wxgtk/ui.cpp

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/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 2020 Ian McInerney <Ian.S.McInerney at ieee.org>
 * Copyright The KiCad Developers, see AUTHORS.txt for contributors.
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 */
 
#include <kiplatform/ui.h>
 
#include <wx/choice.h>
#include <wx/dataview.h>
#include <wx/dialog.h>
#include <wx/nonownedwnd.h>
#include <wx/settings.h>
#include <wx/window.h>
#include <wx/log.h>
 
#include <gtk/gtk.h>
#include <gdk/gdk.h>
 
#ifdef GDK_WINDOWING_X11
#include <gdk/gdkx.h>
#endif
 
#ifdef GDK_WINDOWING_WAYLAND
#include <gdk/gdkwayland.h>
#endif
 
#ifdef KICAD_WAYLAND
#include "wayland-pointer-constraints-unstable-v1.h"
#endif
 
// Set WXTRACE=KICAD_WAYLAND to see logs
const wxString traceWayland = wxS( "KICAD_WAYLAND" );
 
 
bool KIPLATFORM::UI::IsDarkTheme()
{
    wxColour bg = wxSystemSettings::GetColour( wxSYS_COLOUR_WINDOW );
 
    // Weighted W3C formula
    double brightness = ( bg.Red() / 255.0 ) * 0.299 +
                        ( bg.Green() / 255.0 ) * 0.587 +
                        ( bg.Blue() / 255.0 ) * 0.117;
 
    return brightness < 0.5;
}
 
 
wxColour KIPLATFORM::UI::GetDialogBGColour()
{
    return wxSystemSettings::GetColour( wxSYS_COLOUR_BTNFACE );
}
 
 
void KIPLATFORM::UI::GetInfoBarColours( wxColour& aFgColour, wxColour& aBgColour )
{
    // The GTK3.24 way of getting the colours is to use the style context
    // Earlier GTKs should be able to use the system settings
#if( GTK_CHECK_VERSION( 3, 24, 0 ) )
    GdkRGBA*         rgba;
    GtkWidgetPath*   path = gtk_widget_path_new();
    GtkStyleContext* sc = gtk_style_context_new();
 
    gtk_widget_path_append_type( path, GTK_TYPE_WINDOW );
    gtk_widget_path_iter_set_object_name( path, -1, "infobar" );
    gtk_widget_path_iter_add_class( path, -1, "info" );
 
    gtk_style_context_set_path( sc, path );
    gtk_style_context_set_state( sc, GTK_STATE_FLAG_NORMAL );
 
    gtk_style_context_get( sc, GTK_STATE_FLAG_NORMAL, "background-color", &rgba, NULL );
    aBgColour = wxColour( *rgba );
    gdk_rgba_free( rgba );
 
    gtk_style_context_get( sc, GTK_STATE_FLAG_NORMAL, "color", &rgba, NULL );
    aFgColour = wxColour( *rgba );
    gdk_rgba_free( rgba );
 
    // Some GTK themes use the plain infobar style, but if they don't, the background alpha
    // is generally 0. In this case, try the revealer and box as these are used for Adwaita
    // and other themes.
    if( aBgColour.Alpha() == 0 )
    {
        gtk_widget_path_append_type( path, G_TYPE_NONE );
        gtk_widget_path_iter_set_object_name( path, -1, "revealer" );
        gtk_widget_path_append_type( path, G_TYPE_NONE );
        gtk_widget_path_iter_set_object_name( path, -1, "box" );
 
        gtk_style_context_set_path( sc, path );
        gtk_style_context_set_state( sc, GTK_STATE_FLAG_NORMAL );
 
        gtk_style_context_get( sc, GTK_STATE_FLAG_NORMAL, "background-color", &rgba, NULL );
        aBgColour = wxColour( *rgba );
        gdk_rgba_free( rgba );
 
        gtk_style_context_get( sc, GTK_STATE_FLAG_NORMAL, "color", &rgba, NULL );
        aFgColour = wxColour( *rgba );
        gdk_rgba_free( rgba );
    }
 
    gtk_widget_path_free( path );
    g_object_unref( sc );
 
#else
    aBgColour = wxSystemSettings::GetColour( wxSYS_COLOUR_INFOBK );
    aFgColour = wxSystemSettings::GetColour( wxSYS_COLOUR_INFOTEXT );
#endif
 
}
 
 
void KIPLATFORM::UI::ForceFocus( wxWindow* aWindow )
{
    aWindow->SetFocus();
 
    // On GTK, SetFocus() on a dialog may not be sufficient to receive keyboard events
    // (like ESC for closing). We need to ensure the window is presented and active.
    // Find the top-level window and present it to ensure keyboard focus.
    wxWindow* tlw = aWindow;
 
    while( tlw && !tlw->IsTopLevel() )
        tlw = tlw->GetParent();
 
    if( tlw )
    {
        GtkWidget* widget = static_cast<GtkWidget*>( tlw->GetHandle() );
 
        if( widget && GTK_IS_WINDOW( widget ) )
            gtk_window_present( GTK_WINDOW( widget ) );
    }
}
 
 
bool KIPLATFORM::UI::IsWindowActive( wxWindow* aWindow )
{
    if( !aWindow )
        return false;
 
    GtkWindow* window = GTK_WINDOW( aWindow->GetHandle() );
 
    if( window )
        return gtk_window_is_active( window );
 
    // We shouldn't really ever reach this point
    return false;
}
 
 
void KIPLATFORM::UI::EnsureVisible( wxWindow* aWindow )
{
    // Not needed on this platform
}
 
 
void KIPLATFORM::UI::StabilizeWindowPosition( wxWindow* aWindow )
{
    if( !aWindow )
        return;
 
    GtkWidget* widget = static_cast<GtkWidget*>( aWindow->GetHandle() );
 
    if( widget && GTK_IS_WINDOW( widget ) )
        gtk_window_set_gravity( GTK_WINDOW( widget ), GDK_GRAVITY_STATIC );
}
 
 
void KIPLATFORM::UI::ReparentModal( wxNonOwnedWindow* aWindow )
{
    // Not needed on this platform
}
 
 
void KIPLATFORM::UI::ReparentWindow( wxNonOwnedWindow* aWindow, wxTopLevelWindow* aParent )
{
    // Not needed on this platform (only relevant for macOS child window ordering)
}
 
 
void KIPLATFORM::UI::FixupCancelButtonCmdKeyCollision( wxWindow *aWindow )
{
    // Not needed on this platform
}
 
 
bool KIPLATFORM::UI::IsStockCursorOk( wxStockCursor aCursor )
{
    switch( aCursor )
    {
    case wxCURSOR_BULLSEYE:
    case wxCURSOR_HAND:
    case wxCURSOR_ARROW:
    case wxCURSOR_BLANK:
        return true;
    default:
        return false;
    }
}
 

static void disable_area_apply_attributes_cb( GtkWidget* pItem, gpointer userdata )
{
    // GTK needs this enormous chain to get the actual type of item that we want
    GtkMenuItem*   pMenuItem   = GTK_MENU_ITEM( pItem );
    GtkWidget*     child       = gtk_bin_get_child( GTK_BIN( pMenuItem ) );
    GtkCellView*   pCellView   = GTK_CELL_VIEW( child );
    GtkCellLayout* pCellLayout = GTK_CELL_LAYOUT( pCellView );
    GtkCellArea*   pCellArea   = gtk_cell_layout_get_area( pCellLayout );
 
    g_signal_handlers_block_matched( pCellArea, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, userdata );
}
 
 
void KIPLATFORM::UI::LargeChoiceBoxHack( wxChoice* aChoice )
{
    AtkObject* atkObj = gtk_combo_box_get_popup_accessible( GTK_COMBO_BOX( aChoice->m_widget ) );
 
    if( !atkObj || !GTK_IS_ACCESSIBLE( atkObj ) )
        return;
 
    GtkWidget* widget = gtk_accessible_get_widget( GTK_ACCESSIBLE( atkObj ) );
 
    if( !widget || !GTK_IS_MENU( widget ) )
        return;
 
    GtkMenu* menu = GTK_MENU( widget );
 
    gtk_container_foreach( GTK_CONTAINER( menu ), disable_area_apply_attributes_cb, menu );
}
 
 
void KIPLATFORM::UI::EllipsizeChoiceBox( wxChoice* aChoice )
{
    // This function is based on the code inside the function post_process_ui in
    // gtkfilechooserwidget.c
    GList* cells = gtk_cell_layout_get_cells( GTK_CELL_LAYOUT( aChoice->m_widget ) );
 
    if( !cells )
        return;
 
    GtkCellRenderer* cell = (GtkCellRenderer*) cells->data;
 
    if( !cell )
        return;
 
    g_object_set( G_OBJECT( cell ), "ellipsize", PANGO_ELLIPSIZE_END, nullptr );
 
    // Only the list of cells must be freed, the renderer isn't ours to free
    g_list_free( cells );
}
 
 
double KIPLATFORM::UI::GetPixelScaleFactor( const wxWindow* aWindow )
{
    double val = 1.0;
 
    GtkWidget* widget = static_cast<GtkWidget*>( aWindow->GetHandle() );
 
    if( widget && gtk_check_version( 3, 10, 0 ) == nullptr )
        val = gtk_widget_get_scale_factor( widget );
 
    return val;
}
 
 
double KIPLATFORM::UI::GetContentScaleFactor( const wxWindow* aWindow )
{
    // TODO: Do we need something different here?
    return GetPixelScaleFactor( aWindow );
}
 
 
wxSize KIPLATFORM::UI::GetUnobscuredSize( const wxWindow* aWindow )
{
    return wxSize( aWindow->GetSize().GetX() - wxSystemSettings::GetMetric( wxSYS_VSCROLL_X ),
                   aWindow->GetSize().GetY() - wxSystemSettings::GetMetric( wxSYS_HSCROLL_Y ) );
}
 
 
void KIPLATFORM::UI::SetOverlayScrolling( const wxWindow* aWindow, bool overlay )
{
    gtk_scrolled_window_set_overlay_scrolling( GTK_SCROLLED_WINDOW( aWindow->GetHandle() ),
                                               overlay );
}
 
 
bool KIPLATFORM::UI::AllowIconsInMenus()
{
    gboolean allowed = 1;
 
    g_object_get( gtk_settings_get_default(), "gtk-menu-images", &allowed, NULL );
 
    return !!allowed;
}
 
 
#if defined( GDK_WINDOWING_WAYLAND ) && defined( KICAD_WAYLAND )
 
static bool wayland_warp_pointer( GtkWidget* aWidget, GdkDisplay* aDisplay, GdkWindow* aWindow,
                                  GdkDevice* aPtrDev, int aX, int aY );
 
// GDK doesn't know if we've moved the cursor using Wayland pointer constraints.
// So emulate the actual position here
static wxPoint s_warped_from;
static wxPoint s_warped_to;
 
wxPoint KIPLATFORM::UI::GetMousePosition()
{
    wxPoint wx_pos = wxGetMousePosition();
 
    if( wx_pos == s_warped_from )
    {
        wxLogTrace( traceWayland, wxS( "Faked mouse pos %d %d -> %d %d" ), wx_pos.x, wx_pos.y,
                    s_warped_to.x, s_warped_to.y );
 
        return s_warped_to;
    }
    else
    {
        // Mouse has moved
        s_warped_from = wxPoint();
        s_warped_to = wxPoint();
    }
 
    return wx_pos;
}
 
#endif
 
 
bool KIPLATFORM::UI::WarpPointer( wxWindow* aWindow, int aX, int aY )
{
    if( !wxGetEnv( wxT( "WAYLAND_DISPLAY" ), nullptr ) )
    {
        aWindow->WarpPointer( aX, aY );
        return true;
    }
    else
    {
        GtkWidget* widget = static_cast<GtkWidget*>( aWindow->GetHandle() );
 
        GdkDisplay* disp = gtk_widget_get_display( widget );
        GdkSeat*    seat = gdk_display_get_default_seat( disp );
        GdkDevice*  ptrdev = gdk_seat_get_pointer( seat );
 
#if defined( GDK_WINDOWING_WAYLAND ) && defined( KICAD_WAYLAND )
        if( GDK_IS_WAYLAND_DISPLAY( disp ) )
        {
            wxPoint    initialPos = wxGetMousePosition();
            GdkWindow* win = aWindow->GTKGetDrawingWindow();
 
            if( wayland_warp_pointer( widget, disp, win, ptrdev, aX, aY ) )
            {
                s_warped_from = initialPos;
                s_warped_to = aWindow->ClientToScreen( wxPoint( aX, aY ) );
 
                wxLogTrace( traceWayland, wxS( "Set warped from %d %d to %d %d" ), s_warped_from.x,
                            s_warped_from.y, s_warped_to.x, s_warped_to.y );
 
                return true;
            }
 
            wxLogTrace( traceWayland, wxS( "*** Warp to %d %d failed ***" ), aX, aY );
 
            return false;
        }
#endif
#ifdef GDK_WINDOWING_X11
        if( GDK_IS_X11_DISPLAY( disp ) )
        {
            GdkWindow* win = gdk_device_get_window_at_position( ptrdev, nullptr, nullptr );
            GdkCursor* blank_cursor = gdk_cursor_new_for_display( disp, GDK_BLANK_CURSOR );
            GdkCursor* cur_cursor = gdk_window_get_cursor( win );
 
            if( cur_cursor )
                g_object_ref( cur_cursor );
 
            gdk_window_set_cursor( win, blank_cursor );
            aWindow->WarpPointer( aX, aY );
            gdk_window_set_cursor( win, cur_cursor );
 
            if( cur_cursor )
                g_object_unref( cur_cursor );
 
            if( blank_cursor )
                g_object_unref( blank_cursor );
 
            return true;
        }
#endif
    }
 
    return false;
}
 
 
void KIPLATFORM::UI::ImmControl( wxWindow* aWindow, bool aEnable )
{
}
 
 
void KIPLATFORM::UI::ImeNotifyCancelComposition( wxWindow* aWindow )
{
    wxWindowGTK* win = static_cast<wxWindowGTK*>( aWindow );
    if( win )
    {
        GtkIMContext* imContext = win->m_imContext;
        if( imContext )
        {
            gtk_im_context_focus_out( imContext );
        }
    }
}
 
 
void KIPLATFORM::UI::SetFloatLevel( wxWindow* aWindow )
{
}
 
 
void KIPLATFORM::UI::ReleaseChildWindow( wxNonOwnedWindow* aWindow )
{
    // Not needed on this platform
}
 
 
void KIPLATFORM::UI::AllowNetworkFileSystems( wxDialog* aDialog )
{
    GtkWidget* widget = static_cast<GtkWidget*>( aDialog->GetHandle() );
 
    if( widget && GTK_IS_FILE_CHOOSER( widget ) )
        gtk_file_chooser_set_local_only( GTK_FILE_CHOOSER( widget ), FALSE );
}
 
 
void KIPLATFORM::UI::CancelPendingScroll( wxDataViewCtrl* aCtrl )
{
    if( !aCtrl )
        return;
 
    GtkWidget* widget = aCtrl->GtkGetTreeView();
 
    if( !widget || !GTK_IS_TREE_VIEW( widget ) )
        return;
 
    GtkTreeView* view = GTK_TREE_VIEW( widget );
 
    // Need a live model and rbtree for the assertions in scroll_to_cell.
    if( !gtk_tree_view_get_model( view ) )
        return;
 
    GtkTreeViewColumn* column = gtk_tree_view_get_column( view, 0 );
 
    if( !column )
        return;
 
    // A column-only scroll_to_cell enters GTK's deferred-scroll path, which frees
    // priv->scroll_to_path and only installs scroll_to_column.  That breaks the race
    // where validate_visible_area dereferences a stale row reference after a model
    // reset.  The deferred branch is taken when the widget is not yet allocated, when
    // alloc is pending, or when rows are invalid -- queue_resize forces the latter so
    // a steady-state widget also takes that branch and actually clears the reference.
    gtk_widget_queue_resize( widget );
    gtk_tree_view_scroll_to_cell( view, nullptr, column, FALSE, 0.0, 0.0 );
}
 
//
// **** Wayland hacks ahead ****
//
 
#if defined( GDK_WINDOWING_WAYLAND ) && defined( KICAD_WAYLAND )
 
static bool                               s_wl_initialized = false;
static struct wl_compositor*              s_wl_compositor = NULL;
static struct zwp_pointer_constraints_v1* s_wl_pointer_constraints = NULL;
static struct zwp_confined_pointer_v1*    s_wl_confined_pointer = NULL;
static struct wl_region*                  s_wl_confinement_region = NULL;
static bool                               s_wl_locked_flag = false;
 
static void handle_global( void* data, struct wl_registry* registry, uint32_t name,
                           const char* interface, uint32_t version )
{
    wxLogTrace( traceWayland, "handle_global received %s name %u version %u", interface,
                (unsigned int) name, (unsigned int) version );
 
    if( strcmp( interface, wl_compositor_interface.name ) == 0 )
    {
        s_wl_compositor = static_cast<wl_compositor*>(
                wl_registry_bind( registry, name, &wl_compositor_interface, version ) );
    }
    else if( strcmp( interface, zwp_pointer_constraints_v1_interface.name ) == 0 )
    {
        s_wl_pointer_constraints = static_cast<zwp_pointer_constraints_v1*>( wl_registry_bind(
                registry, name, &zwp_pointer_constraints_v1_interface, version ) );
    }
}
 
static void handle_global_remove( void*, struct wl_registry*, uint32_t name )
{
    wxLogTrace( traceWayland, "handle_global_remove name %u", (unsigned int) name );
}
 
static const struct wl_registry_listener registry_listener = {
    .global = handle_global,
    .global_remove = handle_global_remove,
};
 
static void confined_handler( void* data, struct zwp_confined_pointer_v1* zwp_confined_pointer_v1 )
{
    wxLogTrace( traceWayland, wxS( "Pointer confined" ) );
}
 
static void unconfined_handler( void*                           data,
                                struct zwp_confined_pointer_v1* zwp_confined_pointer_v1 )
{
    wxLogTrace( traceWayland, wxS( "Pointer unconfined" ) );
}
 
static const struct zwp_confined_pointer_v1_listener confined_pointer_listener = {
    .confined = confined_handler,
    .unconfined = unconfined_handler
};
 
static void locked_handler( void* data, struct zwp_locked_pointer_v1* zwp_locked_pointer_v1 )
{
    s_wl_locked_flag = true;
    wxLogTrace( traceWayland, wxS( "Pointer locked" ) );
}
 
static void unlocked_handler( void* data, struct zwp_locked_pointer_v1* zwp_locked_pointer_v1 )
{
    wxLogTrace( traceWayland, wxS( "Pointer unlocked" ) );
}
 
static const struct zwp_locked_pointer_v1_listener locked_pointer_listener = {
    .locked = locked_handler,
    .unlocked = unlocked_handler
};
 

static void initialize_wayland( wl_display* wldisp )
{
    if( s_wl_initialized )
    {
        return;
    }
 
    struct wl_registry* registry = wl_display_get_registry( wldisp );
    wl_registry_add_listener( registry, &registry_listener, NULL );
    wl_display_roundtrip( wldisp );
    s_wl_initialized = true;
}
 
 
struct zwp_locked_pointer_v1* s_wl_locked_pointer = NULL;
 
static int s_after_paint_handler_id = 0;
 
static void on_frame_clock_after_paint( GdkFrameClock* clock, GtkWidget* widget )
{
    if( s_wl_locked_pointer )
    {
        zwp_locked_pointer_v1_destroy( s_wl_locked_pointer );
        s_wl_locked_pointer = NULL;
 
        wxLogTrace( traceWayland, wxS( "after-paint: locked_pointer destroyed" ) );
 
        g_signal_handler_disconnect( (gpointer) clock, s_after_paint_handler_id );
        s_after_paint_handler_id = 0;
 
        // restore confinement
        if( s_wl_confinement_region != NULL )
        {
            wxLogTrace( traceWayland, wxS( "after-paint: Restoring confinement" ) );
 
            GdkDisplay* disp = gtk_widget_get_display( widget );
            GdkSeat*    seat = gdk_display_get_default_seat( disp );
            GdkDevice*  ptrdev = gdk_seat_get_pointer( seat );
            GdkWindow*  window = gtk_widget_get_window( widget );
 
            wl_display* wldisp = gdk_wayland_display_get_wl_display( disp );
            wl_surface* wlsurf = gdk_wayland_window_get_wl_surface( window );
            wl_pointer* wlptr = gdk_wayland_device_get_wl_pointer( ptrdev );
 
            s_wl_confined_pointer = zwp_pointer_constraints_v1_confine_pointer(
                    s_wl_pointer_constraints, wlsurf, wlptr, s_wl_confinement_region,
                    ZWP_POINTER_CONSTRAINTS_V1_LIFETIME_ONESHOT );
 
            wl_display_roundtrip( wldisp );
        }
    }
}
 
 
static bool wayland_warp_pointer( GtkWidget* aWidget, GdkDisplay* aDisplay, GdkWindow* aWindow,
                                  GdkDevice* aPtrDev, int aX, int aY )
{
    wl_display* wldisp = gdk_wayland_display_get_wl_display( aDisplay );
    wl_surface* wlsurf = gdk_wayland_window_get_wl_surface( aWindow );
    wl_pointer* wlptr = gdk_wayland_device_get_wl_pointer( aPtrDev );
 
    if( s_after_paint_handler_id )
    {
        // Previous paint not done yet
        wxLogTrace( traceWayland, wxS( "Not warping: after-paint pending" ) );
        return false;
    }
 
    initialize_wayland( wldisp );
 
    if( s_wl_locked_pointer )
    {
        // This shouldn't happen but let's be safe
        wxLogTrace( traceWayland, wxS( "** Destroying previous locked_pointer **" ) );
        zwp_locked_pointer_v1_destroy( s_wl_locked_pointer );
        wl_display_roundtrip( wldisp );
        s_wl_locked_pointer = NULL;
    }
 
    // wl_surface_commit causes an assert on GNOME, but has to be called on KDE
    // before destroying the locked pointer, so wait until GDK commits the surface.
    GdkFrameClock* frame_clock = gdk_window_get_frame_clock( aWindow );
    s_after_paint_handler_id = g_signal_connect_after(
            frame_clock, "after-paint", G_CALLBACK( on_frame_clock_after_paint ), aWidget );
 
    // temporary disable confinement to allow pointer warping
    if( s_wl_confinement_region && s_wl_confined_pointer )
    {
        zwp_confined_pointer_v1_destroy( s_wl_confined_pointer );
        wl_display_roundtrip( wldisp );
        s_wl_confined_pointer = NULL;
    }
 
    s_wl_locked_flag = false;
 
    s_wl_locked_pointer =
            zwp_pointer_constraints_v1_lock_pointer( s_wl_pointer_constraints, wlsurf, wlptr, NULL,
                                                     ZWP_POINTER_CONSTRAINTS_V1_LIFETIME_ONESHOT );
 
    zwp_locked_pointer_v1_add_listener(s_wl_locked_pointer, &locked_pointer_listener, NULL);
 
    gint wx, wy;
    gtk_widget_translate_coordinates( aWidget, gtk_widget_get_toplevel( aWidget ), 0, 0, &wx, &wy );
 
    zwp_locked_pointer_v1_set_cursor_position_hint( s_wl_locked_pointer, wl_fixed_from_int( aX + wx ),
                                                    wl_fixed_from_int( aY + wy ) );
 
    // Don't call wl_surface_commit, wait for GDK because of an assert on GNOME.
    wl_display_roundtrip( wldisp ); // To receive "locked" event.
    gtk_widget_queue_draw( aWidget ); // Needed on some GNOME environment to trigger
                                      // the "after-paint" event handler.
 
    return s_wl_locked_flag;
}
 
 
bool KIPLATFORM::UI::InfiniteDragPrepareWindow( wxWindow* aWindow )
{
    wxLogTrace( traceWayland, wxS( "InfiniteDragPrepareWindow" ) );
 
    GtkWidget*  widget = static_cast<GtkWidget*>( aWindow->GetHandle() );
    GdkDisplay* disp = gtk_widget_get_display( widget );
 
    if( GDK_IS_WAYLAND_DISPLAY( disp ) )
    {
        if( s_wl_confined_pointer != NULL )
        {
            KIPLATFORM::UI::InfiniteDragReleaseWindow();
        }
 
        GdkSeat*   seat = gdk_display_get_default_seat( disp );
        GdkDevice* ptrdev = gdk_seat_get_pointer( seat );
        GdkWindow* win = aWindow->GTKGetDrawingWindow();
 
        wl_display* wldisp = gdk_wayland_display_get_wl_display( disp );
        wl_surface* wlsurf = gdk_wayland_window_get_wl_surface( win );
        wl_pointer* wlptr = gdk_wayland_device_get_wl_pointer( ptrdev );
 
        initialize_wayland( wldisp );
 
        gint x, y, width, height;
        gdk_window_get_geometry( gdk_window_get_toplevel( win ), &x, &y, &width, &height );
 
        wxLogTrace( traceWayland, wxS( "Confine region: %d %d %d %d" ), x, y, width, height );
 
        s_wl_confinement_region = wl_compositor_create_region( s_wl_compositor );
        wl_region_add( s_wl_confinement_region, x, y, width, height );
 
        s_wl_confined_pointer = zwp_pointer_constraints_v1_confine_pointer(
                s_wl_pointer_constraints, wlsurf, wlptr, s_wl_confinement_region,
                ZWP_POINTER_CONSTRAINTS_V1_LIFETIME_ONESHOT );
 
        zwp_confined_pointer_v1_add_listener( s_wl_confined_pointer, &confined_pointer_listener,
                                              NULL );
 
        wl_display_roundtrip( wldisp );
    }
    else if( wxGetEnv( wxT( "WAYLAND_DISPLAY" ), nullptr ) )
    {
        // Not working under XWayland
        return false;
    }
 
    return true;
};
 
 
void KIPLATFORM::UI::InfiniteDragReleaseWindow()
{
    wxLogTrace( traceWayland, wxS( "InfiniteDragReleaseWindow" ) );
 
    if( s_wl_confined_pointer )
    {
        zwp_confined_pointer_v1_destroy( s_wl_confined_pointer );
        s_wl_confined_pointer = NULL;
    }
 
    if( s_wl_confinement_region )
    {
        wl_region_destroy( s_wl_confinement_region );
        s_wl_confinement_region = NULL;
    }
};
 
 
#else // No Wayland support
 
 
bool KIPLATFORM::UI::InfiniteDragPrepareWindow( wxWindow* aWindow )
{
    // Not working under XWayland
    return !wxGetEnv( wxT( "WAYLAND_DISPLAY" ), nullptr );
};
 
 
void KIPLATFORM::UI::InfiniteDragReleaseWindow()
{
    // Not needed on X11
};
 
 
wxPoint KIPLATFORM::UI::GetMousePosition()
{
    return wxGetMousePosition();
}
 
 
#endif