Now have a nice panel to hold all the UI panels we'll use later.

panel.hpp

@@ -0,0 +1,39 @@
+#pragma once
+#include <ftxui/dom/node.hpp>      // for Render
+#include <ftxui/component/component.hpp>
+#include <ftxui/screen/screen.hpp>
+#include <ftxui/dom/canvas.hpp>
+#include <ftxui/screen/screen.hpp>
+#include <ftxui/dom/canvas.hpp>
+#include <ftxui/screen/screen.hpp>
+#include <ftxui/dom/canvas.hpp>
+#include <locale>
+#include <codecvt>
+
+using ftxui::Renderer, ftxui::Component, ftxui::Element, ftxui::Screen;
+
+struct Panel {
+  int x;
+  int y;
+  int width;
+  int height;
+  Component $component;
+  Screen $screen;
+  bool $must_clear = true;
+  std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>> $converter;
+
+  Panel(int width, int height, int x, int y, bool must_clear=true) :
+    x(x),
+    y(y),
+    width(width),
+    height(height),
+    $screen(width, height),
+    $must_clear(must_clear)
+  {};
+
+  void resize(int width, int height);
+  void set_renderer(std::function< Element()> render);
+  Screen &render();
+  std::wstring to_string();
+  Screen &screen();
+};