            if let Some(ref draw) = self.steep_streets {
                g.redraw(draw);
            }
        }
    }

    fn update_panel(&mut self, ctx: &mut EventCtx, app: &App) {
        self.panel = Panel::new_builder(Widget::col(vec![
            make_zoom_controls(ctx).align_right().padding_right(16),
            self.make_legend(ctx, app)
                .padding(16)
                .bg(ctx.style().panel_bg),