* soundLayer = new LayerSound(object);
+        Layer* soundLayer = new LayerSound(4);
         REQUIRE(soundLayer->type() == Layer::SOUND);
         delete soundLayer;
     }
-
-    delete object;
 }
 
 SCENARIO("Add key frames into a Layer", "[Layer]")
 {
-    Object* object = new Object;
-
     GIVEN("A Bitmap Layer")
     {
-        Layer* layer = new LayerBitmap(object);
+        Layer* layer = new LayerBitmap(1);
 
         REQUIRE(layer->addNewKeyFrameAt(0) == false); // first key position is 1.
         REQUIRE(layer->keyFrameCount() == 0);
@@ -96,7 +90,7 @@ SCENARIO("Add key frames into a Layer", "[Layer]")
 
     GIVEN("A Vector Layer")
     {
-        Layer* layer = new LayerVector(object);
+        Layer* layer = new LayerVector(2);
 
         REQUIRE(layer->addNewKeyFrameAt(0) == false); // first key position is 1.
         REQUIRE(layer->keyFrameCount() == 0);
@@ -117,7 +111,7 @@ SCENARIO("Add key frames into a Layer", "[Layer]")
 
     GIVEN("A Camera Layer")
     {
-        Layer* layer = new LayerCamera(object);
+        Layer* layer = new LayerCamera(3);
 
         REQUIRE(layer->addNewKeyFrameAt(0) == false); // first key position is 1.
         REQUIRE(layer->keyFrameCount() == 0);
@@ -135,7 +129,6 @@ SCENARIO("Add key frames into a Layer", "[Layer]")
         }
         delete layer;
     }
-    delete object;
 }
 
 TEST_CASE("Test Layer::keyExists()", "[Layer]")
diff --git a/tests/src/test_layercamera.cpp b/tests/src/test_layercamera.cpp
index c37afdc26..f6899d73f 100644
--- a/tests/src/test_layercamera.cpp
+++ b/tests/src/test_layercamera.cpp
@@ -26,11 +26,9 @@ GNU General Public License for more details.
 
 SCENARIO("Create camera keyframe with linear easing")
 {
-    Object* object = new Object;
-
     GIVEN("A Camera Layer with one keyframe")
     {
-        Layer* layer = new LayerCamera(object);
+        Layer* layer = new LayerCamera(1);
         LayerCamera* camLayer = static_cast<LayerCamera*>(layer);
 
         WHEN("Adding a keyframe")
@@ -46,17 +44,13 @@ SCENARIO("Create camera keyframe with linear easing")
             }
         }
     }
-
-    delete object;
 }
 
 SCENARIO("Add a second keyframe and see that the path point of the first keyframe is updated")
 {
-    Object* object = new Object;
-
     GIVEN("A Camera layer with multiple keyframes")
     {
-        Layer* layer = new LayerCamera(object);
+        Layer* layer = new LayerCamera(1);
         LayerCamera* camLayer = static_cast<LayerCamera*>(layer);
 
         layer->addNewKeyFrameAt(1);
@@ -75,17 +69,13 @@ SCENARIO("Add a second keyframe and see that the path point of the first keyfram
             }
         }
     }
-
-    delete object;
 }
 
 SCENARIO("Add keyframe after having interpolated the previous keyframe and see that the translation is kept")
 {
-    Object* object = new Object;
-
     GIVEN("A Camera layer with multiple keyframes")
     {
-        Layer* layer = new LayerCamera(object);
+        Layer* layer = new LayerCamera(1);
         LayerCamera* camLayer = static_cast<LayerCamera*>(layer);
 
         layer->addNewKeyFrameAt(1);
@@ -102,17 +92,13 @@ SCENARIO("Add keyframe after having interpolated the previous keyframe and see t
             }
         }
     }
-
-    delete object;
 }
 
 SCENARIO("Remove a camera keyframe and see that the path is properly reset")
 {
-    Object* object = new Object;
-
     GIVEN("A Camera layer with multiple keyframes")
     {
-        Layer* layer = new LayerCamera(object);
+        Layer* layer = new LayerCamera(1);
         LayerCamera* camLayer = static_cast<LayerCamera*>(layer);
 
         layer->addNewKeyFrameAt(1);
@@ -132,17 +118,13 @@ SCENARIO("Remove a camera keyframe and see that the path is properly reset")
             }
         }
     }
-
-    delete object;
 }
 
 SCENARIO("When deleting an in between keyframe, the previous keyframe will try to recover its initial control point, if possible")
 {
-    Object* object = new Object;
-
     GIVEN("A Camera layer with multiple keyframes where the keys are added sequentially")
     {
-        Layer* layer = new LayerCamera(object);
+        Layer* layer = new LayerCamera(1);
         LayerCamera* camLayer = static_cast<LayerCamera*>(layer);
 
         layer->addNewKeyFrameAt(1);
@@ -169,7 +151,7 @@ SCENARIO("When deleting an in between keyframe, the previous keyframe will try t
 
     GIVEN("A Camera layer with multiple keyframes where the third frame is added in-between")
     {
-        Layer* layer = new LayerCamera(object);
+        Layer* layer = new LayerCamera(2);
         LayerCamera* camLayer = static_cast<LayerCamera*>(layer);
 
         layer->addNewKeyFrameAt(1);
@@ -196,17 +178,13 @@ SCENARIO("When deleting an in between keyframe, the previous keyframe will try t
             }
         }
     }
-
-    delete object;
 }
 
 SCENARIO("When adding a keyframe in-between two othes where the control points has been modified, the curve will be preserved")
 {
-    Object* object = new Object;
-
     GIVEN("A Camera layer with multiple keyframes where the third frame is added in-between")
     {
-        Layer* layer = new LayerCamera(object);
+        Layer* layer = new LayerCamera(1);
         LayerCamera* camLayer = static_cast<LayerCamera*>(layer);
 
         layer->addNewKeyFrameAt(1);
@@ -233,8 +211,6 @@ SCENARIO("When adding a keyframe in-between two othes where the control points h
             }
         }
     }
-
-    delete object;
 }
 
 SCENARIO("Loading a project and see that all camera properties are set, if applicable")