curve with straight lines

[Dr Unne]

#!/usr/bin/ruby
require 'gtk2'
require 'gnomecanvas2'

class CurveFromLines

    def initialize(size=150)
        Gtk.init()


        @window = Gtk::Window.new()
        @window.set_title("LinesFromCurve")
        @window.set_default_size(size*2,size*2)
        @window.signal_connect("delete_event") { Gtk::main_quit() }

        @canvas = Gnome::Canvas.new()

        @canvas.set_center_scroll_region(true)
        @canvas.set_pixels_per_unit(0.8)
        @root = @canvas.root

        0.upto(size) do |x|
            color = 65535 - (x * 65535 / size)
            line = Gnome::CanvasLine.new(
                @root,
                { 
                    :points => [[0,x], [size-x,0]],
                    :"fill-color-gdk" => Gdk::Color.new(color,color,color)
                }
            )
            line2 = Gnome::CanvasLine.new(
                @root,
                { 
                    :points => [[0,-x], [-size+x,0]],
                    :"fill-color-gdk" => Gdk::Color.new(color,color,color)
                }
            )
        end

        @vbox = Gtk::VBox.new()
        @vbox.pack_start(@canvas)

        @window.add(@vbox)
        @window.show_all()
        Gtk.main()
    end
end

curve = CurveFromLines.new(250)