Split up lenny use to_curve_vertex

Author: monkstone

contributed/lenny_explorer.rb

@@ -1,8 +1,8 @@
-# lenny_explorer.rb
+# A simple lenny explorer (see Vec2D library folder for more examples)
 # After 'The Explorer' by Leander Herzog, and a toxiclibs version by Karsten
 # Schmidt. This is a pure JRubyArt version by Martin Prout
 load_library :lenny
-attr_reader :path
+attr_reader :path, :renderer
 
 def settings
   size(600, 600)
@@ -11,29 +11,19 @@ def settings
 def setup
   sketch_title 'Lenny Explorer'
   no_fill
-  # @path = Path.new(
-  #   Boundary.new(
-  #     Rect.new(
-  #       Vec2D.new(10, 10),
-  #       Vec2D.new(width - 20, height - 20)
-  #     )
-  #   ),
-  #   10,
-  #   0.03,
-  #   3_000
-  # )
   @path = Path.new(
     Boundary.new(Circle.new(Vec2D.new(width / 2, height / 2), 250)),
     10,
     0.03,
-    3_000
+    5_000
   )
+  @renderer = GfxRender.new(g)
 end
 
 def draw
   background(255)
   50.times { path.grow }
-  path.render(g)
+  path.render(g, renderer)
 end
 
 def mouse_pressed

contributed/library/lenny/lenny.rb

@@ -1,4 +1,3 @@
-require_relative 'lib/rect'
 require_relative 'lib/circle'
 require_relative 'lib/boundary'
 require_relative 'lib/path'

contributed/library/lenny/lib/path.rb

@@ -35,9 +35,9 @@ def search
     @searches += 1
   end
 
-  def render(gfx)
+  def render(gfx, renderer)
     gfx.begin_shape
-    path.map { |vec| gfx.curve_vertex(vec.x, vec.y) }
+    path.map { |vec| vec.to_curve_vertex(renderer) }
     gfx.end_shape
   end
 

processing_app/library/vecmath/vec2d/lenny_explorer.rb

@@ -0,0 +1,42 @@
+# A simple lenny explorer (see Vec2D library folder for more examples)
+# After 'The Explorer' by Leander Herzog, and a toxiclibs version by Karsten
+# Schmidt. This is a pure JRubyArt version by Martin Prout
+load_library :lenny
+attr_reader :path, :renderer
+
+def settings
+  size(600, 600)
+end
+
+def setup
+  sketch_title 'Lenny Explorer'
+  no_fill
+  # @path = Path.new(
+  #   Boundary.new(Circle.new(Vec2D.new(width / 2, height / 2), 250)),
+  #   10,
+  #   0.03,
+  #   5_000
+  # )
+  @path = Path.new(
+    Boundary.new(
+      Rect.new(
+        Vec2D.new(10, 10),
+        Vec2D.new(width - 20, height - 20)
+      )
+    ),
+    10,
+    0.03,
+    5_000
+  )
+  @renderer = GfxRender.new(g)
+end
+
+def draw
+  background(255)
+  50.times { path.grow }
+  path.render(g, renderer)
+end
+
+def mouse_pressed
+  save_frame data_path('lenny.png')
+end

processing_app/library/vecmath/vec2d/library/lenny/lenny.rb

@@ -0,0 +1,5 @@
+require_relative 'lib/rect'
+require_relative 'lib/circle'
+require_relative 'lib/boundary'
+require_relative 'lib/path'
+require_relative 'lib/line2d'

processing_app/library/vecmath/vec2d/library/lenny/lib/boundary.rb

@@ -0,0 +1,15 @@
+# Duck typing Boundary
+class Boundary
+  attr_reader :bounds
+  def initialize(bounds)
+    @bounds = bounds
+  end
+
+  def contains?(vec)
+    bounds.contains?(vec)
+  end
+
+  def centroid
+    bounds.centroid
+  end
+end

processing_app/library/vecmath/vec2d/library/lenny/lib/circle.rb

@@ -0,0 +1,12 @@
+# For use with Boundary
+class Circle
+  attr_reader :centroid, :radius
+  def initialize(center, radius)
+    @centroid = center
+    @radius = radius
+  end
+
+  def contains?(vec)
+    centroid.dist(vec) < radius
+  end
+end

processing_app/library/vecmath/vec2d/library/lenny/lib/line2d.rb

@@ -0,0 +1,19 @@
+# Use to detect whether instances of line intersect
+class Line2D
+  attr_reader :a, :b
+  def initialize(a, b)
+    @a = a
+    @b = b
+  end
+
+  def intersecting?(line)
+    denom = (line.b.y - line.a.y) * (b.x - a.x) - (line.b.x - line.a.x) * (b.y - a.y)
+    na = (line.b.x - line.a.x) * (a.y - line.a.y) - (line.b.y - line.a.y) * (a.x - line.a.x)
+    nb = (b.x - a.x) * (a.y - line.a.y) - (b.y - a.y) * (a.x - line.a.x)
+    return false if denom.zero?
+
+    ua = na / denom
+    ub = nb / denom
+    (ua >= 0.0 && ua <= 1.0 && ub >= 0.0 && ub <= 1.0)
+  end
+end

processing_app/library/vecmath/vec2d/library/lenny/lib/path.rb

@@ -0,0 +1,56 @@
+# Stores and manipulates the path
+class Path
+  attr_reader :path, :last, :bounds, :cut, :theta, :delta, :speed, :searches
+
+  def initialize(bounds, speed, delta, history)
+    @bounds = bounds
+    @speed = speed
+    @delta = delta
+    @theta = 0
+    @path = (0..history).map { bounds.centroid.copy }
+    @searches = 0
+    @last = Vec2D.new(path.first)
+  end
+
+  def grow
+    @delta = rand(-0.2..0.2) if rand < 0.1
+    if !intersecting?
+      move
+    else
+      search
+    end
+  end
+
+  def move
+    @last = path.first
+    path.pop
+    @theta += delta
+    path.unshift last + Vec2D.new(speed * Math.cos(theta), speed * Math.sin(theta))
+    @searches = 0
+  end
+
+  def search
+    @theta += delta
+    path[0] = last + Vec2D.new(speed * Math.cos(theta), speed * Math.sin(theta))
+    @searches += 1
+  end
+
+  def render(gfx, renderer)
+    gfx.begin_shape
+    path.map { |vec| vec.to_curve_vertex(renderer) }
+    gfx.end_shape
+  end
+
+  def intersecting?
+    return true unless bounds.contains?(path.first)
+
+    if searches < 100
+      a = Line2D.new(path[0], path[1])
+      (3...path.length).each do |i|
+        b = Line2D.new(path[i], path[i - 1])
+        return true if a.intersecting?(b)
+      end
+    end
+    false
+  end
+end