Class: Sass::Script::Value::Color

Inherits:
Base
  • Object
show all
Defined in:
lib/sass/script/value/color.rb

Overview

A SassScript object representing a CSS color.

A color may be represented internally as RGBA, HSLA, or both. It's originally represented as whatever its input is; if it's created with RGB values, it's represented as RGBA, and if it's created with HSL values, it's represented as HSLA. Once a property is accessed that requires the other representation -- for example, #red for an HSL color -- that component is calculated and cached.

The alpha channel of a color is independent of its RGB or HSL representation. It's always stored, as 1 if nothing else is specified. If only the alpha channel is modified using #with, the cached RGB and HSL values are retained.

Constant Summary collapse

ALTERNATE_COLOR_NAMES = 
Sass::Util.map_vals({
    'aqua'                 => 0x00FFFFFF,
    'darkgrey'             => 0xA9A9A9FF,
    'darkslategrey'        => 0x2F4F4FFF,
    'dimgrey'              => 0x696969FF,
    'fuchsia'              => 0xFF00FFFF,
    'grey'                 => 0x808080FF,
    'lightgrey'            => 0xD3D3D3FF,
    'lightslategrey'       => 0x778899FF,
    'slategrey'            => 0x708090FF,
}, &method(:int_to_rgba))
COLOR_NAMES =

A hash from color names to [red, green, blue] value arrays.

Sass::Util.map_vals({
   'aliceblue'            => 0xF0F8FFFF,
   'antiquewhite'         => 0xFAEBD7FF,
   'aquamarine'           => 0x7FFFD4FF,
   'azure'                => 0xF0FFFFFF,
   'beige'                => 0xF5F5DCFF,
   'bisque'               => 0xFFE4C4FF,
   'black'                => 0x000000FF,
   'blanchedalmond'       => 0xFFEBCDFF,
   'blue'                 => 0x0000FFFF,
   'blueviolet'           => 0x8A2BE2FF,
   'brown'                => 0xA52A2AFF,
   'burlywood'            => 0xDEB887FF,
   'cadetblue'            => 0x5F9EA0FF,
   'chartreuse'           => 0x7FFF00FF,
   'chocolate'            => 0xD2691EFF,
   'coral'                => 0xFF7F50FF,
   'cornflowerblue'       => 0x6495EDFF,
   'cornsilk'             => 0xFFF8DCFF,
   'crimson'              => 0xDC143CFF,
   'cyan'                 => 0x00FFFFFF,
   'darkblue'             => 0x00008BFF,
   'darkcyan'             => 0x008B8BFF,
   'darkgoldenrod'        => 0xB8860BFF,
   'darkgray'             => 0xA9A9A9FF,
   'darkgreen'            => 0x006400FF,
   'darkkhaki'            => 0xBDB76BFF,
   'darkmagenta'          => 0x8B008BFF,
   'darkolivegreen'       => 0x556B2FFF,
   'darkorange'           => 0xFF8C00FF,
   'darkorchid'           => 0x9932CCFF,
   'darkred'              => 0x8B0000FF,
   'darksalmon'           => 0xE9967AFF,
   'darkseagreen'         => 0x8FBC8FFF,
   'darkslateblue'        => 0x483D8BFF,
   'darkslategray'        => 0x2F4F4FFF,
   'darkturquoise'        => 0x00CED1FF,
   'darkviolet'           => 0x9400D3FF,
   'deeppink'             => 0xFF1493FF,
   'deepskyblue'          => 0x00BFFFFF,
   'dimgray'              => 0x696969FF,
   'dodgerblue'           => 0x1E90FFFF,
   'firebrick'            => 0xB22222FF,
   'floralwhite'          => 0xFFFAF0FF,
   'forestgreen'          => 0x228B22FF,
   'gainsboro'            => 0xDCDCDCFF,
   'ghostwhite'           => 0xF8F8FFFF,
   'gold'                 => 0xFFD700FF,
   'goldenrod'            => 0xDAA520FF,
   'gray'                 => 0x808080FF,
   'green'                => 0x008000FF,
   'greenyellow'          => 0xADFF2FFF,
   'honeydew'             => 0xF0FFF0FF,
   'hotpink'              => 0xFF69B4FF,
   'indianred'            => 0xCD5C5CFF,
   'indigo'               => 0x4B0082FF,
   'ivory'                => 0xFFFFF0FF,
   'khaki'                => 0xF0E68CFF,
   'lavender'             => 0xE6E6FAFF,
   'lavenderblush'        => 0xFFF0F5FF,
   'lawngreen'            => 0x7CFC00FF,
   'lemonchiffon'         => 0xFFFACDFF,
   'lightblue'            => 0xADD8E6FF,
   'lightcoral'           => 0xF08080FF,
   'lightcyan'            => 0xE0FFFFFF,
   'lightgoldenrodyellow' => 0xFAFAD2FF,
   'lightgreen'           => 0x90EE90FF,
   'lightgray'            => 0xD3D3D3FF,
   'lightpink'            => 0xFFB6C1FF,
   'lightsalmon'          => 0xFFA07AFF,
   'lightseagreen'        => 0x20B2AAFF,
   'lightskyblue'         => 0x87CEFAFF,
   'lightslategray'       => 0x778899FF,
   'lightsteelblue'       => 0xB0C4DEFF,
   'lightyellow'          => 0xFFFFE0FF,
   'lime'                 => 0x00FF00FF,
   'limegreen'            => 0x32CD32FF,
   'linen'                => 0xFAF0E6FF,
   'magenta'              => 0xFF00FFFF,
   'maroon'               => 0x800000FF,
   'mediumaquamarine'     => 0x66CDAAFF,
   'mediumblue'           => 0x0000CDFF,
   'mediumorchid'         => 0xBA55D3FF,
   'mediumpurple'         => 0x9370DBFF,
   'mediumseagreen'       => 0x3CB371FF,
   'mediumslateblue'      => 0x7B68EEFF,
   'mediumspringgreen'    => 0x00FA9AFF,
   'mediumturquoise'      => 0x48D1CCFF,
   'mediumvioletred'      => 0xC71585FF,
   'midnightblue'         => 0x191970FF,
   'mintcream'            => 0xF5FFFAFF,
   'mistyrose'            => 0xFFE4E1FF,
   'moccasin'             => 0xFFE4B5FF,
   'navajowhite'          => 0xFFDEADFF,
   'navy'                 => 0x000080FF,
   'oldlace'              => 0xFDF5E6FF,
   'olive'                => 0x808000FF,
   'olivedrab'            => 0x6B8E23FF,
   'orange'               => 0xFFA500FF,
   'orangered'            => 0xFF4500FF,
   'orchid'               => 0xDA70D6FF,
   'palegoldenrod'        => 0xEEE8AAFF,
   'palegreen'            => 0x98FB98FF,
   'paleturquoise'        => 0xAFEEEEFF,
   'palevioletred'        => 0xDB7093FF,
   'papayawhip'           => 0xFFEFD5FF,
   'peachpuff'            => 0xFFDAB9FF,
   'peru'                 => 0xCD853FFF,
   'pink'                 => 0xFFC0CBFF,
   'plum'                 => 0xDDA0DDFF,
   'powderblue'           => 0xB0E0E6FF,
   'purple'               => 0x800080FF,
   'red'                  => 0xFF0000FF,
   'rosybrown'            => 0xBC8F8FFF,
   'royalblue'            => 0x4169E1FF,
   'saddlebrown'          => 0x8B4513FF,
   'salmon'               => 0xFA8072FF,
   'sandybrown'           => 0xF4A460FF,
   'seagreen'             => 0x2E8B57FF,
   'seashell'             => 0xFFF5EEFF,
   'sienna'               => 0xA0522DFF,
   'silver'               => 0xC0C0C0FF,
   'skyblue'              => 0x87CEEBFF,
   'slateblue'            => 0x6A5ACDFF,
   'slategray'            => 0x708090FF,
   'snow'                 => 0xFFFAFAFF,
   'springgreen'          => 0x00FF7FFF,
   'steelblue'            => 0x4682B4FF,
   'tan'                  => 0xD2B48CFF,
   'teal'                 => 0x008080FF,
   'thistle'              => 0xD8BFD8FF,
   'tomato'               => 0xFF6347FF,
   'transparent'          => 0x00000000,
   'turquoise'            => 0x40E0D0FF,
   'violet'               => 0xEE82EEFF,
   'wheat'                => 0xF5DEB3FF,
   'white'                => 0xFFFFFFFF,
   'whitesmoke'           => 0xF5F5F5FF,
   'yellow'               => 0xFFFF00FF,
   'yellowgreen'          => 0x9ACD32FF
}, &method(:int_to_rgba))
COLOR_NAMES_REVERSE =

A hash from [red, green, blue, alpha] value arrays to color names.

COLOR_NAMES.invert.freeze

Instance Attribute Summary

Attributes inherited from Base

#options, #source_range, #value

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Base

#==, #_perform, #assert_int!, #eql?, #neq, #null?, #separator, #single_eq, #to_a, #to_bool, #to_h, #to_i, #unary_div, #unary_minus, #unary_not, #unary_plus

Constructor Details

#initialize(attrs) ⇒ Color #initialize(rgba) ⇒ Color

Constructs an RGB or HSL color object, optionally with an alpha channel.

The RGB values must be between 0 and 255. The saturation and lightness values must be between 0 and 100. The alpha value must be between 0 and 1.

Overloads:

  • #initialize(attrs) ⇒ Color

    The attributes are specified as a hash. This hash must contain either :hue, :saturation, and :value keys, or :red, :green, and :blue keys. It cannot contain both HSL and RGB keys. It may also optionally contain an :alpha key.

    Parameters:

    • attrs ({Symbol => Numeric}) —

      A hash of color attributes to values

    Raises:

    • (ArgumentError) —

      if not enough attributes are specified, or both RGB and HSL attributes are specified

  • #initialize(rgba) ⇒ Color

    The attributes are specified as an array. This overload only supports RGB or RGBA colors.

    Parameters:

    • rgba (Array<Numeric>) —

      A three- or four-element array of the red, green, blue, and optionally alpha values (respectively) of the color

    Raises:

    • (ArgumentError) —

      if not enough attributes are specified

Raises:



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# File 'lib/sass/script/value/color.rb', line 218

def initialize(attrs, allow_both_rgb_and_hsl = false)
  super(nil)

  if attrs.is_a?(Array)
    unless (3..4).include?(attrs.size)
      raise ArgumentError.new("Color.new(array) expects a three- or four-element array")
    end

    red, green, blue = attrs[0...3].map {|c| c.to_i}
    @attrs = {:red => red, :green => green, :blue => blue}
    @attrs[:alpha] = attrs[3] ? attrs[3].to_f : 1
  else
    attrs = attrs.reject {|k, v| v.nil?}
    hsl = [:hue, :saturation, :lightness] & attrs.keys
    rgb = [:red, :green, :blue] & attrs.keys
    if !allow_both_rgb_and_hsl && !hsl.empty? && !rgb.empty?
      raise ArgumentError.new("Color.new(hash) may not have both HSL and RGB keys specified")
    elsif hsl.empty? && rgb.empty?
      raise ArgumentError.new("Color.new(hash) must have either HSL or RGB keys specified")
    elsif !hsl.empty? && hsl.size != 3
      raise ArgumentError.new("Color.new(hash) must have all three HSL values specified")
    elsif !rgb.empty? && rgb.size != 3
      raise ArgumentError.new("Color.new(hash) must have all three RGB values specified")
    end

    @attrs = attrs
    @attrs[:hue] %= 360 if @attrs[:hue]
    @attrs[:alpha] ||= 1
  end

  [:red, :green, :blue].each do |k|
    next if @attrs[k].nil?
    @attrs[k] = @attrs[k].to_i
    Sass::Util.check_range("#{k.to_s.capitalize} value", 0..255, @attrs[k])
  end

  [:saturation, :lightness].each do |k|
    next if @attrs[k].nil?
    value = Number.new(@attrs[k], ['%']) # Get correct unit for error messages
    @attrs[k] = Sass::Util.check_range("#{k.to_s.capitalize}", 0..100, value, '%')
  end

  @attrs[:alpha] = Sass::Util.check_range("Alpha channel", 0..1, @attrs[:alpha])
end

Class Method Details

.from_hex(hex_string, alpha = nil) ⇒ Color

Create a new color from a valid CSS hex string.

The leading hash is optional.

Returns:



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# File 'lib/sass/script/value/color.rb', line 268

def self.from_hex(hex_string, alpha = nil)
  unless hex_string =~ /^#?([0-9a-f]{2})([0-9a-f]{2})([0-9a-f]{2})$/i ||
         hex_string =~ /^#?([0-9a-f])([0-9a-f])([0-9a-f])$/i
    raise ArgumentError.new("#{hex_string.inspect} is not a valid hex color.")
  end
  red   = $1.ljust(2, $1).to_i(16)
  green = $2.ljust(2, $2).to_i(16)
  blue  = $3.ljust(2, $3).to_i(16)
  attrs = {:red => red, :green => green, :blue => blue}
  attrs[:alpha] = alpha if alpha
  new(attrs)
end

Instance Method Details

#alpha ⇒ Fixnum

The alpha channel (opacity) of the color. This is 1 unless otherwise defined.

Returns:

  • (Fixnum) 


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# File 'lib/sass/script/value/color.rb', line 333

def alpha
  @attrs[:alpha].to_f
end

#alpha? ⇒ Boolean

Returns whether this color object is translucent; that is, whether the alpha channel is non-1.

Returns:

  • (Boolean) 


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# File 'lib/sass/script/value/color.rb', line 341

def alpha?
  alpha < 1
end

#blue ⇒ Fixnum

The blue component of the color.

Returns:

  • (Fixnum) 


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# File 'lib/sass/script/value/color.rb', line 300

def blue
  hsl_to_rgb!
  @attrs[:blue]
end

#div(other) ⇒ Color

The SassScript / operation. Its functionality depends on the type of its argument:

Number : Divides each of the RGB color channels by the number.

Sass::Script::Value::Color : Divides each of this color's RGB color channels by the other color's.

Sass::Script::Value : See Base#div.

Parameters:

  • other (Value) —

    The right-hand side of the operator

Returns:

  • (Color) —

    The resulting color

Raises:



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# File 'lib/sass/script/value/color.rb', line 515

def div(other)
  if other.is_a?(Sass::Script::Value::Number) ||
      other.is_a?(Sass::Script::Value::Color)
    piecewise(other, :/)
  else
    super
  end
end

#eq(other) ⇒ Bool

The SassScript == operation. Note that this returns a Bool object, not a Ruby boolean.

Parameters:

  • other (Value) —

    The right-hand side of the operator

Returns:

  • (Bool) —

    True if this value is the same as the other, false otherwise



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# File 'lib/sass/script/value/color.rb', line 384

def eq(other)
  Sass::Script::Value::Bool.new(
    other.is_a?(Color) && rgb == other.rgb && alpha == other.alpha)
end

#green ⇒ Fixnum

The green component of the color.

Returns:

  • (Fixnum) 


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# File 'lib/sass/script/value/color.rb', line 292

def green
  hsl_to_rgb!
  @attrs[:green]
end

#hash 



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# File 'lib/sass/script/value/color.rb', line 389

def hash
  [rgb, alpha].hash
end

#hsl ⇒ Array<Fixnum>

Returns the hue, saturation, and lightness components of the color.

Returns:

  • (Array<Fixnum>) —

    A frozen three-element array of the hue, saturation, and lightness values (respectively) of the color



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# File 'lib/sass/script/value/color.rb', line 365

def hsl
  [hue, saturation, lightness].freeze
end

#hsla ⇒ Array<Fixnum>

Returns the hue, saturation, lightness, and alpha components of the color.

Returns:

  • (Array<Fixnum>) —

    A frozen four-element array of the hue, saturation, lightness, and alpha values (respectively) of the color



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# File 'lib/sass/script/value/color.rb', line 373

def hsla
  [hue, saturation, lightness].freeze
end

#hue ⇒ Numeric

The hue component of the color.

Returns:

  • (Numeric) 


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# File 'lib/sass/script/value/color.rb', line 308

def hue
  rgb_to_hsl!
  @attrs[:hue]
end

#inspect ⇒ String

Returns a string representation of the color.

Returns:



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# File 'lib/sass/script/value/color.rb', line 560

def inspect
  alpha? ? rgba_str : hex_str
end

#lightness ⇒ Numeric

The lightness component of the color.

Returns:

  • (Numeric) 


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# File 'lib/sass/script/value/color.rb', line 324

def lightness
  rgb_to_hsl!
  @attrs[:lightness]
end

#minus(other) ⇒ Color

The SassScript - operation. Its functionality depends on the type of its argument:

Number : Subtracts the number from each of the RGB color channels.

Sass::Script::Value::Color : Subtracts each of the other color's RGB color channels from this color's.

Sass::Script::Value : See Base#minus.

Parameters:

  • other (Value) —

    The right-hand side of the operator

Returns:

  • (Color) —

    The resulting color

Raises:



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# File 'lib/sass/script/value/color.rb', line 472

def minus(other)
  if other.is_a?(Sass::Script::Value::Number) || other.is_a?(Sass::Script::Value::Color)
    piecewise(other, :-)
  else
    super
  end
end

#mod(other) ⇒ Color

The SassScript % operation. Its functionality depends on the type of its argument:

Number : Takes each of the RGB color channels module the number.

Sass::Script::Value::Color : Takes each of this color's RGB color channels modulo the other color's.

Parameters:

  • other (Number, Color) —

    The right-hand side of the operator

Returns:

  • (Color) —

    The resulting color

Raises:



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# File 'lib/sass/script/value/color.rb', line 536

def mod(other)
  if other.is_a?(Sass::Script::Value::Number) ||
      other.is_a?(Sass::Script::Value::Color)
    piecewise(other, :%)
  else
    raise NoMethodError.new(nil, :mod)
  end
end

#plus(other) ⇒ Color

The SassScript + operation. Its functionality depends on the type of its argument:

Number : Adds the number to each of the RGB color channels.

Sass::Script::Value::Color : Adds each of the RGB color channels together.

Sass::Script::Value : See Base#plus.

Parameters:

  • other (Value) —

    The right-hand side of the operator

Returns:

  • (Color) —

    The resulting color

Raises:



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# File 'lib/sass/script/value/color.rb', line 449

def plus(other)
  if other.is_a?(Sass::Script::Value::Number) || other.is_a?(Sass::Script::Value::Color)
    piecewise(other, :+)
  else
    super
  end
end

#red ⇒ Fixnum

The red component of the color.

Returns:

  • (Fixnum) 


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# File 'lib/sass/script/value/color.rb', line 284

def red
  hsl_to_rgb!
  @attrs[:red]
end

#rgb ⇒ Array<Fixnum>

Returns the red, green, and blue components of the color.

Returns:

  • (Array<Fixnum>) —

    A frozen three-element array of the red, green, and blue values (respectively) of the color



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# File 'lib/sass/script/value/color.rb', line 349

def rgb
  [red, green, blue].freeze
end

#rgba ⇒ Array<Fixnum>

Returns the red, green, blue, and alpha components of the color.

Returns:

  • (Array<Fixnum>) —

    A frozen four-element array of the red, green, blue, and alpha values (respectively) of the color



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# File 'lib/sass/script/value/color.rb', line 357

def rgba
  [red, green, blue, alpha].freeze
end

#saturation ⇒ Numeric

The saturation component of the color.

Returns:

  • (Numeric) 


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# File 'lib/sass/script/value/color.rb', line 316

def saturation
  rgb_to_hsl!
  @attrs[:saturation]
end

#times(other) ⇒ Color

The SassScript * operation. Its functionality depends on the type of its argument:

Number : Multiplies the number by each of the RGB color channels.

Sass::Script::Value::Color : Multiplies each of the RGB color channels together.

Parameters:

  • other (Number, Color) —

    The right-hand side of the operator

Returns:

  • (Color) —

    The resulting color

Raises:



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# File 'lib/sass/script/value/color.rb', line 492

def times(other)
  if other.is_a?(Sass::Script::Value::Number) || other.is_a?(Sass::Script::Value::Color)
    piecewise(other, :*)
  else
    raise NoMethodError.new(nil, :times)
  end
end

#to_s(opts = {}) ⇒ String Also known as: to_sass

Returns a string representation of the color. This is usually the color's hex value, but if the color has a name that's used instead.

Returns:

  • (String) —

    The string representation



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# File 'lib/sass/script/value/color.rb', line 550

def to_s(opts = {})
  return smallest if options[:style] == :compressed
  return COLOR_NAMES_REVERSE[rgba] if COLOR_NAMES_REVERSE[rgba]
  alpha? ? rgba_str : hex_str
end

#with(attrs) ⇒ Color

Returns a copy of this color with one or more channels changed. RGB or HSL colors may be changed, but not both at once.

For example:

Color.new([10, 20, 30]).with(:blue => 40)
  #=> rgb(10, 40, 30)
Color.new([126, 126, 126]).with(:red => 0, :green => 255)
  #=> rgb(0, 255, 126)
Color.new([255, 0, 127]).with(:saturation => 60)
  #=> rgb(204, 51, 127)
Color.new([1, 2, 3]).with(:alpha => 0.4)
  #=> rgba(1, 2, 3, 0.4)

Parameters:

  • attrs ({Symbol => Numeric}) —

    A map of channel names (:red, :green, :blue, :hue, :saturation, :lightness, or :alpha) to values

Returns:

  • (Color) —

    The new Color object

Raises:

  • (ArgumentError) —

    if both RGB and HSL keys are specified



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# File 'lib/sass/script/value/color.rb', line 412

def with(attrs)
  attrs = attrs.reject {|k, v| v.nil?}
  hsl = !([:hue, :saturation, :lightness] & attrs.keys).empty?
  rgb = !([:red, :green, :blue] & attrs.keys).empty?
  if hsl && rgb
    raise ArgumentError.new("Cannot specify HSL and RGB values for a color at the same time")
  end

  if hsl
    [:hue, :saturation, :lightness].each {|k| attrs[k] ||= send(k)}
  elsif rgb
    [:red, :green, :blue].each {|k| attrs[k] ||= send(k)}
  else
    # If we're just changing the alpha channel,
    # keep all the HSL/RGB stuff we've calculated
    attrs = @attrs.merge(attrs)
  end
  attrs[:alpha] ||= alpha

  Color.new(attrs, :allow_both_rgb_and_hsl)
end