C++ LayerImage::addCel方法代码示例

void Document::copyLayerContent(const Layer* sourceLayer0, Document* destDoc, Layer* destLayer0) const
{
  // Copy the layer name
  destLayer0->setName(sourceLayer0->name());

  if (sourceLayer0->isImage() && destLayer0->isImage()) {
    const LayerImage* sourceLayer = static_cast<const LayerImage*>(sourceLayer0);
    LayerImage* destLayer = static_cast<LayerImage*>(destLayer0);

    // copy cels
    CelConstIterator it = sourceLayer->getCelBegin();
    CelConstIterator end = sourceLayer->getCelEnd();

    for (; it != end; ++it) {
      const Cel* sourceCel = *it;
      if (sourceCel->frame() > destLayer->sprite()->lastFrame())
        break;

      base::UniquePtr<Cel> newCel(new Cel(*sourceCel));

      const Image* sourceImage = sourceCel->image();
      ASSERT(sourceImage != NULL);

      Image* newImage = Image::createCopy(sourceImage);
      newCel->setImage(destLayer->sprite()->stock()->addImage(newImage));

      destLayer->addCel(newCel);
      newCel.release();
    }
  }
  else if (sourceLayer0->isFolder() && destLayer0->isFolder()) {
    const LayerFolder* sourceLayer = static_cast<const LayerFolder*>(sourceLayer0);
    LayerFolder* destLayer = static_cast<LayerFolder*>(destLayer0);

    LayerConstIterator it = sourceLayer->getLayerBegin();
    LayerConstIterator end = sourceLayer->getLayerEnd();

    for (; it != end; ++it) {
      Layer* sourceChild = *it;
      base::UniquePtr<Layer> destChild(NULL);

      if (sourceChild->isImage()) {
        destChild.reset(new LayerImage(destLayer->sprite()));
        copyLayerContent(sourceChild, destDoc, destChild);
      }
      else if (sourceChild->isFolder()) {
        destChild.reset(new LayerFolder(destLayer->sprite()));
        copyLayerContent(sourceChild, destDoc, destChild);
      }
      else {
        ASSERT(false);
      }

      ASSERT(destChild != NULL);

      // Add the new layer in the sprite.

      Layer* newLayer = destChild.release();
      Layer* afterThis = destLayer->getLastLayer();

      destLayer->addLayer(newLayer);
      destChild.release();

      destLayer->stackLayer(newLayer, afterThis);
    }
  }
  else  {
    ASSERT(false && "Trying to copy two incompatible layers");
  }
}

bool FliFormat::onLoad(FileOp* fop)
{
#define SETPAL()                                                \
  do {                                                          \
      for (c=0; c<256; c++) {                                   \
        pal->setEntry(c, _rgba(cmap[c*3],                       \
                               cmap[c*3+1],                     \
                               cmap[c*3+2], 255));              \
      }                                                         \
      pal->setFrame(frpos_out);                                 \
      sprite->setPalette(pal, true);                            \
    } while (0)

  unsigned char cmap[768];
  unsigned char omap[768];
  s_fli_header fli_header;
  Image *bmp, *old, *image;
  Sprite *sprite;
  LayerImage *layer;
  Palette *pal;
  int c, w, h;
  FrameNumber frpos_in;
  FrameNumber frpos_out;
  int index = 0;
  Cel *cel;

  /* open the file to read in binary mode */
  FileHandle f(fop->filename.c_str(), "rb");

  fli_read_header(f, &fli_header);
  fseek(f, 128, SEEK_SET);

  if (fli_header.magic == NO_HEADER) {
    fop_error(fop, "The file doesn't have a FLIC header\n");
    return false;
  }

  /* size by frame */
  w = fli_header.width;
  h = fli_header.height;

  /* create the bitmaps */
  bmp = Image::create(IMAGE_INDEXED, w, h);
  old = Image::create(IMAGE_INDEXED, w, h);
  pal = new Palette(FrameNumber(0), 256);
  if (!bmp || !old || !pal) {
    fop_error(fop, "Not enough memory.\n");
    if (bmp) image_free(bmp);
    if (old) image_free(old);
    if (pal) delete pal;
    return false;
  }

  // Create the image
  sprite = new Sprite(IMAGE_INDEXED, w, h, 256);
  layer = new LayerImage(sprite);
  sprite->getFolder()->addLayer(layer);
  layer->configureAsBackground();

  // Set frames and speed
  sprite->setTotalFrames(FrameNumber(fli_header.frames));
  sprite->setDurationForAllFrames(fli_header.speed);

  /* write frame by frame */
  for (frpos_in = frpos_out = FrameNumber(0);
       frpos_in < sprite->getTotalFrames();
       ++frpos_in) {
    /* read the frame */
    fli_read_frame(f, &fli_header,
                   (unsigned char *)old->dat, omap,
                   (unsigned char *)bmp->dat, cmap);

    /* first frame, or the frames changes, or the palette changes */
    if ((frpos_in == 0) ||
        (image_count_diff(old, bmp))
#ifndef USE_LINK /* TODO this should be configurable through a check-box */
        || (memcmp(omap, cmap, 768) != 0)
#endif
        ) {
      /* the image changes? */
      if (frpos_in != 0)
        ++frpos_out;

      /* add the new frame */
      image = Image::createCopy(bmp);
      if (!image) {
        fop_error(fop, "Not enough memory\n");
        break;
      }

      index = sprite->getStock()->addImage(image);
      if (index < 0) {
        image_free(image);
        fop_error(fop, "Not enough memory\n");
        break;
      }

      cel = new Cel(frpos_out, index);
      layer->addCel(cel);

//.........这里部分代码省略.........

void FlattenLayers::onExecute()
{
  Sprite* sprite = this->sprite();
  auto doc = static_cast<Doc*>(sprite->document());

  // Create a temporary image.
  ImageRef image(Image::create(sprite->pixelFormat(),
      sprite->width(),
      sprite->height()));

  LayerImage* flatLayer;  // The layer onto which everything will be flattened.
  color_t     bgcolor;    // The background color to use for flatLayer.

  flatLayer = sprite->backgroundLayer();
  if (flatLayer && flatLayer->isVisible()) {
    // There exists a visible background layer, so we will flatten onto that.
    bgcolor = doc->bgColor(flatLayer);
  }
  else {
    // Create a new transparent layer to flatten everything onto.
    flatLayer = new LayerImage(sprite);
    ASSERT(flatLayer->isVisible());
    executeAndAdd(new cmd::AddLayer(sprite->root(), flatLayer, nullptr));
    executeAndAdd(new cmd::SetLayerName(flatLayer, "Flattened"));
    bgcolor = sprite->transparentColor();
  }

  render::Render render;
  render.setBgType(render::BgType::NONE);

  // Copy all frames to the background.
  for (frame_t frame(0); frame<sprite->totalFrames(); ++frame) {
    // Clear the image and render this frame.
    clear_image(image.get(), bgcolor);
    render.renderSprite(image.get(), sprite, frame);

    // TODO Keep cel links when possible

    ImageRef cel_image;
    Cel* cel = flatLayer->cel(frame);
    if (cel) {
      if (cel->links())
        executeAndAdd(new cmd::UnlinkCel(cel));

      cel_image = cel->imageRef();
      ASSERT(cel_image);

      executeAndAdd(new cmd::CopyRect(cel_image.get(), image.get(),
          gfx::Clip(0, 0, image->bounds())));
    }
    else {
      cel_image.reset(Image::createCopy(image.get()));
      cel = new Cel(frame, cel_image);
      flatLayer->addCel(cel);
    }
  }

  // Delete old layers.
  LayerList layers = sprite->root()->layers();
  for (Layer* layer : layers)
    if (layer != flatLayer)
      executeAndAdd(new cmd::RemoveLayer(layer));
}

void Document::copyLayerContent(const Layer* sourceLayer0, Document* destDoc, Layer* destLayer0) const
{
  LayerFlags dstFlags = sourceLayer0->flags();

  // Remove the "background" flag if the destDoc already has a background layer.
  if (((int)dstFlags & (int)LayerFlags::Background) == (int)LayerFlags::Background &&
      (destDoc->sprite()->backgroundLayer())) {
    dstFlags = (LayerFlags)((int)dstFlags & ~(int)(LayerFlags::BackgroundLayerFlags));
  }

  // Copy the layer name
  destLayer0->setName(sourceLayer0->name());
  destLayer0->setFlags(dstFlags);

  if (sourceLayer0->isImage() && destLayer0->isImage()) {
    const LayerImage* sourceLayer = static_cast<const LayerImage*>(sourceLayer0);
    LayerImage* destLayer = static_cast<LayerImage*>(destLayer0);

    // copy cels
    CelConstIterator it = sourceLayer->getCelBegin();
    CelConstIterator end = sourceLayer->getCelEnd();

    std::map<ObjectId, Cel*> linked;

    for (; it != end; ++it) {
      const Cel* sourceCel = *it;
      if (sourceCel->frame() > destLayer->sprite()->lastFrame())
        break;

      base::UniquePtr<Cel> newCel;

      auto it = linked.find(sourceCel->data()->id());
      if (it != linked.end()) {
        newCel.reset(Cel::createLink(it->second));
        newCel->setFrame(sourceCel->frame());
      }
      else {
        newCel.reset(Cel::createCopy(sourceCel));
        linked.insert(std::make_pair(sourceCel->data()->id(), newCel.get()));
      }

      destLayer->addCel(newCel);
      newCel.release();
    }
  }
  else if (sourceLayer0->isFolder() && destLayer0->isFolder()) {
    const LayerFolder* sourceLayer = static_cast<const LayerFolder*>(sourceLayer0);
    LayerFolder* destLayer = static_cast<LayerFolder*>(destLayer0);

    LayerConstIterator it = sourceLayer->getLayerBegin();
    LayerConstIterator end = sourceLayer->getLayerEnd();

    for (; it != end; ++it) {
      Layer* sourceChild = *it;
      base::UniquePtr<Layer> destChild(NULL);

      if (sourceChild->isImage()) {
        destChild.reset(new LayerImage(destLayer->sprite()));
        copyLayerContent(sourceChild, destDoc, destChild);
      }
      else if (sourceChild->isFolder()) {
        destChild.reset(new LayerFolder(destLayer->sprite()));
        copyLayerContent(sourceChild, destDoc, destChild);
      }
      else {
        ASSERT(false);
      }

      ASSERT(destChild != NULL);

      // Add the new layer in the sprite.

      Layer* newLayer = destChild.release();
      Layer* afterThis = destLayer->getLastLayer();

      destLayer->addLayer(newLayer);
      destChild.release();

      destLayer->stackLayer(newLayer, afterThis);
    }
  }
  else  {
    ASSERT(false && "Trying to copy two incompatible layers");
  }
}

bool FliFormat::onLoad(FileOp* fop)
{
  // Open the file to read in binary mode
  FileHandle handle(open_file_with_exception(fop->filename, "rb"));
  FILE* f = handle.get();
  flic::StdioFileInterface finterface(f);
  flic::Decoder decoder(&finterface);

  flic::Header header;
  if (!decoder.readHeader(header)) {
    fop_error(fop, "The file doesn't have a FLIC header\n");
    return false;
  }

  // Size by frame
  int w = header.width;
  int h = header.height;

  // Create a temporal bitmap
  ImageRef bmp(Image::create(IMAGE_INDEXED, w, h));
  Palette pal(0, 1);
  Cel* prevCel = nullptr;

  // Create the sprite
  Sprite* sprite = new Sprite(IMAGE_INDEXED, w, h, 256);
  LayerImage* layer = new LayerImage(sprite);
  sprite->folder()->addLayer(layer);
  layer->configureAsBackground();

  // Set frames and speed
  sprite->setTotalFrames(frame_t(header.frames));
  sprite->setDurationForAllFrames(header.speed);

  flic::Frame fliFrame;
  flic::Colormap oldFliColormap;
  fliFrame.pixels = bmp->getPixelAddress(0, 0);
  fliFrame.rowstride = IndexedTraits::getRowStrideBytes(bmp->width());

  frame_t frame_out = 0;
  for (frame_t frame_in=0;
       frame_in<sprite->totalFrames();
       ++frame_in) {
    // Read the frame
    if (!decoder.readFrame(fliFrame)) {
      fop_error(fop, "Error reading frame %d\n", frame_in);
      continue;
    }

    // Palette change
    bool palChange = false;
    if (frame_out == 0 || oldFliColormap != fliFrame.colormap) {
      oldFliColormap = fliFrame.colormap;

      pal.resize(fliFrame.colormap.size());
      for (int c=0; c<int(fliFrame.colormap.size()); c++) {
        pal.setEntry(c, rgba(fliFrame.colormap[c].r,
                             fliFrame.colormap[c].g,
                             fliFrame.colormap[c].b, 255));
      }
      pal.setFrame(frame_out);
      sprite->setPalette(&pal, true);

      palChange = true;
    }

    // First frame, or the frame changes
    if (!prevCel ||
        (count_diff_between_images(prevCel->image(), bmp.get()))) {
      // Add the new frame
      ImageRef image(Image::createCopy(bmp.get()));
      Cel* cel = new Cel(frame_out, image);
      layer->addCel(cel);

      prevCel = cel;
      ++frame_out;
    }
    else if (palChange) {
      Cel* cel = Cel::createLink(prevCel);
      cel->setFrame(frame_out);
      layer->addCel(cel);

      ++frame_out;
    }
    // The palette and the image don't change: add duration to the last added frame
    else {
      sprite->setFrameDuration(
        frame_out-1, sprite->frameDuration(frame_out-1) + header.speed);
    }

    if (header.frames > 0)
      fop_progress(fop, (float)(frame_in+1) / (float)(header.frames));

    if (fop_is_stop(fop))
      break;

    if (fop->oneframe)
      break;
  }

  if (frame_out > 0)
//.........这里部分代码省略.........

bool FliFormat::onLoad(FileOp* fop)
{
#define SETPAL()                                                \
  do {                                                          \
      for (c=0; c<256; c++) {                                   \
        pal->setEntry(c, rgba(cmap[c*3],                       \
                               cmap[c*3+1],                     \
                               cmap[c*3+2], 255));              \
      }                                                         \
      pal->setFrame(frpos_out);                                 \
      sprite->setPalette(pal, true);                            \
    } while (0)

  unsigned char cmap[768];
  unsigned char omap[768];
  s_fli_header fli_header;
  int c, w, h;
  frame_t frpos_in;
  frame_t frpos_out;
#ifdef USE_LINK
  int index = 0;                // TODO this is used to create linked cels
#endif

  // Open the file to read in binary mode
  FileHandle handle(open_file_with_exception(fop->filename, "rb"));
  FILE* f = handle.get();

  fli_read_header(f, &fli_header);
  fseek(f, 128, SEEK_SET);

  if (fli_header.magic == NO_HEADER) {
    fop_error(fop, "The file doesn't have a FLIC header\n");
    return false;
  }

  // Size by frame
  w = fli_header.width;
  h = fli_header.height;

  // Create the bitmaps
  base::UniquePtr<Image> bmp(Image::create(IMAGE_INDEXED, w, h));
  base::UniquePtr<Image> old(Image::create(IMAGE_INDEXED, w, h));
  base::UniquePtr<Palette> pal(new Palette(frame_t(0), 256));

  // Create the image
  Sprite* sprite = new Sprite(IMAGE_INDEXED, w, h, 256);
  LayerImage* layer = new LayerImage(sprite);
  sprite->folder()->addLayer(layer);
  layer->configureAsBackground();

  // Set frames and speed
  sprite->setTotalFrames(frame_t(fli_header.frames));
  sprite->setDurationForAllFrames(fli_header.speed);

  // Write frame by frame
  for (frpos_in = frpos_out = frame_t(0);
       frpos_in < sprite->totalFrames();
       ++frpos_in) {
    // Read the frame
    fli_read_frame(f, &fli_header,
                   (unsigned char *)old->getPixelAddress(0, 0), omap,
                   (unsigned char *)bmp->getPixelAddress(0, 0), cmap);

    // First frame, or the frames changes, or the palette changes
    if ((frpos_in == 0) ||
        (count_diff_between_images(old, bmp))
#ifndef USE_LINK /* TODO this should be configurable through a check-box */
        || (memcmp(omap, cmap, 768) != 0)
#endif
        ) {
      // The image changes?
      if (frpos_in != 0)
        ++frpos_out;

      // Add the new frame
      ImageRef image(Image::createCopy(bmp));
      Cel* cel = new Cel(frpos_out, image);
      layer->addCel(cel);

      // First frame or the palette changes
      if ((frpos_in == 0) || (memcmp(omap, cmap, 768) != 0))
        SETPAL();
    }
#ifdef USE_LINK
    // The palette changes
    else if (memcmp(omap, cmap, 768) != 0) {
      ++frpos_out;
      SETPAL();

      // Add link
      Cel* cel = new Cel(frpos_out, index);
      layer_add_cel(layer, cel);
    }
#endif
    // The palette and the image don't change: add duration to the last added frame
    else {
      sprite->setFrameDuration(frpos_out,
                               sprite->frameDuration(frpos_out)+fli_header.speed);
    }

//.........这里部分代码省略.........

void UndoTransaction::flattenLayers(int bgcolor)
{
  Image* cel_image;
  Cel* cel;
  int frame;

  // create a temporary image
  UniquePtr<Image> image_wrap(Image::create(m_sprite->getPixelFormat(),
                                            m_sprite->getWidth(),
                                            m_sprite->getHeight()));
  Image* image = image_wrap.get();

  /* get the background layer from the sprite */
  LayerImage* background = m_sprite->getBackgroundLayer();
  if (!background) {
    /* if there aren't a background layer we must to create the background */
    background = new LayerImage(m_sprite);

    if (isEnabled())
      m_undoHistory->pushUndoer(new undoers::AddLayer(m_undoHistory->getObjects(),
          m_sprite->getFolder(), background));

    m_sprite->getFolder()->add_layer(background);

    if (isEnabled())
      m_undoHistory->pushUndoer(new undoers::MoveLayer(m_undoHistory->getObjects(),
          background));

    background->configureAsBackground();
  }

  /* copy all frames to the background */
  for (frame=0; frame<m_sprite->getTotalFrames(); frame++) {
    /* clear the image and render this frame */
    image_clear(image, bgcolor);
    layer_render(m_sprite->getFolder(), image, 0, 0, frame);

    cel = background->getCel(frame);
    if (cel) {
      cel_image = m_sprite->getStock()->getImage(cel->getImage());
      ASSERT(cel_image != NULL);

      /* we have to save the current state of `cel_image' in the undo */
      if (isEnabled()) {
        Dirty* dirty = new Dirty(cel_image, image);
        dirty->saveImagePixels(cel_image);
        m_undoHistory->pushUndoer(new undoers::DirtyArea(
            m_undoHistory->getObjects(), cel_image, dirty));
        delete dirty;
      }
    }
    else {
      /* if there aren't a cel in this frame in the background, we
         have to create a copy of the image for the new cel */
      cel_image = Image::createCopy(image);
      /* TODO error handling: if (!cel_image) { ... } */

      /* here we create the new cel (with the new image `cel_image') */
      cel = new Cel(frame, m_sprite->getStock()->addImage(cel_image));
      /* TODO error handling: if (!cel) { ... } */

      /* and finally we add the cel in the background */
      background->addCel(cel);
    }

    image_copy(cel_image, image, 0, 0);
  }

  /* select the background */
  if (m_sprite->getCurrentLayer() != background) {
    if (isEnabled())
      m_undoHistory->pushUndoer(new undoers::SetCurrentLayer(
          m_undoHistory->getObjects(), m_sprite));

    m_sprite->setCurrentLayer(background);
  }

  // Remove old layers.
  LayerList layers = m_sprite->getFolder()->get_layers_list();
  LayerIterator it = layers.begin();
  LayerIterator end = layers.end();

  for (; it != end; ++it) {
    if (*it != background) {
      Layer* old_layer = *it;

      // Remove the layer
      if (isEnabled())
        m_undoHistory->pushUndoer(new undoers::RemoveLayer(m_undoHistory->getObjects(),
            old_layer));

      m_sprite->getFolder()->remove_layer(old_layer);

      // Destroy the layer
      delete old_layer;
    }
  }
}

void Document::copyLayerContent(const Layer* sourceLayer0, Document* destDoc, Layer* destLayer0) const
{
  DocumentUndo* undo = destDoc->getUndo();

  // Copy the layer name
  destLayer0->setName(sourceLayer0->getName());

  if (sourceLayer0->isImage() && destLayer0->isImage()) {
    const LayerImage* sourceLayer = static_cast<const LayerImage*>(sourceLayer0);
    LayerImage* destLayer = static_cast<LayerImage*>(destLayer0);

    // copy cels
    CelConstIterator it = sourceLayer->getCelBegin();
    CelConstIterator end = sourceLayer->getCelEnd();

    for (; it != end; ++it) {
      const Cel* sourceCel = *it;
      UniquePtr<Cel> newCel(new Cel(*sourceCel));

      ASSERT((sourceCel->getImage() >= 0) &&
             (sourceCel->getImage() < sourceLayer->getSprite()->getStock()->size()));

      const Image* sourceImage = sourceLayer->getSprite()->getStock()->getImage(sourceCel->getImage());
      ASSERT(sourceImage != NULL);

      Image* newImage = Image::createCopy(sourceImage);
      newCel->setImage(destLayer->getSprite()->getStock()->addImage(newImage));

      if (undo->isEnabled()) {
        undo->pushUndoer(new undoers::AddImage(undo->getObjects(),
            destLayer->getSprite()->getStock(),
            newCel->getImage()));
      }

      destLayer->addCel(newCel);
      newCel.release();
    }
  }
  else if (sourceLayer0->isFolder() && destLayer0->isFolder()) {
    const LayerFolder* sourceLayer = static_cast<const LayerFolder*>(sourceLayer0);
    LayerFolder* destLayer = static_cast<LayerFolder*>(destLayer0);

    LayerConstIterator it = sourceLayer->getLayerBegin();
    LayerConstIterator end = sourceLayer->getLayerEnd();

    for (; it != end; ++it) {
      Layer* sourceChild = *it;
      UniquePtr<Layer> destChild(NULL);

      if (sourceChild->isImage()) {
        destChild.reset(new LayerImage(destLayer->getSprite()));
        copyLayerContent(sourceChild, destDoc, destChild);
      }
      else if (sourceChild->isFolder()) {
        destChild.reset(new LayerFolder(destLayer->getSprite()));
        copyLayerContent(sourceChild, destDoc, destChild);
      }
      else {
        ASSERT(false);
      }

      ASSERT(destChild != NULL);

      // Add the new layer in the sprite.
      destDoc->getApi().addLayer(destLayer,
                                 destChild.release(),
                                 destLayer->getLastLayer());
    }
  }
  else  {
    ASSERT(false && "Trying to copy two incompatible layers");
  }
}

void DocumentApi::flattenLayers(Sprite* sprite, int bgcolor)
{
  Image* cel_image;
  Cel* cel;

  DocumentUndo* undo = m_document->getUndo();

  // Create a temporary image.
  UniquePtr<Image> image_wrap(Image::create(sprite->getPixelFormat(),
                                            sprite->getWidth(),
                                            sprite->getHeight()));
  Image* image = image_wrap.get();

  // Get the background layer from the sprite.
  LayerImage* background = sprite->getBackgroundLayer();
  if (!background) {
    // If there aren't a background layer we must to create the background.
    background = new LayerImage(sprite);

    addLayer(sprite->getFolder(), background, NULL);
    configureLayerAsBackground(background);
  }

  // Copy all frames to the background.
  for (FrameNumber frame(0); frame<sprite->getTotalFrames(); ++frame) {
    // Clear the image and render this frame.
    image_clear(image, bgcolor);
    layer_render(sprite->getFolder(), image, 0, 0, frame);

    cel = background->getCel(frame);
    if (cel) {
      cel_image = sprite->getStock()->getImage(cel->getImage());
      ASSERT(cel_image != NULL);

      // We have to save the current state of `cel_image' in the undo.
      if (undo->isEnabled()) {
        Dirty* dirty = new Dirty(cel_image, image);
        dirty->saveImagePixels(cel_image);
        m_undoers->pushUndoer(new undoers::DirtyArea(
            getObjects(), cel_image, dirty));
        delete dirty;
      }
    }
    else {
      // If there aren't a cel in this frame in the background, we
      // have to create a copy of the image for the new cel.
      cel_image = Image::createCopy(image);
      // TODO error handling: if createCopy throws

      // Here we create the new cel (with the new image `cel_image').
      cel = new Cel(frame, sprite->getStock()->addImage(cel_image));
      // TODO error handling: if new Cel throws

      // And finally we add the cel in the background.
      background->addCel(cel);
    }

    image_copy(cel_image, image, 0, 0);
  }

  // Delete old layers.
  LayerList layers = sprite->getFolder()->getLayersList();
  LayerIterator it = layers.begin();
  LayerIterator end = layers.end();
  for (; it != end; ++it)
    if (*it != background)
      removeLayer(*it);
}