Revisiting My Voronoi Application

I had the idea for sometime to optimize this application. As before the application uses Lee Byrons library which in turn depends on John Lloyds QuickHull3D library (both can be accessed at the Lee Byron link). One day I might re-write the application to use a 3D mesh library directly. The major optimization here is to use processings built in pixels array functionality. The app will work best if the aspect ratio of the image is the same as the frame size (1:1 is probably optimal?). I have introduced an auto-scale feature that seems to work...

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	load_libraries :mesh, :control_panel
	import 'megamu.mesh.Voronoi'
	attr_reader :voronoi, :img, :pixels, :ready, :upper, :show, :points, :xr, :yr, :lower, :lowskip, :highskip
	def setup
	size 500, 500
	frame_rate 10
	file = select_input "Choose Image File"
	@img = load_image file
	(img.height/height <= img.width/width)? @img.resize(0, height) : @img.resize(width, 0)
	@xr = img.width
	@yr = img.height
	@img.load_pixels
	@img.update_pixels
	@ready = false
	@show = false
	setup_control
	@points = Array.new
	puts "done setup"
	end
	def setup_control
	control_panel do |c|
	c.title = "Control Panel"
	c.slider :upper, 0..255, 200
	c.slider :lower, 0..255, 150
	c.slider :lowskip, 1..20, 1
	c.slider :highskip, 1..20, 7
	# c.button :choose_image
	c.button :show_voronoi
	c.button :view_image
	c.button :save_voronoi
	end
	end
	def show_voronoi
	no_loop
	@ready = false
	@points.clear
	get_all_points if img
	@voronoi = Voronoi.new(@points.to_java(Java::float[]))
	@ready = true
	loop
	end
	def calculate_voronoi
	regions = voronoi.get_regions
	stroke(128)
	fill(0)
	regions.each do |region|
	region_coordinates = region.get_coords
	region.draw(self)
	end
	edges = voronoi.get_edges
	edges.each do |edge|
	start_x = edge[0]
	start_y = edge[1]
	end_x = edge[2]
	end_y = edge[3]
	line(start_x, start_y, end_x, end_y)
	end
	fill 128
	no_stroke
	end
	def draw
	background(0)
	stroke(128)
	if (ready)
	calculate_voronoi
	end
	if (show && img)
	tint(255, 100)
	image(img, 0, 0)
	end
	end
	# def choose_image
	# file = select_input("Choose Image File")
	# @img = load_image(file)
	# end
	def mouse_pressed
	no_loop
	b = brightness(img.pixels[(mouse_y-1) * xr + mouse_x-1]) if img
	puts "Brightness = #{b}"
	loop
	end
	def save_voronoi
	no_loop
	save_frame
	puts "finished!"
	loop
	end
	def view_image
	cursor CROSS
	@show = !show
	end
	def get_all_points
	x_array = []
	y_array = []
	x = 0
	y = 0
	while(x < (xr - highskip))
	x_array << x
	x += (rand * highskip + lowskip).round
	end
	while(y < (yr - highskip))
	y_array << y
	y += (rand * highskip + lowskip).round
	end
	x_array.each do |pos_x|
	y_array.each do |pos_y|
	b = brightness(img.pixels[(pos_y)*xr+pos_x])
	if (b <= upper && b >= lower)
	@points << [pos_x, pos_y]
	end
	end
	end
	puts "total #{points.size}"
	end

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