Determining Max-Width of Responsive Images

Determining Max-Width of Responsive Images

# Get image's max-width:100%; in pixels
getMaxWidth = (img) ->
	maxWidth = undefined
  
	# Check if naturalWidth is supported
	if img.naturalWidth isnt `undefined`
		maxWidth = img.naturalWidth
  
	# Not supported, use in-memory solution as fallback
	else
		image = new Image()
		image.src = img.src
		maxWidth = image.width
  
	# Return the max-width
	maxWidth

# image has to be fully loaded before you can check its dimensions!
hasDimensions = (img) ->
	!!((img.complete and typeof img.naturalWidth isnt "undefined") or img.width)