main.rb

require 'gosu'
require 'rtesseract'

FILE  = ARGV.join(' ').strip
IMAGE = Gosu::Image.new(FILE)
RED   = Gosu::Color.argb(0xff_ff0000)
GREEN = Gosu::Color.argb(0xff_00ff00)
BLUE  = Gosu::Color.argb(0xff_0000ff)

PADDING   = 4
THICKNESS = 3

Element = Struct.new(:x1, :y1, :x2, :y2) do
	def draw(color=RED)
		Gosu.draw_rect(x1-THICKNESS, y1-THICKNESS, x2-x1+(THICKNESS*2), THICKNESS,           color)
		Gosu.draw_rect(x1-THICKNESS, y1-THICKNESS, THICKNESS,           y2-y1+(THICKNESS*2), color)
		Gosu.draw_rect(x1-THICKNESS, y2,           x2-x1+(THICKNESS*2), THICKNESS,           color)
		Gosu.draw_rect(x2,           y1-THICKNESS, THICKNESS,           y2-y1+(THICKNESS*2), color)
	end

	def line_to(element)
		start_point = end_point = []
		distance = 0
		min = (IMAGE.width**2 + IMAGE.height**2)/2
		corners().each do |corner|
			element.corners().each do |target|
				dis = Math.sqrt(
					(corner[0] - target[0]).abs ** 2 +
					(corner[1] - target[1]).abs ** 2)

				if distance < min
					min         = distance
					start_point = corner
					end_point   = target
				end
			end
		end

		return [start_point[0], start_point[1], end_point[0], end_point[1]]
	end

	def corners
		[[x1,y1], [x2,y1], [x2,y2], [x1,y2]]
	end

	def under_mouse
		w.x1 < mouse_x and w.x2 > mouse_x and w.y1 < mouse_y and w.y2 > mouse_y
	end
end

WORDS = RTesseract.new(FILE).to_box.map { |box| Element.new(box[:x_start]-PADDING, box[:y_start]-PADDING, box[:x_end]+PADDING, box[:y_end]+PADDING) }

class Screenshot < Gosu::Window
	def initialize()
		super IMAGE.width, IMAGE.height
		self.caption = "Screenshot editor"

		reset()
	end

	def button_down(id)
		case id
		when Gosu::KbQ
			close

		when Gosu::MsLeft
			WORDS.each { |w| @group << w if under_mouse(w) }

			if not @group.empty?
				min_x1 = @group.map { |g| g.x1 }.min
				max_x2 = @group.map { |g| g.x2 }.max
				min_y1 = @group.map { |g| g.y1 }.min
				max_y2 = @group.map { |g| g.y2 }.max

				@gelem = Element.new(min_x1, min_y1, max_x2, max_y2)
			end

		when Gosu::KbReturn
			@unselected << @gelem unless @gelem.nil?
			@group = []
			@gelem = nil

		when Gosu::KbX
			@unselected.each { |c| @unselected.delete(c) if under_mouse(c) }

		when Gosu::KbS
			output = "#{FILE.split('.')[0..-2].join('.')}_highlighted.png"
			Gosu.render(IMAGE.width, IMAGE.height) do
				draw()
			end.save(output)
			puts output
			close

		when 46, 87 # plus
			@unselected.each do |c|
				if under_mouse(c)
					c.x1 -= 5
					c.x2 += 5
					c.y1 -= 5
					c.y2 += 5
				end
			end

		when 45, 86 # minus
			@unselected.each do |c|
				if under_mouse(c)
					c.x1 += 5
					c.x2 -= 5
					c.y1 += 5
					c.y2 -= 5
				end
			end

		when Gosu::KbO
			reset()

		when Gosu::KbC
			@unselected.each do |c|
				if under_mouse(c)
					@pair << c
					if @pair.length == 2
						@lines << @pair[0].line_to(@pair[1])
						@pair = []
					end
					break
				end
			end
			
		when Gosu::KbR
			e = Element.new(mouse_x, mouse_y, mouse_x+1, mouse_y+1)
			@group << e
			min_x1 = @group.map { |g| g.x1 }.min
			max_x2 = @group.map { |g| g.x2 }.max
			min_y1 = @group.map { |g| g.y1 }.min
			max_y2 = @group.map { |g| g.y2 }.max

			@gelem = Element.new(min_x1, min_y1, max_x2, max_y2)

		end
	end

	def reset
		@unselected = []
		@group      = []
		@pair       = []
		@lines      = []
		@gelem      = nil
	end

	def under_mouse(word)
		word.x1 < mouse_x and word.x2 > mouse_x and word.y1 < mouse_y and word.y2 > mouse_y
	end

	def draw
		IMAGE.draw(0,0)
		WORDS.each do |word|
			if under_mouse(word)
				word.draw()
				break
			end
		end

		@gelem.draw(GREEN) if not @gelem.nil?

		@unselected.each { |c| c.draw()     }
		@pair.each       { |p| p.draw(BLUE) }

		@lines.each do |l|
			Gosu.draw_quad(
				l[0]-1, l[1]-1, RED,
				l[0]+1, l[1]+1, RED,
				l[2]+1, l[3]+1, RED,
				l[2]-1, l[3]-1, RED
			)

			Gosu.draw_quad(
				l[0]-1, l[1]+1, RED,
				l[0]+1, l[1]-1, RED,
				l[2]+1, l[3]-1, RED,
				l[2]-1, l[3]+1, RED
			)
		end

	end
end

Screenshot.new().show