Module: MemeCaptain

Defined in:
lib/meme_captain/draw.rb,
lib/meme_captain/meme.rb,
lib/meme_captain/memebg.rb,
lib/meme_captain/caption.rb,
lib/meme_captain/version.rb,
lib/meme_captain/text_pos.rb,
lib/meme_captain/caption_choice.rb,
lib/meme_captain/image_list/watermark.rb

Defined Under Namespace

Modules: Draw, ImageList Classes: Caption, CaptionChoice, TextPos

Constant Summary collapse

VERSION = 
'0.3.0'

Class Method Summary collapse

Class Method Details

.meme(input, text_poss, options = {}) ⇒ Object

Create a meme image.

Input can be an IO object or a blob of data. text_poss is an enumerable of TextPos objects containing text, position and style options.

Options:

super_sample - work this many times larger before shrinking



14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
 
# File 'lib/meme_captain/meme.rb', line 14

def meme(input, text_poss, options={})
  img = Magick::ImageList.new
  if input.respond_to?(:read)
    img.from_blob(input.read)
  else
    img.from_blob(input)
  end

  img.auto_orient!

  super_sample = options[:super_sample] || 1.0

  text_layer = Magick::Image.new(
    img.page.width * super_sample, img.page.height * super_sample) {
    self.background_color = 'none'
  }

  text_poss.each do |text_pos|
    caption = Caption.new(text_pos.text)

    if caption.drawable?
      wrap_tries = (1..text_pos.max_lines).map { |num_lines|
        caption.wrap(num_lines).upcase.annotate_quote
      }.uniq

      text_x = (text_pos.x.is_a?(Float) ?
        img.page.width * text_pos.x : text_pos.x) * super_sample

      text_y = (text_pos.y.is_a?(Float) ?
        img.page.height * text_pos.y : text_pos.y) * super_sample

      text_width = (text_pos.width.is_a?(Float) ?
        img.page.width * text_pos.width : text_pos.width) * super_sample

      text_height = (text_pos.height.is_a?(Float) ?
        img.page.height * text_pos.height : text_pos.height) * super_sample

      min_pointsize = text_pos.min_pointsize * super_sample

      draw = Magick::Draw.new.extend(Draw)

      text_pos.draw_options.each do |k,v|
        # options that need to be scaled by super sample
        if [
          :stroke_width
          ].include?(k)
          v *= super_sample
        end
        draw.send("#{k}=", v)
      end

      choices = wrap_tries.map do |wrap_try|
        pointsize, metrics = draw.calc_pointsize(text_width, text_height,
          wrap_try, min_pointsize)

        CaptionChoice.new(pointsize, metrics, wrap_try, text_width,
          text_height)
      end

      choice = choices.max

      draw.pointsize = choice.pointsize

      draw.annotate text_layer, text_width, text_height, text_x, text_y,
        choice.text

      text_layer.virtual_pixel_method = Magick::TransparentVirtualPixelMethod
      text_layer = text_layer.blur_channel(text_pos.draw_options[:stroke_width] / 2.0,
                                           text_pos.draw_options[:stroke_width] / 4.0, Magick::OpacityChannel)

      draw.stroke = 'none'

      draw.annotate text_layer, text_width, text_height, text_x, text_y,
        choice.text
    end
  end

  if super_sample != 1
    text_layer.resize!(1.0 / super_sample)
    text_layer = text_layer.unsharp_mask
  end

  img.each do |frame|
    frame.composite!(text_layer, -frame.page.x, -frame.page.y,
      Magick::OverCompositeOp)
    frame.strip!
  end

  text_layer.destroy!

  img
end

.meme_top_bottom(input, top_text, bottom_text, options = {}) ⇒ Object

Shortcut to generate a typical meme with text at the top and bottom.



108
109
110
111
112
113
 
# File 'lib/meme_captain/meme.rb', line 108

def meme_top_bottom(input, top_text, bottom_text, options={})
  meme(input, [
    TextPos.new(top_text, 0.05, 0, 0.9, 0.25, options),
    TextPos.new(bottom_text, 0.05, 0.75, 0.9, 0.25, options)
    ])
end

.memebg(size, colors, num_rays, &block) ⇒ Object

Public: Generate a pie slice meme background.

size - The side length in pixels of the generated image. colors - An Array of color strings (any values that RMagick accepts). num_rays - The Fixnum of rays to create. block - An optiona block passed to Draw.new for specifying additional

draw options

Examples

memebg(400, %w{red orange yellow green blue indigo violet}, 20) {
  # draw options
  # self.stroke = 'white'
}.display

Returns a Magick::Image of the meme background.



23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
 
# File 'lib/meme_captain/memebg.rb', line 23

def memebg(size, colors, num_rays, &block)
  # make circle 5% too big to avoid empty space at corners from rounding
  # errors
  circle_radius = Math.sqrt(2 * ((size / 2.0) ** 2)) * 1.05

  side_len = 2 * circle_radius

  start_x = side_len
  start_y = circle_radius

  center = "#{circle_radius},#{circle_radius}"

  img = Magick::Image.new(side_len, side_len)

  color_cycle = colors.cycle

  (1..num_rays).each do |ray_index|
    ray_radius = 2 * Math::PI / num_rays * ray_index

    end_x = circle_radius + (Math.cos(ray_radius) * circle_radius)
    end_y = circle_radius - (Math.sin(ray_radius) * circle_radius)

    svg = "M#{center} L#{start_x},#{start_y} A#{center} 0 0,0 #{end_x},#{end_y} z"

    draw = Magick::Draw.new {
      instance_eval(&block)  if block_given?
      self.fill = color_cycle.next
    }

    draw.path svg
    draw.draw img

    start_x = end_x
    start_y = end_y
  end

  img.crop! Magick::CenterGravity, size, size
end