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.
A hash from color names to `[red, green, blue]` value arrays.
A hash from `[red, green, blue]` value arrays to color names.
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.
@raise [Sass::SyntaxError] if any color value isn’t in the specified range
@overload initialize(attrs)
The attributes are specified as a hash. This hash must contain either %x:hue`, %x:saturation`, and %x:value` keys, or %x:red`, %x:green`, and %x:blue` keys. It cannot contain both HSL and RGB keys. It may also optionally contain an %x:alpha` key. @param attrs [{Symbol => Numeric}] A hash of color attributes to values @raise [ArgumentError] if not enough attributes are specified, or both RGB and HSL attributes are specified
@overload initialize(rgba)
The attributes are specified as an array. This overload only supports RGB or RGBA colors. @param rgba [Array<Numeric>] A three- or four-element array of the red, green, blue, and optionally alpha values (respectively) of the color @raise [ArgumentError] if not enough attributes are specified
# File lib/sass/script/color.rb, line 202 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
The alpha channel (opacity) of the color. This is 1 unless otherwise defined.
@return [Fixnum]
# File lib/sass/script/color.rb, line 299 def alpha @attrs[:alpha] end
Returns whether this color object is translucent; that is, whether the alpha channel is non-1.
@return [Boolean]
# File lib/sass/script/color.rb, line 307 def alpha? alpha < 1 end
The blue component of the color.
@return [Fixnum]
# File lib/sass/script/color.rb, line 266 def blue hsl_to_rgb! @attrs[:blue] end
The SassScript `/` operation. Its functionality depends on the type of its argument:
{Number} : Divides each of the RGB color channels by the number.
{Color} : Divides each of this color’s RGB color channels by the other color’s.
{Literal} : See {Sass::Script::Literal#div}.
@param other [Literal] The right-hand side of the operator @return [Color] The resulting color @raise [Sass::SyntaxError] if `other` is a number with units
# File lib/sass/script/color.rb, line 461 def div(other) if other.is_a?(Sass::Script::Number) || other.is_a?(Sass::Script::Color) piecewise(other, :/) else super end end
The SassScript `==` operation. **Note that this returns a {Sass::Script::Bool} object, not a Ruby boolean**.
@param other [Literal] The right-hand side of the operator @return [Bool] True if this literal is the same as the other,
false otherwise
# File lib/sass/script/color.rb, line 334 def eq(other) Sass::Script::Bool.new( other.is_a?(Color) && rgb == other.rgb && alpha == other.alpha) end
The green component of the color.
@return [Fixnum]
# File lib/sass/script/color.rb, line 258 def green hsl_to_rgb! @attrs[:green] end
Returns the hue, saturation, and lightness components of the color.
@return [Array<Fixnum>] A frozen three-element array of the
hue, saturation, and lightness values (respectively) of the color
# File lib/sass/script/color.rb, line 323 def hsl [hue, saturation, lightness].freeze end
The hue component of the color.
@return [Numeric]
# File lib/sass/script/color.rb, line 274 def hue rgb_to_hsl! @attrs[:hue] end
Returns a string representation of the color.
@return [String] The hex value
# File lib/sass/script/color.rb, line 505 def inspect alpha? ? rgba_str : hex_str end
The lightness component of the color.
@return [Numeric]
# File lib/sass/script/color.rb, line 290 def lightness rgb_to_hsl! @attrs[:lightness] end
The SassScript `-` operation. Its functionality depends on the type of its argument:
{Number} : Subtracts the number from each of the RGB color channels.
{Color} : Subtracts each of the other color’s RGB color channels from this color’s.
{Literal} : See {Sass::Script::Literal#minus}.
@param other [Literal] The right-hand side of the operator @return [Color] The resulting color @raise [Sass::SyntaxError] if `other` is a number with units
# File lib/sass/script/color.rb, line 418 def minus(other) if other.is_a?(Sass::Script::Number) || other.is_a?(Sass::Script::Color) piecewise(other, :-) else super end end
The SassScript `%` operation. Its functionality depends on the type of its argument:
{Number} : Takes each of the RGB color channels module the number.
{Color} : Takes each of this color’s RGB color channels modulo the other color’s.
@param other [Number, Color] The right-hand side of the operator @return [Color] The resulting color @raise [Sass::SyntaxError] if `other` is a number with units
# File lib/sass/script/color.rb, line 481 def mod(other) if other.is_a?(Sass::Script::Number) || other.is_a?(Sass::Script::Color) piecewise(other, :%) else raise NoMethodError.new(nil, :mod) end end
The SassScript `+` operation. Its functionality depends on the type of its argument:
{Number} : Adds the number to each of the RGB color channels.
{Color} : Adds each of the RGB color channels together.
{Literal} : See {Sass::Script::Literal#plus}.
@param other [Literal] The right-hand side of the operator @return [Color] The resulting color @raise [Sass::SyntaxError] if `other` is a number with units
# File lib/sass/script/color.rb, line 395 def plus(other) if other.is_a?(Sass::Script::Number) || other.is_a?(Sass::Script::Color) piecewise(other, :+) else super end end
The red component of the color.
@return [Fixnum]
# File lib/sass/script/color.rb, line 250 def red hsl_to_rgb! @attrs[:red] end
Returns the red, green, and blue components of the color.
@return [Array<Fixnum>] A frozen three-element array of the red, green, and blue
values (respectively) of the color
# File lib/sass/script/color.rb, line 315 def rgb [red, green, blue].freeze end
The saturation component of the color.
@return [Numeric]
# File lib/sass/script/color.rb, line 282 def saturation rgb_to_hsl! @attrs[:saturation] end
The SassScript `*` operation. Its functionality depends on the type of its argument:
{Number} : Multiplies the number by each of the RGB color channels.
{Color} : Multiplies each of the RGB color channels together.
@param other [Number, Color] The right-hand side of the operator @return [Color] The resulting color @raise [Sass::SyntaxError] if `other` is a number with units
# File lib/sass/script/color.rb, line 438 def times(other) if other.is_a?(Sass::Script::Number) || other.is_a?(Sass::Script::Color) piecewise(other, :*) else raise NoMethodError.new(nil, :times) end end
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.
@return [String] The string representation
# File lib/sass/script/color.rb, line 494 def to_s(opts = {}) return rgba_str if alpha? return smallest if options[:style] == :compressed return COLOR_NAMES_REVERSE[rgb] if COLOR_NAMES_REVERSE[rgb] hex_str end
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)
@param attrs [{Symbol => Numeric}]
A map of channel names (`:red`, `:green`, `:blue`, `:hue`, `:saturation`, `:lightness`, or `:alpha`) to values
@return [Color] The new Color object @raise [ArgumentError] if both RGB and HSL keys are specified
# File lib/sass/script/color.rb, line 358 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