Class: PdfWatermark::WaterMark::Single

Inherits:
Base
  • Object
show all
Defined in:
lib/pdf_watermark/water_mark/single.rb

Instance Method Summary collapse

Constructor Details

#initialize(*args) ⇒ Single

Returns a new instance of Single.



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# File 'lib/pdf_watermark/water_mark/single.rb', line 6

def initialize(*args)
  super(*args)
end

Instance Method Details

#calculated_font_size(canvas, string, max_font, max_width) ⇒ Object 



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# File 'lib/pdf_watermark/water_mark/single.rb', line 40

def calculated_font_size(canvas, string, max_font, max_width)
  text_width = canvas.width_of(string, max_font)
  if text_width > max_width
    (max_width - canvas.graphics_state.character_spacing * string.size) / string.size
  else
    max_font
  end
end

#render ⇒ Object 



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# File 'lib/pdf_watermark/water_mark/single.rb', line 10

def render
  document.pages.each do |page|
    canvas = page.canvas(type: :overlay)
    canvas.fill_color(@options[:font_color])
    canvas.font(:watermark_font, size: 18)
    rad = deg_to_rad(@angle)

    if Math.tan(rad) < @content_height.to_f/@content_width.to_f
      max_text_width = (@content_width/Math.cos(rad)).abs
    else
      max_text_width = (@content_height/Math.sin(rad)).abs
    end
    # if user does not provide the font size, scale to fill the whole page
    if @font_size
      canvas.font_size(@font_size)
    else
      @font_size = calculated_font_size(canvas, @mark_string, @options[:max_font_size], max_text_width)
      canvas.font_size(@font_size)
      @x = (@content_width - canvas.width_of(@mark_string))/2 + @options[:margin][3]
      @y = @content_height / 2 + @options[:margin][2]
    end
    canvas.opacity(fill_alpha: @options[:transparent]) do
      canvas.rotate(@angle, origin: [@content_width/2, @content_height/2]) do
        canvas.text(@mark_string, at: [@x, @y])
      end
    end
  end
  document
end