Module: PSD::Image::Export::PNG

Included in:
PSD::Image, Node::BuildPreview
Defined in:
lib/psd/image_exports/png.rb

Overview

PNG image export. This is the default export format.

Instance Method Summary collapse

Instance Method Details

#mask_to_png ⇒ Object 



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# File 'lib/psd/image_exports/png.rb', line 62

def mask_to_png
  return unless has_mask?

  png = ChunkyPNG::Canvas.new(@layer.mask.width.to_i, @layer.mask.height.to_i, ChunkyPNG::Color::TRANSPARENT)

  i = 0
  @layer.mask.height.times do |y|
    @layer.mask.width.times do |x|
      png[x, y] = ChunkyPNG::Color.grayscale(@mask_data[i])
      i += 1
    end
  end

  png
end

#save_as_png(file) ⇒ Object

Saves the PNG data to disk.



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# File 'lib/psd/image_exports/png.rb', line 79

def save_as_png(file)
  to_png.save(file, :fast_rgba)
end

#to_png ⇒ Object Also known as: export

Load the image pixels into a PNG file and return a reference to the data.



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# File 'lib/psd/image_exports/png.rb', line 9

def to_png
  PSD.logger.debug "Beginning PNG export"
  png = ChunkyPNG::Canvas.new(width.to_i, height.to_i, ChunkyPNG::Color::TRANSPARENT)

  i = 0
  height.times do |y|
    width.times do |x|
      png[x,y] = @pixel_data[i]
      i += 1
    end
  end

  png
end

#to_png_with_mask ⇒ Object 



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# File 'lib/psd/image_exports/png.rb', line 25

def to_png_with_mask
  return to_png unless has_mask?

  PSD.logger.debug "Beginning PNG export with mask"
  
  # We generate the preview at the document size instead to make applying the mask
  # significantly easier.
  width = @layer.header.width.to_i
  height = @layer.header.height.to_i
  png = ChunkyPNG::Canvas.new(width, height, ChunkyPNG::Color::TRANSPARENT)

  i = 0
  @layer.height.times do |y|
    @layer.width.times do |x|
      png[x + @layer.left, y + @layer.top] = @pixel_data[i]
      i += 1
    end
  end
  
  # Now we apply the mask
  i = 0
  @layer.mask.height.times do |y|
    @layer.mask.width.times do |x|
      offset_x = @layer.mask.left + x
      offset_y = @layer.mask.top + y

      color = ChunkyPNG::Color.to_truecolor_alpha_bytes(png.get_pixel(offset_x, offset_y))
      color[3] = color[3] * @mask_data[i] / 255

      png.set_pixel(offset_x, offset_y, ChunkyPNG::Color.rgba(*color))
      i += 1
    end
  end

  png.crop!(@layer.left, @layer.top, @layer.width.to_i, @layer.height.to_i)
end