add BufferWidget#initialize, #render, add a BufferWidget to Window

runtime/lib/buffer_widget.rb

@@ -1,5 +1,18 @@
 require "widget"
 
 class BufferWidget
+
   include Widget
+
+  def initialize(buffer, font)
+    @buffer = buffer
+    @font = font
+  end
+
+  def render
+    (0...@buffer.size).each do |i|
+      draw_text(@font, 0, @height - @font.line_height * (i + 1), @buffer[i], 1, 1, 1, 1)
+    end
+  end
+
 end

runtime/lib/window.rb

@@ -20,6 +20,8 @@ class Window
   def initialize
     Window.register(self)
     super
+    @font = Font.new(Runtime.find(:font, "DejaVuSansMono"), 20)
+    @buffer_widget = BufferWidget.new(Buffer.new, @font)
   end
 
   def close
@@ -27,6 +29,12 @@ class Window
   end
 
   def render
+    @buffer_widget.draw
+  end
+
+  def resize(x, y, width, height)
+    super
+    @buffer_widget.resize(x, y, width, height)
   end
 
 end