Class: HexaPDF::Layout::ImageBox

Inherits:
Box
  • Object
show all
Defined in:
lib/hexapdf/layout/image_box.rb

Overview

An Image box object is used for displaying an image.

How an image is displayed inside an image box, depends on whether the width and/or height of the box has been set:

  • If one of them has been set, the other is adjusted to retain the image ratio.

  • If both have been set, both are used as is.

  • If neither has been set, the image is scaled to fit the available space.

Also see: HexaPDF::Content::Canvas#image

Instance Attribute Summary collapse

Attributes inherited from Box

#height, #style, #width

Instance Method Summary collapse

Methods inherited from Box

#content_height, #content_width, create, #draw, #empty?, #split

Constructor Details

#initialize(image, **kwargs) ⇒ ImageBox

Creates a new Image box object for the given image argument which needs to be an image object (e.g. returned by HexaPDF::Document::Images#add).



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# File 'lib/hexapdf/layout/image_box.rb', line 58

def initialize(image, **kwargs)
  super(**kwargs, &:unused_draw_block)
  @image = image
end

Instance Attribute Details

#image ⇒ Object (readonly)

The image that is shown in the box.



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# File 'lib/hexapdf/layout/image_box.rb', line 54

def image
  @image
end

Instance Method Details

#fit(available_width, available_height, _) ⇒ Object

Fits the image into the available space.



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# File 'lib/hexapdf/layout/image_box.rb', line 64

def fit(available_width, available_height, _)
  image_width = @image.width.to_f
  image_height = @image.height.to_f
  image_ratio = image_width / image_height

  if @initial_width > 0 && @initial_height > 0
    @width = @initial_width
    @height = @initial_height
  elsif @initial_width > 0
    @width = @initial_width
    @height = (@width - reserved_width) / image_ratio + reserved_height
  elsif @initial_height > 0
    @height = @initial_height
    @width = (@height - reserved_height) * image_ratio + reserved_width
  else
    rw = reserved_width
    rh = reserved_height
    ratio = [(available_width - rw) / image_width, (available_height - rh) / image_height].min
    @width = image_width * ratio + rw
    @height = image_height * ratio + rh
  end

  @width <= available_width && @height <= available_height
end