Exporting cf3ruby directly to 'large' pdf

With the processing pdf export library it is easy to export processing sketches to pdf. This is also true for ruby-processing sketches, including those using the cf3ruby library see example below:-

# levy.rb ruby-processing NB: :alpha is now implemented ruby-processing
require 'cf3', 'pdf'
include_package 'processing.pdf'

def setup_the_levy
  @levy = ContextFree.define do
    shape :start do
      levy brightness: 0.9
    end
    shape :levy do
      square alpha: 0.1
     split do
        levy  size: 1/Math.sqrt(2), rotation: -45, x: 0.5, brightness: 0.9
        rewind
        levy  size: 1/Math.sqrt(2), rotation: 45, x: 0.5, brightness: 0.9
     end
    end
  end
end


def setup
  size 2000, 2000, PDF, "levy.pdf"
  setup_the_levy
  smooth
  draw_it
end


def draw
  exit
end


def draw_it
  background 255
  @levy.render :start, size: 250,  stop_size: 2,
        start_x: width/4, start_y: height/2
end

Context Free Tree in cf3ruby

#################################################################
# A non deterministic sketch run it until you get a result you like
# uncomment "srand 5" to get a more deterministic result. It looked
# pretty good on my linux box (however I'm not sure how universal the 
# random seeding is in jruby)
#################################################################

require 'cf3'

def setup_the_tree
  @tree = ContextFree.define do
    shape :trunk, 20 do                         # rule has a probability weighting of 20
      circle size: 0.25, brightness: 0.5     # giving an actual probability = 0.952381
      scraggle y: -0.1                      # the minus is require by the upside down coordinate system             
    end

    shape :trunk, 1 do                      # rule has a probability weighting of 1
      branch size: 0.7                      # giving an actual probability = 0.047619  
    end

    shape :trunk, 0.02 do                    # empty rule top stop early    
    end

    shape :branch do
      split do                               # split is like a branch, rewind returns original context
        trunk rotation: 10
      rewind
        trunk rotation: -10
      end
    end

    shape :scraggle do                       # without an explicit weighting    
      trunk rotation: 5                      # probability of each scraggle rule 
    end                                      # is 0.5

    shape :scraggle do
      trunk rotation: -5
    end
  end
end

def setup
  size 600, 600
  srand 5
  smooth
  setup_the_tree
  background 255         # NB color mode here is "RGB 255", within context free definition 
  draw_it                # the color mode is "HSB 1.0", supports :hue, :saturation, :brightness
  save_frame "/home/tux/tree4.png"
end

def draw_it
  @tree.render :trunk, start_x: width/2, start_y: height * 0.9, stop_size: height/150, size: height/15
end

New context_free.rb (cf3ruby)

Here is my "y" window sketch using my modified ruby-processing library (features CF3 syntax, ie shape replaces rule, also ruby 1.9 hash syntax).

# y.rb ruby-processing
require 'cf3'
Y_TOP = -1 / Math.sqrt(3)
Y_BOT = Math.sqrt(3) / 6

def setup_the_triangle
  @triangle = ContextFree.define do
    ########  
    shape :start do
    unit brightness: 1.0
    end

    shape :unit do
      triangle size: 1.0
      split do
        unit size: 0.5, x: 0, y: Y_TOP/2, brightness: 0.8
        rewind
        unit size: 0.5, x: -0.25, y: -Y_TOP/4, brightness: 0.8
        rewind
        unit size: 0.5, x: 0.25, y: -Y_TOP/4, brightness: 0.8
      end
    end
    ########
  end
end

def setup
  size 1024, 1024
  setup_the_triangle
  no_stroke
  color_mode RGB, 1
  smooth
  draw_it
  save_frame("y.png")
end


def draw
   # Do nothing.
end

def draw_it
  background 225, 225, 0
  @triangle.render :start, size: height, stop_size: 0.5,
  start_x: width/2, start_y: height * 0.6
end

Fix for ruby-processing context free

The adoption of jruby-1.7.0 for the latest version of processing has required changes to the context_free.rb script. See the change on my Pembrokeshire Branch. My dragon sketch and city sketches working fine, I haven't checked any other. Here is my dragon sketch updated to ruby-1.9 syntax (NB: continues work with 1.8 syntax)

# contributed by monkstone

load_library 'context_free'

def setup_the_dragon
  @dragon = ContextFree.define do

    rule :start do
      dragon alpha: 1
    end

    rule :dragon do
      square hue: 0, brightness: 0, saturation: 1, alpha: 0.02
      split do
        dragon size: 1/Math.sqrt(2), rotation: -45, x: 0.25, y: 0.25
        rewind
        dragon size: 1/Math.sqrt(2), rotation: 135, x: 0.25, y: 0.25
        rewind
      end
    end

  end
end

def setup
  size 800, 500
  setup_the_dragon
  smooth
  draw_it
end

def draw
  # Do nothing.
end

def draw_it
  background 255
  @dragon.render :start, size: width*0.8,  stop_size: 2,
                         start_x: width/3, start_y: height/3.5
end

Here's a sketch with a simple custom shape of an isosceles triangle

load_library 'context_free'

def setup_the_spiral
  @spiral= ContextFree.define do
    ############ Begin defining custom terminal, an isoceles triangle     
    class << self
      define_method(:isoceles) do |some_options| # isoceles triangle
        size, options = *self.get_shape_values(some_options)
        rot = options[:rotation]
        rotate(rot) if rot
        $app.triangle(-0.5 * size, -0.5 * size, -0.5 * size, 0.5 * size, 0.5 * size, 0.5 * size)
        rotate(-rot) if rot
      end
    end
    ########### End definition of custom terminal 'isoceles'
    rule :spiral do
      isoceles brightness: -1, rotation: 90
      spiral rotation: 135, size: 1/sqrt(2), x: 1/sqrt(2)
    end
  end
end

def setup
  size 800, 500
  setup_the_spiral
  draw_it
end

def draw
  # Do nothing.
end

def draw_it
  background 255
  @spiral.render :spiral, size: height, start_x: width/3, start_y: height/2
end

A Staffordshire Knot Using Ruby Processing and A Context Free Library

A Staffordshire Knot, ruby-processing 3D context-free DSL from monkstone on Vimeo.

Using a slight variation of the previous post we get something similar to the Staffordshire Knot.


segment :rz => i, :ry => Math.sin(i*Math::PI/180)*0.2, :x => Math.sin(i*Math::PI/180)*1.5


Is the main change, although to produce the video, I was saving frames and set the size to 640*480 to match vimeo preferences. Was very jumpy when I saved frames as #####.png ...

I have since uploaded an improved version, this time using the default save_frame (hence tif format). Mencoder doesn't like this format so I batch converted the tif files to png as so:-

mogrify -format png -transparent blue *.tif


See my processing blog for the video recording details.

3D Context Free DSL Screen Saver?

Here is an animated version of the default.es from StructureSynth in ruby-processing. Mac or windows users might want to experiment with OPENGL rendering, as this sketch exposes errors in processing P3D, I see odd missing pixels from time to time. If you don't like the holes remove the smooth, personally I prefer the holes to the glitchty non-smooth (it is a known issue with current versions of processing with both P2D and P3D renderers, something to do with tessellation algorithms).  The test_free library is as in previous post.
Nest the library as follows:-
library/test_free/test_free.rb in the folder containing the sketch
For instructions for installing ruby-processing follow the first link in the blog header.


# full_screen.rb
# An animation of default.es
# the StructureSynth default script

load_libraries :test_free
full_screen
attr_reader :xrot, :yrot, :zrot

def setup_the_spiral
  @spiral = ContextFree.define do

    rule :default do
      split do
      R1 :brightness => 1
      rewind
      R2 :brightness => 1
    end
    end

    rule :R1 do                      
      sphere :brightness => 1
      R1 :size => 0.99, :x => 0.25, :rz => 6, :ry => 6
    end

    rule :R2 do                      
      sphere :brightness => 1
      R2 :size => 0.99, :x => -0.25, :rz => 6, :ry => 6
    end

  end
end

def setup
  render_mode P3D
  smooth
  @xrot = 0.01
  @yrot = 0
  @zrot = 0
  setup_the_spiral
end

def draw
  background 0
  lights
  smooth_rotation(6.7, 7.3)
  @spiral.render :default, :start_x => 0, :start_y => 0, :start_z => -50, :size => height/350,
  :stop_size => 0.2, :color => [0, 0.8, 0.8], :rx => xrot, :ry => yrot, :rz => zrot
end

##
# Generate a vector whose components change smoothly over time in the range [ 0, 1 ].
# Each component uses a Math.sin() function to map the current time in milliseconds somewhere
# in the range [ 0, 1 ].A 'speed' factor is specified for each component.
#
def smooth_vector(s1, s2)
  mills = millis * 0.00003
  y = 0.5 * Math.sin(mills * s1) + 0.5
  z = 0.5 * Math.sin(mills * s2) + 0.5
  vec = [y, z]
end

##
# Rotate the current coordinate system.
# Uses smooth_vector() to smoothly animate the rotation.
#
def smooth_rotation(s1, s2)
  r1 = smooth_vector(s1, s2)
  @yrot = (2.0 * Math::PI * r1[0])
  @zrot = (2.0 * Math::PI * r1[1])
end