Class: SmartImage::RatioCalculator

Inherits:
Object
  • Object
show all
Defined in:
lib/smart_image/ratio_calculator.rb

Defined Under Namespace

Classes: Size

Instance Method Summary collapse

Constructor Details

#initialize(options = {}) ⇒ RatioCalculator

Create a new RatioCalculator object with the given options



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# File 'lib/smart_image/ratio_calculator.rb', line 4

def initialize(options = {})
  @options = options
end

Instance Method Details

#size(options = {}) ⇒ Object

Calculate the resulting size given a particular set of contraints



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# File 'lib/smart_image/ratio_calculator.rb', line 9

def size(options = {})
  opts = @options.merge(options)

  source = Size.new opts[:source_width], opts[:source_height]
  bounds = Size.new opts[:dest_width],   opts[:dest_height]

  # Calculate what the width would be if we matched the dest height
  naive_width = bounds.height * source.aspect_ratio

  # If it fits, use it!
  if naive_width <= bounds.width
    width  = naive_width
    height = naive_width / source.aspect_ratio
  # Otherwise, the height must fit
  else
    height = bounds.width / source.aspect_ratio
    width  = height * source.aspect_ratio
  end

  return Size.new(width, height)
end