Method onUndo

src/app/cmd/add_cel.cpp:46–62

}

void AddCel::onUndo()
{
  Layer* layer = this->layer();
  auto cel = this->cel();

  // Save the CelData only if the cel isn't linked
  bool has_data = (cel->links() == 0);
  write8(m_stream, has_data ? 1: 0);
  if (has_data) {
    write_image(m_stream, cel->image());
    write_celdata(m_stream, cel->data());
  }
  write_cel(m_stream, cel.get());
  m_size = size_t(m_stream.tellp());

  removeCel(layer, cel);
}

void AddCel::onRedo()
{