modified: samples/processing_app/basics/data/characters_strings.rb

	modified:   samples/processing_app/basics/data/datatype_conversion.rb
	modified:   samples/processing_app/basics/data/integers_floats.rb
	modified:   samples/processing_app/basics/data/true_false.rb

Author: monkstone

samples/processing_app/basics/data/characters_strings.rb

@@ -1,50 +1,30 @@
-#
-# Characters Strings. 
-#  
-# The character datatype, abbreviated as char, stores letters and 
-# symbols in the Unicode format, a coding system developed to support 
-# a variety of world languages. Characters are distinguished from other
-# symbols by putting them between single quotes ('P').<br />
-# <br />
-# A string is a sequence of characters. A string is noted by surrounding 
-# a group of letters with double quotes ("Processing"). 
-# Chars and strings are most often used with the keyboard methods, 
-# to display text to the screen, and to load images or files.<br />
-# <br />
-# The String datatype must be capitalized because it is a complex datatype.
-# A String is actually a class with its own methods, some of which are
-# featured below. 
-#
-
-attr_reader :letter, :words
+attr_reader :letter, :words, :fkey, :fstring
 
 def setup
   size 640, 360
-  @words = "Begin..."
+  @words = 'Begin...'
   # Create the font
-  text_font create_font("Georgia", 36)
+  text_font create_font('Georgia', 36)
+  @fkey = 'Current key: %s'
+  @fstring = 'The String is %s characters long'
 end
 
 def draw
   background(0) # Set background to black
-
   # Draw the letter to the center of the screen
   text_size(14)
-  text("Click on the program, then type to add to the String", 50, 50)
-  text("Current key: #{letter}", 50, 70)
-  text("The String is #{words.length()} characters long", 50, 90)
-  
+  text('Click on the program, then type to add to the String', 50, 50)
+  text(format(fkey, letter), 50, 70)
+  text(format(fstring, words.length), 50, 90)
   text_size(36)
   text(words, 50, 120, 540, 300)
 end
 
 def key_pressed
-  # The variable "key" always contains the value 
+  # The variable 'key' always contains the value
   # of the most recent key pressed.
-  if (('A'..'z').include?(key) || key == ' ')
-    @letter = key
-    @words = words + key
-    puts(key)
-  end
+  return unless ('A'..'z').include?(key) || key == ' '
+  @letter = key
+  @words = words + key
+  puts(key)
 end
-

samples/processing_app/basics/data/datatype_conversion.rb

@@ -6,36 +6,23 @@
 # "to_f" (to Float, which would be "double" in Processing, not "float")
 # "to_a" (to Array, i.e. from a Range or Hash)
 
-
 def setup
   size 200, 200
   # Ruby has no primitive datatypes, everything is an object!
-  # See:
+  fstring = "%s \t... is a %s object\n"
   [1, 2.0, 'a', "B", nil, false].each do |element|
-    puts
-    puts "#{element.inspect} ... is a #{element.class.name} object"
+    puts format(fstring, element.inspect.to_s, element.class.name)
   end
-  
   c = 'A' # String (!) as there is no char datatype in Ruby.
   # Single quotes are parsed without substitutions (i.e. "It is #{Time.now}.")
-  
-  f = c.ord.to_f # Sets f = 65.0
-  # was "[c].to_f" in Ruby 1.8
-  
+  f = c.ord.to_f     # Sets f = 65.0
   i = (f * 1.4).to_i # Sets i to 91
-  
-  b = (c.ord.to_i / 2) # Integer or FixNum as there is no byte in Ruby
-  
+  b = (c.ord / 2)    # Integer or FixNum as there is no equivalent byte in Ruby
   background 51
   no_stroke
-  
   rect f, 0, 40, 66
-  
   fill 204
   rect i, 67, 40, 66
-  
   fill 255
   rect b, 134, 40, 66
 end
-
-

samples/processing_app/basics/data/integers_floats.rb

@@ -1,28 +1,23 @@
-# Integers and floats are two different kinds of numerical data. 
-# An integer (more commonly called an int) is a number without 
-# a decimal point. A float is a floating-point number, which means 
-# it is a number that has a decimal place. Floats are used when
-# more precision is needed. 
-
+# ruby integers are objects of class Fixnum or Bignum. The Fixnum and Bignum
+# classes represent integers of differing sizes. Both classes descend from
+# Integer (and therefore Numeric). The floating-point numbers are objects of
+# class Float. Floats are used when more precision is needed. In java int and
+# float are primitives, so you can't send them messages unlike ruby.
 
 def setup
-  size 200, 200  
+  size 200, 200
   stroke 255
   frame_rate 30
-  
   @a = 0		# Create an instance variable "a" of class Integer
   @b = 0.0	# Create an instance variable "b" of class Float (because of "0.0")
 end
 
 def draw
   background 51
-  
   @a += 1
   @b += 0.2
-  
-  line @a, 0,        @a, height/2
-  line @b, height/2, @b, height
-  
+  line @a, 0, @a, height / 2
+  line @b, height / 2, @b, height
   @a = 0 if @a > width
   @b = 0 if @b > width
 end

samples/processing_app/basics/data/true_false.rb

@@ -1,5 +1,5 @@
-# Boolean data is one bit of information. True or false. 
-# It is common to use Booleans with control statements to 
+# Boolean data is one bit of information. True or false.
+# It is common to use Booleans with control statements to
 # determine the flow of a program. In this example, when the
 # boolean value "x" is true, vertical black lines are drawn and when
 # the boolean value "x" is false, horizontal gray lines are drawn.
@@ -8,24 +8,19 @@
 # that will fail an "if" test. Absolutely everything else passes "if".
 
 def setup
-  size 200, 200
+  size(640, 360)
   background 0
   stroke 0
-  
-  (1..width).step(2) do |i|
-    
-    x = i < (width/2) # Evaluates to true or false, depending on i
-    
+  middle = width / 2
+  d = 20
+  (d..width).step(d) do |i|
+    x = i < middle   # Evaluates to true or false, depending on i
     if x
       stroke 255
-      line i, 1, i, height-1
+      line i, 1, i, height - 1
     end
-    
-    if !x
-      stroke 126
-      line width/2, i, width-2, i
-    end
-    
+    next if x        # favour guard clause in ruby to a wrapped loop
+    stroke 126
+    line middle, i - middle + d, width - d, i - middle + d
   end
 end
-