Георги обнови решението на 21.12.2013 13:19 (преди почти 11 години)
+module Graphics
+ module Renderers
+ class Ascii
+ class << self
+ attr_accessor :foreword, :afterword, :visible, :invisible, :line_break
+ end
+
+ @foreword = ''
+ @afterword = ''
+ @visible = '@'
+ @invisible = '-'
+ @line_break = "\n"
+ end
+
+ class Html
+ class << self
+ attr_accessor :foreword, :afterword, :visible, :invisible, :line_break
+ end
+
+ @foreword = '<!DOCTYPE html>
+ <html>
+ <head>
+ <title>Rendered Canvas</title>
+ <style type="text/css">
+ .canvas {
+ font-size: 1px;
+ line-height: 1px;
+ }
+ .canvas * {
+ display: inline-block;
+ width: 10px;
+ height: 10px;
+ border-radius: 5px;
+ }
+ .canvas i {
+ background-color: #eee;
+ }
+ .canvas b {
+ background-color: #333;
+ }
+ </style>
+ </head>
+ <body>
+ <div class="canvas">'
+ @visible = '<b></b>'
+ @invisible = '<i></i>'
+ @line_break = '<br>'
+ @afterword = ' </div>
+ </body>
+ </html>'
+ end
+ end
+
+ class Point
+ attr_reader :x, :y
+
+ def initialize(x, y)
+ @x = x
+ @y = y
+ end
+
+ def each
+ yield self
+ end
+
+ def to_s
+ "Point(#{@x}, #{@y})"
+ end
+
+ def hash
+ to_s.hash
+ end
+
+ def ==(other)
+ @x == other.x and @y == other.y
+ end
+
+ alias_method :eql?, :==
+ end
+
+ class Line
+ attr_reader :from, :to
+
+ def initialize(from, to)
+ @from = from
+ @to = to
+
+ if @from.x > @to.x or @from.x == @to.x and @from.y > @to.y
+ @from, @to = @to, @from
+ end
+ end
+
+ def each
+ rasterize.each { |point| yield point }
+ end
+
+ def to_s
+ "Line(#{@from}, #{@to})"
+ end
+
+ def hash
+ to_s.hash
+ end
+
+ def ==(other)
+ @from == other.from and @to == other.to
+ end
+
+ alias_method :eql?, :==
+
+ def rasterize
+ d_x = (@from.x - @to.x).abs
+ d_y = (@from.y - @to.y).abs
+
+ if d_x < d_y
+ d = 2*d_x - d_y
+ else
+ d = 2*d_y - d_x
+ end
+
+ bresenham(@from.x, @from.y, d_x, d_y, d)
+ end
+
+ private
+
+ def bresenham(p_x, p_y, d_x, d_y, d)
+ 0.upto([d_x, d_y].max).each_with_object([]) do |_, list|
+ list << Point.new(p_x, p_y)
+ p_x, p_y, d = next_step(p_x, p_y, d_x, d_y, d)
+ end
+ end
+
+ def next_step(p_x, p_y, d_x, d_y, d)
+ if @from.y <= @to.y
+ d_x < d_y ? first_case(p_x, p_y, d_x, d_y, d) : second_case(p_x, p_y, d_x, d_y, d)
+ else
+ d_x < d_y ? third_case(p_x, p_y, d_x, d_y, d) : fourth_case(p_x, p_y, d_x, d_y, d)
+ end
+ end
+
+ def first_case(p_x, p_y, d_x, d_y, d)
+ if d < 0
+ [p_x, p_y + 1, d + 2*d_x]
+ else
+ [p_x + 1, p_y + 1, d + 2*d_x - 2*d_y]
+ end
+ end
+
+ def second_case(p_x, p_y, d_x, d_y, d)
+ if d < 0
+ [p_x + 1, p_y, d + 2*d_y]
+ else
+ [p_x + 1, p_y + 1, d + 2*d_y - 2*d_x]
+ end
+ end
+
+ def third_case(p_x, p_y, d_x, d_y, d)
+ if d < 0
+ [p_x, p_y - 1, d + 2*d_x]
+ else
+ [p_x + 1, p_y - 1, d + 2*d_x - 2*d_y]
+ end
+ end
+
+ def fourth_case(p_x, p_y, d_x, d_y, d)
+ if d < 0
+ [p_x + 1, p_y, d + 2*d_y]
+ else
+ [p_x + 1, p_y - 1, d + 2*d_y - 2*d_x]
+ end
+ end
+ end
+
+ class Rectangle
+ attr_reader :left, :right, :top_left, :top_right, :bottom_left, :bottom_right
+
+ def initialize(point_a, point_b)
+ initialize_left_and_right(point_a, point_b)
+ initialize_skeptic_sucks
+ end
+
+ def each
+ top = Line.new(@top_left, @top_right).rasterize
+ bottom = Line.new(@bottom_left, @bottom_right).rasterize
+ left = Line.new(@top_left, @bottom_left).rasterize
+ right = Line.new(@top_right, @bottom_right).rasterize
+
+ (top + bottom + left + right).each { |point| yield point }
+ end
+
+ def to_s
+ "Rectangle(#{@top_left}, #{@top_right}, #{@bottom_left}, #{bottom_right})"
+ end
+
+ def hash
+ to_s.hash
+ end
+
+ def ==(other)
+ @top_left == other.top_left and @bottom_right == other.bottom_right
+ end
+
+ alias_method :eql?, :==
+
+ private
+
+ def initialize_left_and_right(point_a, point_b)
+ @left = point_a
+ @right = point_b
+ if point_a.x > point_b.x or point_a.x == point_b.x and point_a.y > point_b.y
+ @left, @right = @right, @left
+ end
+ end
+
+ def initialize_skeptic_sucks
+ @top_left = @left.y <= @right.y ? @left : Point.new(@left.x, @right.y)
+ @top_right = @right.y <= @left.y ? @right : Point.new(@right.x, @left.y)
+ @bottom_left = @left == @top_left ? Point.new(@left.x, @right.y) : @left
+ @bottom_right = @right == @top_right ? Point.new(@right.x, @left.y) : @right
+ end
+ end
+
+ class Pixel
+ attr_accessor :active
+
+ def initialize(active = false)
+ @active = active
+ end
+
+ def draw(renderer)
+ active ? renderer.visible : renderer.invisible
+ end
+ end
+
+ class Canvas
+ attr_reader :width, :height
+
+ def initialize(width, height)
+ @width = width
+ @height = height
+ @data = Array.new(height) { Array.new(width) { Pixel.new } }
+ end
+
+ def set_pixel(x, y)
+ @data[y][x].active = true
+ end
+
+ def pixel_at?(x, y)
+ @data[y][x].active
+ end
+
+ def draw(figure)
+ figure.each { |point| @data[point.y][point.x].active = true }
+ end
+
+ def render_as(renderer)
+ renderer.foreword + @data.map do |row|
+ rendered_row = row.map { |pixel| pixel.draw(renderer) }.reduce(:+)
+ rendered_row + (row != @data.last ? renderer.line_break : renderer.afterword)
+ end.reduce(:+)
+ end
+ end
+end
