    # File lib/compass/sass_extensions/sprites/layout_methods.rb, line 84
            def calculate_smart_positions
              fitter = ::Compass::SassExtensions::Sprites::RowFitter.new(@images)
              current_y = 0
              fitter.fit!.each do |row|
                current_x = 0
                row.images.each_with_index do |image, index|
                  image.left = current_x
                  image.top = current_y
                  current_x += image.width
                end
                current_y += row.height
              end
              @width = fitter.width
              @height = fitter.height
            end