Add Graph.

examples/component/gallery.cpp

@@ -73,7 +73,7 @@ class MyComponent : public Component {
         separator(),
         Render(L"radiobox", radiobox),
         separator(),
-        Render(L"input", input) | size(WIDTH, EQUAL, 20)
+        Render(L"input", input) | size(WIDTH, LESS_THAN, 30)
       ) | border;
   }
 };

examples/dom/CMakeLists.txt

@@ -8,6 +8,7 @@ example(border)
 example(gauge)
 example(package_manager)
 example(separator)
+example(graph)
 example(spinner)
 example(style_blink)
 example(style_bold)

examples/dom/border.cpp

@@ -41,7 +41,7 @@ int main(int argc, const char *argv[])
       ),
       filler()
     );
-  auto screen = Screen::TerminalOutput(document);
+  auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
   Render(screen, document.get());
   std::cout << screen.ToString() << std::endl;
 }

examples/dom/dbox.cpp

@@ -16,7 +16,7 @@ int main(int argc, const char *argv[])
       ) | border,
       text(L"overlay") | border | center
     );
-  auto screen = Screen::TerminalOutput(document);
+  auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
   Render(screen, document.get());
 
   std::cout << screen.ToString();

examples/dom/graph.cpp

@@ -0,0 +1,65 @@
+#include "ftxui/dom/elements.hpp"
+#include "ftxui/dom/graph.hpp"
+#include "ftxui/screen/screen.hpp"
+#include "ftxui/screen/string.hpp"
+#include <chrono>
+#include <cmath>
+#include <iostream>
+#include <thread>
+
+class Graph : public ftxui::GraphFunction {
+ public:
+  std::vector<int> operator()(int width, int height) {
+    std::vector<int> output(width);
+    for (int i = 0; i < width; ++i) {
+      float v = 0;
+      v += 0.1 * sin((i + shift) * 0.1);
+      v += 0.2 * sin((i + shift+10) * 0.15);
+      v += 0.1 * sin((i + shift) * 0.03);
+      // v += 0.2*sin((i+shift)*0.3);
+      // v += 0.1*sin((i+shift)*0.9);
+      v *= height;
+      v += 0.5 * height;
+      output[i] = v;
+    }
+    return output;
+  }
+  int shift = 0;
+};
+
+int main(int argc, const char* argv[]) {
+  using namespace ftxui;
+  using namespace std::chrono_literals;
+
+  Graph my_graph;
+
+  std::string reset_position;
+  for (int i = 0;; ++i) {
+    auto document =
+      window(text(L"Your graphs"),
+        hbox(
+          vbox(
+            graph(my_graph), separator(),
+            graph(my_graph) | inverted
+          ) | flex,
+          separator(),
+          vbox(
+            graph(my_graph) | color(Color::BlueLight), separator(),
+            graph(my_graph) | color(Color::RedLight), separator(),
+            graph(my_graph) | color(Color::YellowLight)
+          ) | flex
+        )
+      ) | size(HEIGHT, GREATER_THAN, 40);
+
+    auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
+    Render(screen, document.get());
+    std::cout << reset_position << screen.ToString() << std::flush;
+
+    reset_position = screen.ResetPosition();
+
+    std::this_thread::sleep_for(0.03s);
+    my_graph.shift++;
+  }
+
+  return 0;
+}

examples/dom/hflow.cpp

@@ -43,7 +43,7 @@ int main(int argc, const char *argv[])
       | size(WIDTH, LESS_THAN, 50)
       ;
 
-  auto screen = Screen::TerminalOutput(document);
+  auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
   Render(screen, document.get());
   std::cout << screen.ToString() << std::endl;
 

examples/dom/html_like.cpp

@@ -39,7 +39,7 @@ int main(int argc, const char* argv[]) {
             paragraph(L" A spinner "), spinner(6, i / 10)) |
         border;
 
-    auto screen = Screen::TerminalFullscreen();
+    auto screen = Screen::Create(Dimension::Full());
     Render(screen, document.get());
     std::cout << reset_position << screen.ToString() << std::flush;
 

examples/dom/package_manager.cpp

@@ -115,7 +115,7 @@ int main(int argc, const char *argv[])
 
     // Draw.
     auto document = render();
-    auto screen = Screen::TerminalOutput(document);
+    auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
     Render(screen, document.get());
     std::cout << reset_position << screen.ToString() << std::flush;
     reset_position = screen.ResetPosition();

examples/dom/paragraph.cpp

@@ -24,7 +24,7 @@ int main(int argc, const char *argv[])
       ) | flex
     );
 
-  auto screen = Screen::TerminalFullscreen();
+  auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
   Render(screen, document.get());
   std::cout << screen.ToString();
   getchar();

examples/dom/separator.cpp

@@ -9,17 +9,18 @@ int main(int argc, const char *argv[])
     hbox(
       text(L"left-column"),
       separator(),
-      flex(vbox(
+      vbox(
-        center(text(L"right-column")) | flex,
+        center(text(L"right-top")) | flex,
         separator(),
-        center(text(L"bottom-column"))
+        center(text(L"bottom-bottom"))
-      ))
+      ) | flex,
-    );
+      separator(),
-  auto screen = Screen::TerminalFullscreen();
+      text(L"right-column")
+    ) | border;
+  auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
   Render(screen, document.get());
 
-  std::cout << screen.ToString();
+  std::cout << screen.ToString() << std::endl;
-  getchar();
 
   return 0;
 }

examples/dom/size.cpp

@@ -22,7 +22,7 @@ int main(int argc, const char *argv[])
     );
   }
   auto document = hbox(std::move(content));
-  auto screen = Screen::FitDocument(document);
+  auto screen = Screen::Create(Dimension::Fit(document));
   Render(screen, document.get());
   std::cout << screen.ToString() << std::endl;
 

examples/dom/spinner.cpp

@@ -26,7 +26,7 @@ int main(int argc, const char *argv[])
       );
     }
     auto document = hbox(vbox(std::move(entries)) | border, filler());
-    auto screen = Screen::TerminalOutput(document);
+    auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
     Render(screen, document.get());
     std::cout << reset_position << screen.ToString() << std::flush;
     reset_position = screen.ResetPosition();

examples/dom/style_blink.cpp

@@ -11,7 +11,7 @@ int main(int argc, const char *argv[])
       text(L"blink") | blink,
       text(L". Do you like it?")
     );
-  auto screen = Screen::TerminalOutput(document);
+  auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
   Render(screen, document.get());
 
   std::cout << screen.ToString();

examples/dom/style_bold.cpp

@@ -11,7 +11,7 @@ int main(int argc, const char *argv[])
       text(L"bold") | bold,
       text(L". Do you like it?")
     );
-  auto screen = Screen::TerminalOutput(document);
+  auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
   Render(screen, document.get());
 
   std::cout << screen.ToString();

examples/dom/style_color.cpp

@@ -48,7 +48,7 @@ int main(int argc, const char *argv[])
       filler()
     );
 
-  auto screen = Screen::TerminalOutput(document);
+  auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
   Render(screen, document.get());
 
   std::cout << screen.ToString();

examples/dom/style_dim.cpp

@@ -11,7 +11,7 @@ int main(int argc, const char *argv[])
       text(L"dim") | dim,
       text(L". Do you like it?")
     );
-  auto screen = Screen::TerminalOutput(document);
+  auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
   Render(screen, document.get());
 
   std::cout << screen.ToString();

examples/dom/style_gallery.cpp

@@ -16,7 +16,7 @@ int main(int argc, const char *argv[])
       text(L"color")     | color(Color::Blue)   , text(L" ") ,
       text(L"bgcolor")   | bgcolor(Color::Blue)
     );
-  auto screen = Screen::TerminalOutput(document);
+  auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
   Render(screen, document.get());
 
   std::cout << screen.ToString();

examples/dom/style_inverted.cpp

@@ -11,7 +11,7 @@ int main(int argc, const char *argv[])
       text(L"inverted") | inverted,
       text(L". Do you like it?")
     );
-  auto screen = Screen::TerminalOutput(document);
+  auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
   Render(screen, document.get());
 
   std::cout << screen.ToString();

examples/dom/style_underlined.cpp

@@ -11,7 +11,7 @@ int main(int argc, const char *argv[])
       text(L"underlined") | underlined,
       text(L". Do you like it?")
     );
-  auto screen = Screen::TerminalOutput(document);
+  auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
   Render(screen, document.get());
 
   std::cout << screen.ToString();

examples/dom/vbox_hbox.cpp

@@ -28,7 +28,7 @@ int main(int argc, const char *argv[])
         text(L"south-east")
       )
     );
-  auto screen = Screen::TerminalFullscreen();
+  auto screen = Screen::Create(Dimension::Full());
   Render(screen, document.get());
 
   std::cout << screen.ToString();

ftxui/CMakeLists.txt

@@ -18,6 +18,7 @@ add_library(dom
   src/ftxui/dom/flex.cpp
   src/ftxui/dom/frame.cpp
   src/ftxui/dom/gauge.cpp
+  src/ftxui/dom/graph.cpp
   src/ftxui/dom/hbox.cpp
   src/ftxui/dom/hflow.cpp
   src/ftxui/dom/inverted.cpp

ftxui/include/ftxui/component/checkbox.hpp

@@ -17,7 +17,7 @@ class CheckBox : public Component {
 
   //std::wstring checked = L"[X] ";
   //std::wstring unchecked = L"[ ] ";
-  std::wstring checked = L"☑ ";
+  std::wstring checked = L"▣ ";
   std::wstring unchecked = L"☐ ";
 
   Decorator focused_style = inverted;

ftxui/include/ftxui/component/screen_interactive.hpp

@@ -10,7 +10,7 @@ class Component;
 
 class ScreenInteractive : public Screen {
   public:
-    static ScreenInteractive FixedSize(size_t dimx, size_t dimy);
+    static ScreenInteractive FixedSize(int dimx, int dimy);
     static ScreenInteractive Fullscreen();
     static ScreenInteractive FitComponent();
     static ScreenInteractive TerminalOutput();
@@ -30,7 +30,7 @@ class ScreenInteractive : public Screen {
      TerminalOutput,
    };
    Dimension dimension_ = Dimension::Fixed;
-   ScreenInteractive(size_t dimx, size_t dimy, Dimension dimension);
+   ScreenInteractive(int dimx, int dimy, Dimension dimension);
 };
 
 }  // namespace ftxui

ftxui/include/ftxui/dom/elements.hpp

@@ -3,6 +3,7 @@
 
 #include <functional>
 
+#include "ftxui/dom/graph.hpp"
 #include "ftxui/dom/node.hpp"
 #include "ftxui/screen/color.hpp"
 
@@ -20,6 +21,7 @@ Element border(Element);
 Element window(Element title, Element content);
 Element spinner(int charset_index, size_t image_index);
 Elements paragraph(std::wstring text); // Use inside hflow(). Split by space.
+Element graph(GraphFunction&); // See graph.hpp
 
 // -- Decorator ---
 Element bold(Element);
@@ -68,6 +70,7 @@ Element nothing(Element element);
 // Pipe elements into decorator togethers.
 // Examples: text("ftxui") | bold | underlined;
 Element operator|(Element, Decorator);
+Elements operator|(Elements, Decorator);
 Decorator operator|(Decorator, Decorator);
 
 // Make container able to take any number of children as input.

ftxui/include/ftxui/dom/graph.hpp

@@ -0,0 +1,15 @@
+#ifndef FTXUI_DOM_GRAPH_HPP
+#define FTXUI_DOM_GRAPH_HPP
+
+#include "ftxui/dom/elements.hpp"
+
+namespace ftxui {
+
+class GraphFunction {
+ public:
+  virtual std::vector<int> operator()(int width, int height) = 0;
+};
+
+} // namespace ftxui
+
+#endif /* end of include guard: FTXUI_DOM_GRAPH_HPP */

ftxui/include/ftxui/screen/screen.hpp

@@ -25,26 +25,32 @@ struct Pixel {
   Color foreground_color = Color::Default;
 };
 
+struct Dimension {
+  static Dimension Fixed(int);
+  static Dimension Fit(std::unique_ptr<Node>&);
+  static Dimension Full();
+
+  int dimx;
+  int dimy;
+};
+
 class Screen {
  public:
   // Constructor.
-  Screen(size_t dimx, size_t dimy);
+  Screen(int dimx, int dimy);
-
+  static Screen Create(Dimension dimension);
-  // Constructor using the terminal.
+  static Screen Create(Dimension width, Dimension height);
-  static Screen TerminalFullscreen();
-  static Screen TerminalOutput(std::unique_ptr<Node>& element);
-  static Screen FitDocument(std::unique_ptr<Node>& element);
 
   // Node write into the screen using Screen::at.
-  wchar_t& at(size_t x, size_t y);
+  wchar_t& at(int x, int y);
-  Pixel& PixelAt(size_t x, size_t y);
+  Pixel& PixelAt(int x, int y);
 
   // Convert the screen into a printable string in the terminal.
   std::string ToString();
 
   // Get screen dimensions.
-  size_t dimx() { return dimx_;}
+  int dimx() { return dimx_;}
-  size_t dimy() { return dimy_;}
+  int dimy() { return dimy_;}
 
   // Move the terminal cursor n-lines up with n = dimy().
   std::string ResetPosition();
@@ -56,8 +62,8 @@ class Screen {
   Box stencil;
 
  protected:
-  size_t dimx_;
+  int dimx_;
-  size_t dimy_;
+  int dimy_;
   std::vector<std::vector<Pixel>> pixels_;
 };
 

ftxui/src/ftxui/component/screen_interactive.cpp

@@ -44,14 +44,14 @@ Event GetEvent() {
 
 };  // namespace
 
-ScreenInteractive::ScreenInteractive(size_t dimx,
+ScreenInteractive::ScreenInteractive(int dimx,
-                                     size_t dimy,
+                                     int dimy,
                                      Dimension dimension)
     : Screen(dimx, dimy), dimension_(dimension) {}
 ScreenInteractive::~ScreenInteractive() {}
 
 // static
-ScreenInteractive ScreenInteractive::FixedSize(size_t dimx, size_t dimy) {
+ScreenInteractive ScreenInteractive::FixedSize(int dimx, int dimy) {
   return ScreenInteractive(dimx, dimy, Dimension::Fixed);
 }
 
@@ -106,8 +106,8 @@ void ScreenInteractive::Loop(Component* component) {
 
 void ScreenInteractive::Draw(Component* component) {
   auto document = component->Render();
-  size_t dimx;
+  int dimx;
-  size_t dimy;
+  int dimy;
   switch (dimension_) {
     case Dimension::Fixed:
       dimx = dimx_;

ftxui/src/ftxui/dom/graph.cpp

@@ -0,0 +1,45 @@
+#include "ftxui/dom/elements.hpp"
+
+namespace ftxui {
+
+const wchar_t charset[] = L" ▗▐▖▄▟▌▙█";
+
+class Graph : public Node {
+ public:
+  Graph(GraphFunction& graph_function) : graph_function_(graph_function) {}
+  ~Graph() override {}
+
+  void ComputeRequirement() override {
+    requirement_.flex.x = 1;
+    requirement_.flex.y = 1;
+    requirement_.min.x = 1;
+    requirement_.min.y = 1;
+  }
+
+  void Render(Screen& screen) override {
+    int width = (box_.x_max - box_.x_min + 1) * 2;
+    int height = (box_.y_max - box_.y_min + 1) * 2;
+    auto data = graph_function_(width, height);
+    int i = 0;
+    for (int x = box_.x_min; x <= box_.x_max; ++x) {
+      int height_1 = 2 * box_.y_max - data[i++];
+      int height_2 = 2 * box_.y_max - data[i++];
+      for (int y = box_.y_min; y <= box_.y_max; ++y) {
+        int yy = 2 * y;
+        int i_1 = yy < height_1 ? 0 : yy == height_1 ? 3 : 6;
+        int i_2 = yy < height_2 ? 0 : yy == height_2 ? 1 : 2;
+        wchar_t pix = charset[i_1 + i_2];
+        screen.at(x, y) = pix;
+      }
+    }
+  }
+
+ private:
+  GraphFunction& graph_function_;
+};
+
+std::unique_ptr<Node> graph(GraphFunction& graph_function) {
+  return std::make_unique<Graph>(graph_function);
+}
+
+};  // namespace ftxui

ftxui/src/ftxui/dom/hflow.cpp

@@ -12,7 +12,7 @@ class HFlow : public Node {
     requirement_.min.x = 0;
     requirement_.min.y = 0;
     requirement_.flex.x = 1;
-    requirement_.flex.y = 0;
+    requirement_.flex.y = 1;
     for(auto& child : children)
       child->ComputeRequirement();
   }

ftxui/src/ftxui/dom/util.cpp

@@ -19,6 +19,13 @@ Decorator operator|(Decorator a, Decorator b) {
   return compose(a, b);
 }
 
+Elements operator|(Elements es, Decorator d) {
+  Elements output;
+  for (auto& it : es)
+    output.push_back(std::move(it) | d);
+  return output;
+}
+
 Element operator|(Element e, Decorator d) {
   return d(std::move(e));
 }

ftxui/src/ftxui/screen/screen.cpp

@@ -1,5 +1,5 @@
-#include "ftxui/dom/node.hpp"
 #include "ftxui/screen/screen.hpp"
+#include "ftxui/dom/node.hpp"
 #include "ftxui/screen/string.hpp"
 #include "ftxui/screen/terminal.hpp"
 
@@ -36,8 +36,34 @@ Pixel dev_null_pixel;
 
 } // namespace
 
-Screen::Screen(size_t dimx, size_t dimy)
+Dimension Dimension::Fixed(int v) {
-    : stencil({0, int(dimx) - 1, 0, int(dimy) - 1}),
+  return Dimension{v, v};
+}
+
+Dimension Dimension::Fit(std::unique_ptr<Node>& e) {
+  e->ComputeRequirement();
+  Terminal::Dimensions size = Terminal::Size();
+  return Dimension{std::min(e->requirement().min.x, size.dimx),
+                   std::min(e->requirement().min.y, size.dimy)};
+}
+
+Dimension Dimension::Full() {
+  Terminal::Dimensions size = Terminal::Size();
+  return Dimension{size.dimx, size.dimy};
+}
+
+// static
+Screen Screen::Create(Dimension width, Dimension height) {
+  return Screen(width.dimx, height.dimy);
+}
+
+// static
+Screen Screen::Create(Dimension dimension) {
+  return Screen(dimension.dimx, dimension.dimy);
+}
+
+Screen::Screen(int dimx, int dimy)
+    : stencil({0, dimx - 1, 0, dimy - 1}),
       dimx_(dimx),
       dimy_(dimy),
       pixels_(dimy, std::vector<Pixel>(dimx)) {}
@@ -72,10 +98,10 @@ std::string Screen::ToString() {
 
   Pixel previous_pixel;
 
-  for (size_t y = 0; y < dimy_; ++y) {
+  for (int y = 0; y < dimy_; ++y) {
     if (y != 0)
       ss << '\n';
-    for (size_t x = 0; x < dimx_; ++x) {
+    for (int x = 0; x < dimx_; ++x) {
       UpdatePixelStyle(ss, previous_pixel, pixels_[y][x]);
       ss << pixels_[y][x].character;
     }
@@ -88,42 +114,18 @@ std::string Screen::ToString() {
   return to_string(ss.str());
 }
 
-wchar_t& Screen::at(size_t x, size_t y) {
+wchar_t& Screen::at(int x, int y) {
   return PixelAt(x,y).character;
 }
 
-Pixel& Screen::PixelAt(size_t x, size_t y) {
+Pixel& Screen::PixelAt(int x, int y) {
   return In(stencil, x, y) ? pixels_[y][x] : dev_null_pixel;
 }
 
-// static
-Screen Screen::TerminalFullscreen() {
-  Terminal::Dimensions size = Terminal::Size();
-  return Screen(size.dimx, size.dimy);
-}
-
-// static
-Screen Screen::TerminalOutput(std::unique_ptr<Node>& element) {
-  element->ComputeRequirement();
-  Terminal::Dimensions size = Terminal::Size();
-  return Screen(size.dimx, element->requirement().min.y);
-}
-
-// static
-Screen Screen::FitDocument(std::unique_ptr<Node>& element) {
-  element->ComputeRequirement();
-  Terminal::Dimensions size = Terminal::Size();
-  return
-    Screen(
-      std::min(size.dimx, element->requirement().min.x),
-      std::min(size.dimy, element->requirement().min.y)
-    );
-}
-
 std::string Screen::ResetPosition() {
   std::stringstream ss;
   ss << MOVE_LEFT << CLEAR_LINE;
-  for (size_t y = 1; y < dimy_; ++y) {
+  for (int y = 1; y < dimy_; ++y) {
     ss << MOVE_UP << CLEAR_LINE;
   }
   return ss.str();
@@ -137,8 +139,8 @@ void Screen::Clear() {
 void Screen::ApplyShader() {
 
   // Merge box characters togethers.
-  for(size_t y = 1; y<dimy_; ++y) {
+  for(int y = 1; y<dimy_; ++y) {
-    for(size_t x = 1; x<dimx_; ++x) {
+    for(int x = 1; x<dimx_; ++x) {
       wchar_t& left = at(x - 1, y);
       wchar_t& top = at(x, y - 1);
       wchar_t& cur = at(x, y);