Function MakeNWidget

src/widget.cpp:3282–3311

* Make NWidget from an NWidgetPart. * @param nwid NWidgetPart. * @pre NWidgetPart must not be an attribute NWidgetPart nor WPT_ENDCONTAINER. * @return Pointer to created NWidget. */

 * @return Pointer to created NWidget.
 */
static std::unique_ptr<NWidgetBase> MakeNWidget(const NWidgetPart &nwid)
{
	assert(!IsAttributeWidgetPartType(nwid.type));
	assert(nwid.type != WPT_ENDCONTAINER);

	switch (nwid.type) {
		case NWID_SPACER: return std::make_unique<NWidgetSpacer>(0, 0);

		case WWT_PANEL: [[fallthrough]];
		case WWT_INSET: [[fallthrough]];
		case WWT_FRAME: return std::make_unique<NWidgetBackground>(nwid.type, nwid.u.widget.colour, nwid.u.widget.index);

		case NWID_HORIZONTAL: return std::make_unique<NWidgetHorizontal>(nwid.u.container.flags, nwid.u.container.index);
		case NWID_HORIZONTAL_LTR: return std::make_unique<NWidgetHorizontalLTR>(nwid.u.container.flags, nwid.u.container.index);
		case NWID_VERTICAL: return std::make_unique<NWidgetVertical>(nwid.u.container.flags, nwid.u.container.index);
		case NWID_SELECTION: return std::make_unique<NWidgetStacked>(nwid.u.widget.index);
		case NWID_MATRIX: return std::make_unique<NWidgetMatrix>(nwid.u.widget.colour, nwid.u.widget.index);
		case NWID_VIEWPORT: return std::make_unique<NWidgetViewport>(nwid.u.widget.index);
		case NWID_LAYER: return std::make_unique<NWidgetLayer>(nwid.u.widget.index);

		case NWID_HSCROLLBAR: [[fallthrough]];
		case NWID_VSCROLLBAR: return std::make_unique<NWidgetScrollbar>(nwid.type, nwid.u.widget.colour, nwid.u.widget.index);

		case WPT_FUNCTION: return nwid.u.func_ptr();

		default:
			assert((nwid.type & WWT_MASK) < WWT_LAST || (nwid.type & WWT_MASK) == NWID_BUTTON_DROPDOWN);
			return std::make_unique<NWidgetLeaf>(nwid.type, nwid.u.widget.colour, nwid.u.widget.index, WidgetData{}, STR_NULL);
	}
}

/**
 * Construct a single nested widget in \a *dest from its parts.