Function EnsureVisibleCaption

src/window.cpp:2062–2087

* Make sure at least a part of the caption bar is still visible by moving * the window if necessary. * @param w The window to check. * @param nx The proposed new x-location of the window. * @param ny The proposed new y-location of the window. */

 * @param ny The proposed new y-location of the window.
 */
static void EnsureVisibleCaption(Window *w, int nx, int ny)
{
	/* Search for the title bar rectangle. */
	const NWidgetBase *caption = w->nested_root->GetWidgetOfType(WWT_CAPTION);
	if (caption != nullptr) {
		const Rect caption_rect = caption->GetCurrentRect();

		const int min_visible = caption_rect.Height();

		/* Make sure the window doesn't leave the screen */
		nx = Clamp(nx, min_visible - caption_rect.right, _screen.width - min_visible - caption_rect.left);
		ny = Clamp(ny, 0, _screen.height - min_visible);

		/* Make sure the title bar isn't hidden behind the main tool bar or the status bar. */
		PreventHiding(&nx, &ny, caption_rect, FindWindowById(WC_MAIN_TOOLBAR, 0), w->left, PHD_DOWN);
		PreventHiding(&nx, &ny, caption_rect, FindWindowById(WC_STATUS_BAR,   0), w->left, PHD_UP);
	}

	if (w->viewport != nullptr) {
		w->viewport->left += nx - w->left;
		w->viewport->top  += ny - w->top;
	}

	w->left = nx;
	w->top  = ny;
}

/**
 * Resize the window.