Purogo MyFirstTower

In Purogo/MyFirst3DDrawing we noticed that our cube's bottom and top had very similiar logic. Let's refactor this a little bit:

turtle("tower") do |*args|
  dimension = (args[0] || 5).to_i
  stories = (args[1] || 3).to_i
  block_type = (args[1] || :stone).to_sym

  # Draw base of cube
  square do
    4.times do |i|
      mark i
      forward dimension
      turnleft 90
    end
  end

  pillars do
    4.times do |i|
      goto i 
      turnup 90
      forward dimension
    end # Still at top of last pillar
    turndown 90
  end

  stories.times do
    square 
    pillars
  end
  square
end

This looks much different than cube but this is only because we wrapped the logic for our square into a named block called square and the logic for our pillars into pillars (See Purogo/MakingNamedBlocks to reacquiant yourself with named blocks).

The main algorithm now for building a tower is becoming pretty concise:

  stories.times do
    square 
    pillars
  end
  square

For each story we draw a square and then pillars from that square. So long as we are building new stories the sqare of the next floor will be the top of the previous floor. Except for the very top-most floor of the tower. So we add one extra square to cap off the tower.