Wayland: simplify handling of tall menu windows

1 files changed, 26 insertions, 83 deletions

diff --git a/src/drivers/Wayland/Fl_Wayland_Window_Driver.cxx b/src/drivers/Wayland/Fl_Wayland_Window_Driver.cxx
index c9a0cbbf8..75d3f05b7 100644
--- a/src/drivers/Wayland/Fl_Wayland_Window_Driver.cxx
+++ b/src/drivers/Wayland/Fl_Wayland_Window_Driver.cxx
@@ -1347,13 +1347,20 @@ bool Fl_Wayland_Window_Driver::process_menu_or_tooltip(struct wld_window *new_wi
     xdg_positioner_set_anchor_rect(positioner, popup_x, 0, 1, 1);
     popup_y++;
   }
-  int V, screen_H;
-  Fl::screen_work_area(V, V, V, screen_H, origin_win->screen_num());
-  // Under KWIN, we need to have in screen_H the size of the current screen's work-area.
-  // We get this exactly only when there's a single screen. Otherwise, we get the screen height.
-  bool tall_kde = (pWindow->h() > screen_H) &&
-    (Fl_Wayland_Screen_Driver::compositor == Fl_Wayland_Screen_Driver::KWIN);
-  xdg_positioner_set_size(positioner, pWindow->w() * f , (tall_kde ? screen_H : pWindow->h()) * f );
+  int positioner_H = pWindow->h();
+  if (Fl_Wayland_Screen_Driver::compositor == Fl_Wayland_Screen_Driver::KWIN) {
+    // Under KWIN, limiting the height of the positioner to the work area height
+    // results in tall popup windows starting at the top of the screen, what we want.
+    // Unfortunately, we know the work area height exactly only for single-screen systems,
+    // otherwise FLTK returns work area height == screen height. In that case we estimate
+    // work area height ≈ screen height - 40.
+    int V, work_area_H, screen_H;
+    Fl::screen_work_area(V, V, V, work_area_H, origin_win->screen_num());
+    Fl::screen_xywh(V, V, V, screen_H, origin_win->screen_num());
+    if (work_area_H == screen_H) work_area_H -= 40;
+    if (positioner_H > work_area_H) positioner_H = work_area_H;
+  }
+  xdg_positioner_set_size(positioner, pWindow->w() * f , positioner_H * f );
   xdg_positioner_set_anchor(positioner, XDG_POSITIONER_ANCHOR_BOTTOM_LEFT);
   xdg_positioner_set_gravity(positioner, XDG_POSITIONER_GRAVITY_BOTTOM_RIGHT);
   // prevent menuwindow from expanding beyond display limits
@@ -2012,83 +2019,19 @@ void Fl_Wayland_Window_Driver::subRect(cairo_rectangle_int_t *r) {
 
 void Fl_Wayland_Window_Driver::reposition_menu_window(int x, int y) {
   if (y == pWindow->y()) return;
-  if (Fl_Wayland_Screen_Driver::compositor == Fl_Wayland_Screen_Driver::KWIN) {
-    // The KWin compositor refuses to position a popup such that it extends above
-    // the top of the screen. That's no longer true with version 6 of KWIN.
-    // Instead of sliding the popup window
-    // on the display, we slide the drawing inside the fixed popup via
-    // member variable offset_y of the menuwindow class, and we redraw the popup
-    // content. It's also useful to make such tall popup window transparent.
-    *Fl_Window_Driver::menu_offset_y(pWindow) += (y - pWindow->y());
-    struct wld_window *xid = fl_wl_xid(pWindow);
-    wl_surface_set_opaque_region(xid->wl_surface, NULL);
-    if (xid->buffer) memset(xid->buffer->draw_buffer.buffer, 0,
-                            xid->buffer->draw_buffer.data_size);
-    //printf("offset_y=%d\n", *Fl_Window_Driver::menu_offset_y(pWindow));
-    this->y(y);
-    pWindow->redraw();
-    return;
-  }
-  struct wld_window * xid_menu = fl_wl_xid(pWindow);
-//printf("reposition %dx%d[cur=%d] menu->state=%d\n", x, y, pWindow->y(), xid_menu->state);
-  struct xdg_popup *old_popup = xid_menu->xdg_popup;
-  struct xdg_surface *old_xdg = xid_menu->xdg_surface;
-  struct wl_surface *old_surface = xid_menu->wl_surface;
-  // menu_origin will be the parent of the processed menu window
-  Fl_Window *menu_origin = Fl_Window_Driver::menu_title(pWindow);
-  if (!menu_origin) menu_origin = Fl_Window_Driver::menu_leftorigin(pWindow);
-  if (!menu_origin) menu_origin = Fl_Window_Driver::menu_parent();
-  if (Fl_Window_Driver::menu_title(pWindow) && !Fl_Window_Driver::menu_bartitle(pWindow) &&
-      !Fl_Window_Driver::menu_leftorigin(pWindow)) {
-    // occurs with tall popup menu
-    menu_origin = Fl_Window_Driver::menu_parent();
-  }
-  // create a new popup at position (x,y) and display it above the current one
-  Fl_Wayland_Screen_Driver *scr_driver = (Fl_Wayland_Screen_Driver*)Fl::screen_driver();
-  xid_menu->wl_surface = wl_compositor_create_surface(scr_driver->wl_compositor);
-  wl_surface_add_listener(xid_menu->wl_surface, &surface_listener, xid_menu);
-  xid_menu->xdg_surface = xdg_wm_base_get_xdg_surface(scr_driver->xdg_wm_base,
-                                                      xid_menu->wl_surface);
-  xdg_surface_add_listener(xid_menu->xdg_surface, &xdg_surface_listener, xid_menu);
-  struct xdg_positioner *positioner = xdg_wm_base_create_positioner(scr_driver->xdg_wm_base);
-  struct wld_window * parent_xid = fl_wl_xid(menu_origin);
-  float f = Fl::screen_scale(Fl_Window_Driver::menu_parent()->screen_num());
-  int popup_x = x * f, popup_y = y * f + xid_menu->state;
-  if (menu_origin->menu_window() && driver(menu_origin)->popup_window()) {
-    popup_x -= menu_origin->x() * f;
-    popup_y -= menu_origin->y() * f;
-  }
-  if (popup_x >= menu_origin->w() * f) popup_x = menu_origin->w() * f - 1;
-  if (parent_xid->kind == DECORATED) {
-    libdecor_frame_translate_coordinate(parent_xid->frame, popup_x, popup_y,
-                                        &popup_x, &popup_y);
-  }
-  xdg_positioner_set_anchor_rect(positioner, popup_x, 0, 1, 1);
-  xdg_positioner_set_size(positioner, pWindow->w() * f , pWindow->h() * f );
-  xdg_positioner_set_anchor(positioner, XDG_POSITIONER_ANCHOR_TOP_LEFT);
-  xdg_positioner_set_gravity(positioner, XDG_POSITIONER_GRAVITY_BOTTOM_RIGHT);
-  xdg_positioner_set_constraint_adjustment(positioner,
-                                           XDG_POSITIONER_CONSTRAINT_ADJUSTMENT_SLIDE_X);
-  xdg_positioner_set_offset(positioner, 0, popup_y);
-  xid_menu->xdg_popup = xdg_surface_get_popup(xid_menu->xdg_surface, parent_xid->xdg_surface,
-                                              positioner);
-  xdg_positioner_destroy(positioner);
-  struct win_positioner *win_pos = new struct win_positioner;
-  win_pos->window = xid_menu;
-  win_pos->x = popup_x;
-  win_pos->y = popup_y;
-  win_pos->child_popup = NULL;
-  xdg_popup_add_listener(xid_menu->xdg_popup, &popup_listener, win_pos);
-  wl_surface_commit(xid_menu->wl_surface);
-  wl_display_roundtrip(Fl_Wayland_Screen_Driver::wl_display); // necessary with sway
-  // delete the previous popup
-  struct win_positioner *old_win_pos =
-    (struct win_positioner*)xdg_popup_get_user_data(old_popup);
-  xdg_popup_destroy(old_popup);
-  delete old_win_pos;
-  xdg_surface_destroy(old_xdg);
-  destroy_surface_caution_pointer_focus(old_surface, scr_driver->seat);
+  // The top of the tall popup window was positioned at the top of the screen
+  // Instead of sliding up the popup window on the display, we slide up the
+  // drawing inside the fixed popup via member variable offset_y of the
+  // menuwindow class, and we redraw the popup content.
+  // It's also useful to make such tall popup window transparent.
+  *Fl_Window_Driver::menu_offset_y(pWindow) += (y - pWindow->y());
+  struct wld_window *xid = fl_wl_xid(pWindow);
+  wl_surface_set_opaque_region(xid->wl_surface, NULL);
+  if (xid->buffer) memset(xid->buffer->draw_buffer.buffer, 0,
+                          xid->buffer->draw_buffer.data_size);
+  //printf("offset_y=%d\n", *Fl_Window_Driver::menu_offset_y(pWindow));
   this->y(y);
+  pWindow->redraw();
 }