Figure.cc

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////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2011-2021 The Octave Project Developers
//
// See the file COPYRIGHT.md in the top-level directory of this
// distribution or <https://octave.org/copyright/>.
//
// This file is part of Octave.
//
// Octave 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 3 of the License, or
// (at your option) any later version.
//
// Octave 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 Octave; see the file COPYING.  If not, see
// <https://www.gnu.org/licenses/>.
//
////////////////////////////////////////////////////////////////////////
 
#if defined (HAVE_CONFIG_H)
#  include "config.h"
#endif
 
#include <QAction>
#include <QActionEvent>
#include <QApplication>
#include <QClipboard>
#include <QEvent>
#include <QFileDialog>
#include <QFileInfo>
#include <QFrame>
#include <QImage>
#include <QMainWindow>
#include <QMenu>
#include <QMenuBar>
#include <QMessageBox>
#include <QtDebug>
#include <QTimer>
#include <QToolBar>
#if defined (HAVE_QSCREEN_DEVICEPIXELRATIO)
#  include <QWindow>
#  include <QScreen>
#endif
 
#include "Canvas.h"
#include "Container.h"
#include "Figure.h"
#include "FigureWindow.h"
#include "QtHandlesUtils.h"
 
#include "gui-preferences-global.h"
#include "qt-interpreter-events.h"
 
#include "file-ops.h"
#include "unwind-prot.h"
#include "utils.h"
#include "version.h"
 
#include "builtin-defun-decls.h"
#include "interpreter.h"
 
namespace QtHandles
{
 
  DECLARE_GENERICEVENTNOTIFY_SENDER(MenuBar, QMenuBar);
 
  static QRect
  boundingBoxToRect (const Matrix& bb)
  {
    QRect r;
 
    if (bb.numel () == 4)
      {
        r = QRect (octave::math::round (bb(0)), octave::math::round (bb(1)),
                   octave::math::round (bb(2)), octave::math::round (bb(3)));
        if (! r.isValid ())
          r = QRect ();
      }
 
    return r;
  }
 
  static QImage
  pointer_to_qimage (const Matrix& cdata)
  {
    QImage retval (cdata.rows (), cdata.columns (), QImage::Format_ARGB32);
    QColor tmp ("White");
    QColor black ("Black");
    QColor white ("White");
    for (octave_idx_type ii = 0; ii < cdata.rows (); ii++)
      for (octave_idx_type jj = 0; jj < cdata.columns (); jj++)
        {
          if (cdata(ii,jj) == 1.0)
            tmp = black;
          else if (cdata(ii,jj) == 2.0)
            tmp = white;
          else
            tmp.setAlpha (0);
 
          retval.setPixel (jj, ii, tmp.rgba ());
        }
 
    return retval;
  }
 
  Figure*
  Figure::create (octave::base_qobject& oct_qobj, octave::interpreter& interp,
                  const graphics_object& go)
  {
    return new Figure (oct_qobj, interp, go, new FigureWindow ());
  }
 
  Figure::Figure (octave::base_qobject& oct_qobj, octave::interpreter& interp,
                  const graphics_object& go, FigureWindow *win)
    : Object (oct_qobj, interp, go, win), m_blockUpdates (false),
      m_figureToolBar (nullptr), m_menuBar (nullptr), m_innerRect (),
      m_outerRect (), m_previousHeight (0), m_resizable (true)
  {
    m_container = new Container (win, oct_qobj, interp);
    win->setCentralWidget (m_container);
 
    connect (m_container, SIGNAL (interpeter_event (const fcn_callback&)),
             this, SIGNAL (interpeter_event (const fcn_callback&)));
 
    connect (m_container, SIGNAL (interpeter_event (const meth_callback&)),
             this, SIGNAL (interpeter_event (const meth_callback&)));
 
    figure::properties& fp = properties<figure> ();
 
    // Adjust figure position
    m_innerRect = boundingBoxToRect (fp.get_boundingbox (true));
    m_outerRect = boundingBoxToRect (fp.get_boundingbox (false));
 
    set_geometry (m_innerRect);
 
    // Menubar
    m_menuBar = new MenuBar (win);
    win->setMenuBar (m_menuBar);
    m_menuBar->addReceiver (this);
    m_menuBar->setStyleSheet (m_menuBar->styleSheet () + global_menubar_style);
 
 
    // Status bar
    m_statusBar = win->statusBar ();
    m_statusBar->setVisible (false);
 
    if (fp.toolbar_is ("figure")
        || (fp.toolbar_is ("auto") && fp.menubar_is ("figure")))
      showFigureStatusBar (true);
 
    // Enable mouse tracking unconditionally
    enableMouseTracking ();
 
    // When this constructor gets called all properties are already
    // set, even non default.  We force "update" here to get things right.
 
    // Figure title
    update (figure::properties::ID_NUMBERTITLE);
 
    // Decide what keyboard events we listen to
    m_container->canvas (m_handle)->setEventMask (0);
    update (figure::properties::ID_KEYPRESSFCN);
    update (figure::properties::ID_KEYRELEASEFCN);
 
    // modal style
    update (figure::properties::ID_WINDOWSTYLE);
 
    // Handle resizing constraints
    update (figure::properties::ID_RESIZE);
 
    // Custom pointer data
    update (figure::properties::ID_POINTERSHAPECDATA);
 
    // Visibility
    update (figure::properties::ID_VISIBLE);
 
    connect (this, SIGNAL (asyncUpdate (void)),
             this, SLOT (updateContainer (void)));
 
    // Register for the signal that indicates when a window has moved
    // to a different screen
    connect (win, SIGNAL (figureWindowShown ()),
             this, SLOT (figureWindowShown ()));
 
    win->addReceiver (this);
    m_container->addReceiver (this);
  }
 
  Figure::~Figure (void)
  { }
 
  QString
  Figure::fileName (void)
  {
    gh_manager& gh_mgr = m_interpreter.get_gh_manager ();
 
    octave::autolock guard (gh_mgr.graphics_lock ());
 
    const figure::properties& fp = properties<figure> ();
 
    std::string name = fp.get_filename ();
 
    return QString::fromStdString (name);
  }
 
  void
  Figure::setFileName (const QString& name)
  {
    gh_manager& gh_mgr = m_interpreter.get_gh_manager ();
 
    octave::autolock guard (gh_mgr.graphics_lock ());
 
    figure::properties& fp = properties<figure> ();
 
    fp.set_filename (name.toStdString ());
  }
 
  MouseMode
  Figure::mouseMode (void)
  {
    gh_manager& gh_mgr = m_interpreter.get_gh_manager ();
 
    octave::autolock guard (gh_mgr.graphics_lock ());
 
    const figure::properties& fp = properties<figure> ();
 
    std::string mode = fp.get___mouse_mode__ ();
 
    if (mode == "zoom")
      {
        octave_scalar_map zm = fp.get___zoom_mode__ ().scalar_map_value ();
 
        std::string direction = zm.getfield ("Direction").string_value ();
 
        mode += ' ' + direction;
      }
 
    if (mode == "rotate")
      return RotateMode;
    else if (mode == "zoom in")
      return ZoomInMode;
    else if (mode == "zoom out")
      return ZoomOutMode;
    else if (mode == "pan")
      return PanMode;
    else if (mode == "text")
      return TextMode;
 
    return NoMode;
  }
 
  void
  Figure::set_geometry (QRect r)
  {
    QMainWindow *win = qWidget<QMainWindow> ();
 
    if (! m_resizable)
      {
        win->setSizePolicy (QSizePolicy::Preferred, QSizePolicy::Preferred);
        win->setFixedSize (QSize( QWIDGETSIZE_MAX, QWIDGETSIZE_MAX));
      }
 
    // Unlock window if it is maximized or full-screen
    int state = win->windowState ();
    if (state == Qt::WindowFullScreen || state == Qt::WindowMaximized)
      win->setWindowState (Qt::WindowNoState);
 
    win->setGeometry (r);
 
    if (! m_resizable)
      {
        win->setSizePolicy (QSizePolicy::Fixed, QSizePolicy::Fixed);
        win->setFixedSize(win->size ());
      }
  }
 
  Container*
  Figure::innerContainer (void)
  {
    return m_container;
  }
 
  void
  Figure::redraw (void)
  {
    Canvas *canvas = m_container->canvas (m_handle);
 
    if (canvas)
      canvas->redraw ();
 
    for (auto *qobj : qWidget<QWidget> ()->findChildren<QObject*> ())
      {
        if (qobj->objectName () == "UIPanel"
            || qobj->objectName () == "UIButtonGroup"
            || qobj->objectName () == "UIControl"
            || qobj->objectName () == "UITable")
          {
            Object *obj = Object::fromQObject (qobj);
 
            if (obj)
              obj->slotRedraw ();
          }
      }
  }
 
  void
  Figure::show (void)
  {
    QWidget *win = qWidget<QWidget> ();
 
    win->activateWindow ();
    win->raise ();
  }
 
  void
  Figure::print (const QString& file_cmd, const QString& term)
  {
    Canvas *canvas = m_container->canvas (m_handle);
 
    if (canvas)
      canvas->print (file_cmd, term);
  }
 
  uint8NDArray
  Figure::slotGetPixels (void)
  {
    uint8NDArray retval;
    Canvas *canvas = m_container->canvas (m_handle);
 
    if (canvas)
      {
        gh_manager& gh_mgr = m_interpreter.get_gh_manager ();
 
        gh_mgr.process_events ();
        octave::autolock guard (gh_mgr.graphics_lock ());
        retval = canvas->getPixels ();
      }
 
    return retval;
  }
 
  void
  Figure::beingDeleted (void)
  {
    Canvas *canvas = m_container->canvas (m_handle.value (), false);
 
    if (canvas)
      canvas->blockRedraw (true);
 
    m_container->removeReceiver (this);
    qWidget<FigureWindow> ()->removeReceiver (this);
  }
 
  void
  Figure::update (int pId)
  {
    if (m_blockUpdates)
      return;
 
    figure::properties& fp = properties<figure> ();
 
    if (fp.is___printing__ ())
      return;
 
    QMainWindow *win = qWidget<QMainWindow> ();
 
    // If the window doesn't exist, there's nothing we can do.
    if (! win)
      return;
 
    m_blockUpdates = true;
 
    switch (pId)
      {
      case figure::properties::ID_POSITION:
        {
          m_innerRect = boundingBoxToRect (fp.get_boundingbox (true));
          int toffset = 0;
          int boffset = 0;
 
          for (auto *tb : win->findChildren<QToolBar*> ())
            if (! tb->isHidden ())
              toffset += tb->sizeHint ().height ();
 
          if (! m_menuBar->isHidden ())
            toffset += m_menuBar->sizeHint ().height ();
 
          if (! m_statusBar->isHidden ())
            boffset += m_statusBar->sizeHint ().height ();
 
          set_geometry (m_innerRect.adjusted (0, -toffset, 0, boffset));
        }
        break;
 
      case figure::properties::ID_NAME:
      case figure::properties::ID_NUMBERTITLE:
        win->setWindowTitle (Utils::fromStdString (fp.get_title ()));
        break;
 
      case figure::properties::ID_VISIBLE:
        if (fp.is_visible ())
          {
            QTimer::singleShot (0, win, SLOT (show ()));
            if (! fp.is___gl_window__ ())
              {
                gh_manager& gh_mgr = m_interpreter.get_gh_manager ();
 
                octave::autolock guard (gh_mgr.graphics_lock ());
                fp.set ("__gl_window__", "on");
              }
          }
        else
          win->hide ();
        break;
 
      case figure::properties::ID_RESIZE:
        if (fp.is_resize ())
          {
            win->setSizePolicy (QSizePolicy::Preferred, QSizePolicy::Preferred);
            win->setFixedSize (QSize( QWIDGETSIZE_MAX, QWIDGETSIZE_MAX));
            m_resizable = true;
          }
        else
          {
            win->setSizePolicy (QSizePolicy::Fixed, QSizePolicy::Fixed);
            win->setFixedSize(win->size ());
            m_resizable = false;
          }
        break;
 
      case figure::properties::ID_MENUBAR:
      case figure::properties::ID_TOOLBAR:
        if (fp.toolbar_is ("none"))
          showFigureStatusBar (false);
        else if (fp.toolbar_is ("figure"))
          showFigureStatusBar (true);
        else  // "auto"
          showFigureStatusBar (fp.menubar_is ("figure"));
        break;
 
      case figure::properties::ID_KEYPRESSFCN:
        if (fp.get_keypressfcn ().isempty ())
          m_container->canvas (m_handle)->clearEventMask (Canvas::KeyPress);
        else
          m_container->canvas (m_handle)->addEventMask (Canvas::KeyPress);
        // Signal the change to uipanels as well
        for (auto *qobj : qWidget<QWidget> ()->findChildren<QObject*> ())
          {
            if (qobj->objectName () == "UIPanel")
              {
                Object *obj = Object::fromQObject (qobj);
 
                if (obj)
                  {
                    if (fp.get_keypressfcn ().isempty ())
                      obj->innerContainer ()->canvas (m_handle)->
                        clearEventMask (Canvas::KeyPress);
                    else
                      obj->innerContainer ()->canvas (m_handle)->
                        addEventMask (Canvas::KeyPress);
                  }
              }
          }
        break;
 
      case figure::properties::ID_KEYRELEASEFCN:
        if (fp.get_keyreleasefcn ().isempty ())
          m_container->canvas (m_handle)->clearEventMask (Canvas::KeyRelease);
        else
          m_container->canvas (m_handle)->addEventMask (Canvas::KeyRelease);
        break;
        // Signal the change to uipanels as well
        for (auto *qobj : qWidget<QWidget> ()->findChildren<QObject*> ())
          {
            if (qobj->objectName () == "UIPanel")
              {
                Object *obj = Object::fromQObject (qobj);
 
                if (obj)
                  {
                    if (fp.get_keypressfcn ().isempty ())
                      obj->innerContainer ()->canvas (m_handle)->
                        clearEventMask (Canvas::KeyRelease);
                    else
                      obj->innerContainer ()->canvas (m_handle)->
                        addEventMask (Canvas::KeyRelease);
                  }
              }
          }
        break;
 
      case figure::properties::ID_WINDOWSTYLE:
        if (fp.windowstyle_is ("modal"))
          {
            bool is_visible = win->isVisible ();
 
            // if window is already visible, need to hide and reshow it in order to
            // make it use the modal settings
            if (is_visible)
              win->setVisible (false);
 
            win->setWindowModality (Qt::ApplicationModal);
            win->setVisible (is_visible);
          }
        else
          win->setWindowModality (Qt::NonModal);
 
        break;
 
      case figure::properties::ID_POINTERSHAPECDATA:
        m_pointer_cdata =
          pointer_to_qimage (fp.get_pointershapecdata ().matrix_value ());
        if (fp.get_pointer () != "custom")
          break;
        OCTAVE_FALLTHROUGH;
 
      case figure::properties::ID_POINTER:
      case figure::properties::ID_POINTERSHAPEHOTSPOT:
      case figure::properties::ID___MOUSE_MODE__:
      case figure::properties::ID___ZOOM_MODE__:
        m_container->canvas (m_handle)->setCursor (mouseMode (),
                                                   fp.get_pointer (),
                                                   m_pointer_cdata,
                                                   fp.get_pointershapehotspot ()
                                                   .matrix_value());
        break;
 
      default:
        break;
      }
 
    m_blockUpdates = false;
  }
 
  void
  Figure::showFigureStatusBar (bool visible)
  {
    if (m_statusBar
        && (! m_statusBar->isHidden ()) != visible)
      {
        int dy = m_statusBar->sizeHint ().height ();
        QRect r = qWidget<QWidget> ()->geometry ();
 
        if (! visible)
          r.adjust (0, 0, 0, -dy);
        else
          r.adjust (0, 0, 0, dy);
 
        m_blockUpdates = true;
        set_geometry (r);
        m_statusBar->setVisible (visible);
        m_blockUpdates = false;
 
        updateBoundingBox (false);
      }
  }
 
  void
  Figure::updateFigureHeight (int dh)
  {
    gh_manager& gh_mgr = m_interpreter.get_gh_manager ();
 
    octave::autolock guard (gh_mgr.graphics_lock ());
    graphics_object go = object ();
 
    if (go.valid_object () && dh != 0)
      {
        QRect r = qWidget<QWidget> ()->geometry ();
 
        r.adjust (0, dh, 0, 0);
 
        m_blockUpdates = true;
        set_geometry (r);
        m_blockUpdates = false;
 
        updateBoundingBox (false);
      }
  }
 
  void
  Figure::updateStatusBar (ColumnVector pt)
  {
    if (! m_statusBar->isHidden ())
      m_statusBar->showMessage (QString ("(%1, %2)")
                                .arg (pt(0), 0, 'g', 5)
                                .arg (pt(1), 0, 'g', 5));
  }
 
  void
  Figure::do_connections (const QObject *receiver, const QObject* /* emitter */)
  {
    Object::do_connections (receiver);
    Object::do_connections (receiver, m_container->canvas (m_handle));
  }
 
  QWidget*
  Figure::menu (void)
  {
    return qWidget<QMainWindow> ()->menuBar ();
  }
 
  void
  Figure::updateBoundingBox (bool internal, int flags)
  {
    QWidget *win = qWidget<QWidget> ();
    Matrix bb (1, 4);
    std::string prop;
 
    if (internal)
      {
        prop = "position";
        QRect r = m_innerRect;
 
        if (flags & UpdateBoundingBoxPosition)
          r.moveTopLeft (win->mapToGlobal (m_container->pos ()));
        if (flags & UpdateBoundingBoxSize)
          r.setSize (m_container->size ());
 
        if (r.isValid () && r != m_innerRect)
          {
            m_innerRect = r;
 
            bb(0) = r.x ();
            bb(1) = r.y ();
            bb(2) = r.width ();
            bb(3) = r.height ();
          }
        else
          return;
      }
    else
      {
        prop = "outerposition";
        QRect r = m_outerRect;
 
        if (flags & UpdateBoundingBoxPosition)
          r.moveTopLeft (win->pos ());
        if (flags & UpdateBoundingBoxSize)
          r.setSize (win->frameGeometry ().size ());
 
        if (r.isValid () && r != m_outerRect)
          {
            m_outerRect = r;
 
            bb(0) = r.x ();
            bb(1) = r.y ();
            bb(2) = r.width ();
            bb(3) = r.height ();
          }
        else
          return;
      }
 
    figure::properties& fp = properties<figure> ();
 
    emit gh_set_event (m_handle, prop, fp.bbox2position (bb), false,
                       prop == "position");
  }
 
  bool
  Figure::eventNotifyBefore (QObject *obj, QEvent *xevent)
  {
    if (! m_blockUpdates)
      {
        // Clicking the toolbar or the menubar makes this figure current
        if (xevent->type () == QEvent::MouseButtonPress)
          {
            figure::properties& fp = properties<figure> ();
 
            gh_manager& gh_mgr = m_interpreter.get_gh_manager ();
 
            graphics_object root = gh_mgr.get_object (0);
 
            if (fp.get_handlevisibility () == "on")
              root.set ("currentfigure",
                        fp.get___myhandle__ ().as_octave_value ());
          }
 
        if (obj == m_container)
          {
            // Do nothing...
          }
        else if (obj == m_menuBar)
          {
            switch (xevent->type ())
              {
              case QEvent::ActionAdded:
              case QEvent::ActionChanged:
              case QEvent::ActionRemoved:
                m_previousHeight = m_menuBar->sizeHint ().height ();
 
              default:
                break;
              }
          }
        else
          {
            switch (xevent->type ())
              {
              case QEvent::Close:
                xevent->ignore ();
                emit gh_callback_event (m_handle, "closerequestfcn");
                return true;
 
              default:
                break;
              }
          }
      }
 
    return false;
  }
 
  void
  Figure::eventNotifyAfter (QObject *watched, QEvent *xevent)
  {
    if (! m_blockUpdates)
      {
        if (watched == m_container)
          {
            gh_manager& gh_mgr = m_interpreter.get_gh_manager ();
 
            switch (xevent->type ())
              {
              case QEvent::Resize:
                updateBoundingBox (true, UpdateBoundingBoxSize);
                break;
 
              case QEvent::ChildAdded:
                if (dynamic_cast<QChildEvent *> (xevent)->child
                    ()->isWidgetType())
                  {
                    octave::autolock guard (gh_mgr.graphics_lock ());
                    update (figure::properties::ID_TOOLBAR);
 
                    enableMouseTracking ();
                  }
                break;
 
              case QEvent::ChildRemoved:
                if (dynamic_cast<QChildEvent *> (xevent)->child
                    ()->isWidgetType())
                  {
                    octave::autolock guard (gh_mgr.graphics_lock ());
                    update (figure::properties::ID_TOOLBAR);
                  }
                break;
 
              default:
                break;
              }
          }
        else if (watched == m_menuBar)
          {
            switch (xevent->type ())
              {
              case QEvent::ActionAdded:
              case QEvent::ActionChanged:
              case QEvent::ActionRemoved:
                // The menubar may have been resized if no action is visible
                {
                  QAction *a = dynamic_cast<QActionEvent *> (xevent)->action ();
                  int currentHeight = m_menuBar->sizeHint ().height ();
                  if (currentHeight != m_previousHeight
                      && ! a->isSeparator ())
                    updateFigureHeight (m_previousHeight - currentHeight);
                }
                break;
 
              default:
                break;
              }
          }
        else
          {
            switch (xevent->type ())
              {
              case QEvent::Move:
                updateBoundingBox (false, UpdateBoundingBoxPosition);
                updateBoundingBox (true, UpdateBoundingBoxPosition);
                break;
 
              case QEvent::Resize:
                updateBoundingBox (false, UpdateBoundingBoxSize);
                break;
 
              default:
                break;
              }
          }
      }
  }
 
  void
  Figure::addCustomToolBar (QToolBar *bar, bool visible, bool isdefault)
  {
    QMainWindow *win = qWidget<QMainWindow> ();
 
    if (isdefault)
      m_figureToolBar = bar;
 
    if (! visible)
      win->addToolBar (bar);
    else
      {
        QSize sz = bar->sizeHint ();
        QRect r = win->geometry ();
 
        r.adjust (0, -sz.height (), 0, 0);
 
        m_blockUpdates = true;
        set_geometry (r);
        win->addToolBarBreak ();
        win->addToolBar (bar);
        m_blockUpdates = false;
 
        updateBoundingBox (false);
      }
  }
 
  void
  Figure::showCustomToolBar (QToolBar *bar, bool visible)
  {
    QMainWindow *win = qWidget<QMainWindow> ();
 
    if ((! bar->isHidden ()) != visible)
      {
        QSize sz = bar->sizeHint ();
        QRect r = win->geometry ();
 
        if (visible)
          r.adjust (0, -sz.height (), 0, 0);
        else
          r.adjust (0, sz.height (), 0, 0);
 
        m_blockUpdates = true;
        set_geometry (r);
        bar->setVisible (visible);
        m_blockUpdates = false;
 
        updateBoundingBox (false);
      }
  }
 
  void
  Figure::updateContainer (void)
  {
    redraw ();
  }
 
  void
  Figure::figureWindowShown ()
  {
#if defined (HAVE_QSCREEN_DEVICEPIXELRATIO)
    QWindow* window = qWidget<QMainWindow> ()->windowHandle ();
    QScreen* screen = window->screen ();
 
    gh_manager& gh_mgr = m_interpreter.get_gh_manager ();
 
    octave::autolock guard (gh_mgr.graphics_lock ());
 
    figure::properties& fp = properties<figure> ();
    fp.set___device_pixel_ratio__ (screen->devicePixelRatio ());
 
    connect (window, SIGNAL (screenChanged (QScreen*)),
             this, SLOT (screenChanged (QScreen*)));
#endif
  }
 
  void
  Figure::screenChanged (QScreen* screen)
  {
#if defined (HAVE_QSCREEN_DEVICEPIXELRATIO)
    gh_manager& gh_mgr = m_interpreter.get_gh_manager ();
 
    octave::autolock guard (gh_mgr.graphics_lock ());
 
    figure::properties& fp = properties<figure> ();
    double old_dpr = fp.get___device_pixel_ratio__ ();
    double new_dpr = screen->devicePixelRatio ();
    if (old_dpr != new_dpr)
      {
        fp.set___device_pixel_ratio__ (new_dpr);
 
        // For some obscure reason, changing the __device_pixel_ratio__ property
        // from the GUI thread does not necessarily trigger a redraw.  Force it.
        redraw ();
      }
#else
    octave_unused_parameter (screen);
#endif
  }
 
  void
  Figure::enableMouseTracking (void)
  {
    // Enable mouse tracking on every widgets
    m_container->setMouseTracking (true);
    m_container->canvas (m_handle)->qWidget ()->setMouseTracking (true);
    for (auto *w : m_container->findChildren<QWidget*> ())
      w->setMouseTracking (true);
  }
 
}