static const int SETTINGTREE_TOP_OFFSET    = 5; ///< Position of top edge of setting values

	static const int SETTINGTREE_BOTTOM_OFFSET = 5; ///< Position of bottom edge of setting values

	static GameSettings *settings_ptr; ///< Pointer to the game settings being displayed and modified.

	SettingEntry *valuewindow_entry;   ///< If non-NULL, pointer to setting for which a value-entering window has been opened.

	SettingEntry *clicked_entry;       ///< If non-NULL, pointer to a clicked numeric setting (with a depressed left or right button).

	SettingEntry *last_clicked;        ///< If non-NULL, pointer to the last clicked setting.

	SettingEntry *valuedropdown_entry; ///< If non-NULL, pointer to the value for which a dropdown window is currently opened.

	bool closing_dropdown;             ///< True, if the dropdown list is currently closing.

	StringFilter string_filter;        ///< Text filter for settings.

	Scrollbar *vscroll;

	GameSettingsWindow(const WindowDesc *desc) : QueryStringBaseWindow(50)

	{

		static bool first_time = true;

		settings_ptr = &GetGameSettings();

		/* Build up the dynamic settings-array only once per OpenTTD session */

		if (first_time) {

			_settings_main_page.Init();

			first_time = false;

		} else {

			_settings_main_page.FoldAll(); // Close all sub-pages

		}

		this->valuewindow_entry = NULL; // No setting entry for which a entry window is opened

		this->clicked_entry = NULL; // No numeric setting buttons are depressed

		this->last_clicked = NULL;

		this->valuedropdown_entry = NULL;

		this->closing_dropdown = false;

		this->CreateNestedTree(desc);

		this->vscroll = this->GetScrollbar(WID_GS_SCROLLBAR);

		this->FinishInitNested(desc, WN_GAME_OPTIONS_GAME_SETTINGS);

		this->text.Initialize(this->edit_str_buf, this->edit_str_size);

		this->SetFocusedWidget(WID_GS_FILTER);

		this->InvalidateData();

	}

	virtual void UpdateWidgetSize(int widget, Dimension *size, const Dimension &padding, Dimension *fill, Dimension *resize)

	 * @param pe Setting to display help text of, use \c NULL to stop displaying help of the currently displayed setting.

	 */

	void SetDisplayedHelpText(SettingEntry *pe)

	{

		if (this->last_clicked != pe) this->SetDirty();

		this->last_clicked = pe;

	}

	virtual void OnClick(Point pt, int widget, int click_count)

	{

		switch (widget) {

			case WID_GS_EXPAND_ALL:

				_settings_main_page.UnFoldAll();

				this->InvalidateData();

				break;

			case WID_GS_COLLAPSE_ALL:

				_settings_main_page.FoldAll();

				this->InvalidateData();

				break;

		}

		if (widget != WID_GS_OPTIONSPANEL) return;

		uint btn = this->vscroll->GetScrolledRowFromWidget(pt.y, this, WID_GS_OPTIONSPANEL, SETTINGTREE_TOP_OFFSET);

		if (btn == INT_MAX) return;

		uint cur_row = 0;

		SettingEntry *pe = _settings_main_page.FindEntry(btn, &cur_row);

		if (pe == NULL) return;  // Clicked below the last setting of the page

		int x = (_current_text_dir == TD_RTL ? this->width - 1 - pt.x : pt.x) - SETTINGTREE_LEFT_OFFSET - (pe->level + 1) * LEVEL_WIDTH;  // Shift x coordinate

		if (x < 0) return;  // Clicked left of the entry

		if ((pe->flags & SEF_KIND_MASK) == SEF_SUBTREE_KIND) {

			this->SetDisplayedHelpText(NULL);

			pe->d.sub.folded = !pe->d.sub.folded; // Flip 'folded'-ness of the sub-page

			this->InvalidateData();

			return;

		}

		assert((pe->flags & SEF_KIND_MASK) == SEF_SETTING_KIND);

		const SettingDesc *sd = pe->d.entry.setting;

		/* return if action is only active in network, or only settable by server */

		if ((!(sd->save.conv & SLF_NO_NETWORK_SYNC) && _networking && !_network_server && !(sd->desc.flags & SGF_PER_COMPANY)) ||

				((sd->desc.flags & SGF_NETWORK_ONLY) && !_networking) || ((sd->desc.flags & SGF_NO_NETWORK) && _networking)) {

			this->SetDisplayedHelpText(pe);

			return;

	{

		/* Handle editbox input */

		EventState state = ES_NOT_HANDLED;

		if (this->HandleEditBoxKey(WID_GS_FILTER, key, keycode, state) == HEBR_EDITING) {

			this->OnOSKInput(WID_GS_FILTER);

		}

		return state;

	}

	virtual void OnOSKInput(int wid)

	{

		string_filter.SetFilterTerm(this->edit_str_buf);

		this->InvalidateData();

	}

	virtual void OnResize()

	{

		this->vscroll->SetCapacityFromWidget(this, WID_GS_OPTIONSPANEL, SETTINGTREE_TOP_OFFSET + SETTINGTREE_BOTTOM_OFFSET);

	}

};

GameSettings *GameSettingsWindow::settings_ptr = NULL;

static const NWidgetPart _nested_settings_selection_widgets[] = {