JezK
Edit File: easter-egg.rb
require "reline" module IRB class << self class Vec def initialize(x, y, z) @x, @y, @z = x, y, z end attr_reader :x, :y, :z def sub(other) Vec.new(@x - other.x, @y - other.y, @z - other.z) end def dot(other) @x*other.x + @y*other.y + @z*other.z end def cross(other) ox, oy, oz = other.x, other.y, other.z Vec.new(@y*oz-@z*oy, @z*ox-@x*oz, @x*oy-@y*ox) end def normalize r = Math.sqrt(self.dot(self)) Vec.new(@x / r, @y / r, @z / r) end end class Canvas def initialize((h, w)) @data = (0..h-2).map { [0] * w } @scale = [w / 2.0, h-2].min @center = Complex(w / 2, h-2) end def line((x1, y1), (x2, y2)) p1 = Complex(x1, y1) / 2 * @scale + @center p2 = Complex(x2, y2) / 2 * @scale + @center line0(p1, p2) end private def line0(p1, p2) mid = (p1 + p2) / 2 if (p1 - p2).abs < 1 x, y = mid.rect @data[y / 2][x] |= (y % 2 > 1 ? 2 : 1) else line0(p1, mid) line0(p2, mid) end end def draw @data.each {|row| row.fill(0) } yield @data.map {|row| row.map {|n| " ',;"[n] }.join }.join("\n") end end class RubyModel def initialize @faces = init_ruby_model end def init_ruby_model cap_vertices = (0..5).map {|i| Vec.new(*Complex.polar(1, i * Math::PI / 3).rect, 1) } middle_vertices = (0..5).map {|i| Vec.new(*Complex.polar(2, (i + 0.5) * Math::PI / 3).rect, 0) } bottom_vertex = Vec.new(0, 0, -2) faces = [cap_vertices] 6.times do |j| i = j-1 faces << [cap_vertices[i], middle_vertices[i], cap_vertices[j]] faces << [cap_vertices[j], middle_vertices[i], middle_vertices[j]] faces << [middle_vertices[i], bottom_vertex, middle_vertices[j]] end faces end def render_frame(i) angle = i / 10.0 dir = Vec.new(*Complex.polar(1, angle).rect, Math.sin(angle)).normalize dir2 = Vec.new(*Complex.polar(1, angle - Math::PI/2).rect, 0) up = dir.cross(dir2) nm = dir.cross(up) @faces.each do |vertices| v0, v1, v2, = vertices if v1.sub(v0).cross(v2.sub(v0)).dot(dir) > 0 points = vertices.map {|p| [nm.dot(p), up.dot(p)] } (points + [points[0]]).each_cons(2) do |p1, p2| yield p1, p2 end end end end end private def easter_egg(type = nil) type ||= [:logo, :dancing].sample case type when :logo File.open(File.join(__dir__, 'ruby_logo.aa')) do |f| require "rdoc" RDoc::RI::Driver.new.page do |io| IO.copy_stream(f, io) end end when :dancing begin canvas = Canvas.new(Reline.get_screen_size) Reline::IOGate.set_winch_handler do canvas = Canvas.new(Reline.get_screen_size) end ruby_model = RubyModel.new print "\e[?1049h" 0.step do |i| # TODO (0..).each needs Ruby 2.6 or later buff = canvas.draw do ruby_model.render_frame(i) do |p1, p2| canvas.line(p1, p2) end end buff[0, 20] = "\e[0mPress Ctrl+C to stop\e[31m\e[1m" print "\e[H" + buff sleep 0.05 end rescue Interrupt ensure print "\e[0m\e[?1049l" end end end end end IRB.__send__(:easter_egg, ARGV[0]&.to_sym) if $0 == __FILE__