Module: Doohickey::SassExtensions::Gradients::Functions

Defined in:
lib/doohickey/sass_extensions/gradients.rb

Instance Method Summary collapse

Instance Method Details

#color_stops(*args) ⇒ Object 



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# File 'lib/doohickey/sass_extensions/gradients.rb', line 143

def color_stops(*args)
  List.new(*args.map do |arg|
    case arg
    when Sass::Script::Color
      ColorStop.new(arg)
    when Sass::Script::String
      # We get a string as the result of concatenation
      # So we have to reparse the expression
      color = stop = nil
      expr = Sass::Script::Parser.parse(arg.value, 0, 0)
      case expr
      when Sass::Script::Color
        color = expr
      when Sass::Script::Funcall
        color = expr
      when Sass::Script::Operation
        unless expr.instance_variable_get("@operator") == :concat
          # This should never happen.
          raise Sass::SyntaxError, "Couldn't parse a color stop from: #{arg.value}"
        end
        color = expr.instance_variable_get("@operand1")
        stop = expr.instance_variable_get("@operand2")
      else
        raise Sass::SyntaxError, "Couldn't parse a color stop from: #{arg.value}"
      end
      ColorStop.new(color, stop)
    else
      raise Sass::SyntaxError, "Not a valid color stop: #{arg}"
    end
  end)
end

#first_color_stop(color_list) ⇒ Object

Return the color of the first color stop



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# File 'lib/doohickey/sass_extensions/gradients.rb', line 65

def first_color_stop(color_list)
  color = color_list.values.first.color.inspect
  Sass::Script::String.new(color)
end

#grad_color_stops(color_list) ⇒ Object

returns color-stop() calls for use in webkit.



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# File 'lib/doohickey/sass_extensions/gradients.rb', line 71

def grad_color_stops(color_list)
  assert_list(color_list)
  normalize_stops!(color_list)
  max = color_list.values.last.stop
  color_stops = color_list.values.map do |pos|
    # have to convert absolute units to percentages for use in color stop functions.
    stop = pos.stop
    stop = stop.div(max).times(Sass::Script::Number.new(100,["%"])) if stop.numerator_units == max.numerator_units
    "color-stop(#{stop.inspect}, #{pos.color.inspect})"
  end
  Sass::Script::String.new(color_stops.join(", "))
end

#grad_end_position(color_list, radial = Sass::Script::Bool.new(false)) ⇒ Object

returns the end position of the gradient from the color stop



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# File 'lib/doohickey/sass_extensions/gradients.rb', line 85

def grad_end_position(color_list, radial = Sass::Script::Bool.new(false))
  assert_list(color_list)
  default = Sass::Script::Number.new(100)
  grad_position(color_list, Sass::Script::Number.new(color_list.values.size), default, radial)
end

#grad_opposite_position(position) ⇒ Object

returns the opposite position of a side or corner.



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# File 'lib/doohickey/sass_extensions/gradients.rb', line 49

def grad_opposite_position(position)
  opposite = position.value.split(/ +/).map do |pos|
    case pos
    when "top" then "bottom"
    when "bottom" then "top"
    when "left" then "right"
    when "right" then "left"
    when "center" then "center"
    else
      raise Sass::SyntaxError, "Cannot determine the opposite of #{pos}"
    end
  end
  Sass::Script::String.new(opposite.join(" "))
end

#grad_point(position) ⇒ Object

the given a position, return a point in percents



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# File 'lib/doohickey/sass_extensions/gradients.rb', line 117

def grad_point(position)
  position = position.value
  position = if position[" "]
    if position =~ /(top|bottom|center) (left|right|center)/
      "#{$2} #{$1}"
    else
      position
    end
  else
    case position
    when /top|bottom/
      "left #{position}"
    when /left|right/
      "#{position} top"
    else
      position
    end
  end
  Sass::Script::String.new(position.
    gsub(/top/, "0%").
    gsub(/bottom/, "100%").
    gsub(/left/,"0%").
    gsub(/right/,"100%").
    gsub(/center/, "50%"))
end

#grad_position(color_list, index, default, radial = Sass::Script::Bool.new(false)) ⇒ Object 



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# File 'lib/doohickey/sass_extensions/gradients.rb', line 91

def grad_position(color_list, index, default, radial = Sass::Script::Bool.new(false))
  assert_list(color_list)
  stop = color_list.values[index.value - 1].stop
  if stop && radial.to_bool
    orig_stop = stop
    if stop.unitless?
      if stop.value <= 1
        # A unitless number is assumed to be a percentage when it's between 0 and 1
        stop = stop.times(Sass::Script::Number.new(100, ["%"]))
      else
        # Otherwise, a unitless number is assumed to be in pixels
        stop = stop.times(Sass::Script::Number.new(1, ["px"]))
      end
    end
    if stop.numerator_units == ["%"] && color_list.values.last.stop && color_list.values.last.stop.numerator_units == ["px"]
      stop = stop.times(color_list.values.last.stop).div(Sass::Script::Number.new(100, ["%"]))
    end
    stop.div(Sass::Script::Number.new(1, stop.numerator_units, stop.denominator_units))
  elsif stop
    stop
  else
    default
  end
end