Class: Color::HSL
- Inherits:
-
Object
- Object
- Color::HSL
- Defined in:
- lib/color/hsl.rb
Overview
An HSL colour object. Internally, the hue (#h), saturation (#s), and luminosity/lightness (#l) values are dealt with as fractional values in the range 0..1.
Class Method Summary collapse
-
.from_fraction(h = 0.0, s = 0.0, l = 0.0) ⇒ Object
Creates an HSL colour object from fractional values 0..1.
Instance Method Summary collapse
-
#==(other) ⇒ Object
Compares the other colour to this one.
-
#brightness ⇒ Object
Returns the luminosity (#l) of the colour.
-
#css_hsl ⇒ Object
Present the colour as an HSL HTML/CSS colour string (e.g., “hsl(180, 25%, 35%)”).
-
#css_hsla ⇒ Object
Present the colour as an HSLA (with alpha) HTML/CSS colour string (e.g., “hsla(180, 25%, 35%, 1)”).
-
#css_rgb ⇒ Object
Present the colour as an RGB HTML/CSS colour string (e.g., “rgb(0%, 50%, 100%)”).
-
#css_rgba ⇒ Object
Present the colour as an RGBA (with alpha) HTML/CSS colour string (e.g., “rgb(0%, 50%, 100%, 1)”).
-
#h ⇒ Object
Returns the hue of the colour in the range 0.0 ..
-
#h=(hh) ⇒ Object
Sets the hue of the colour in the range 0.0 ..
-
#html ⇒ Object
Present the colour as an HTML/CSS colour string.
-
#hue ⇒ Object
Returns the hue of the colour in degrees.
-
#hue=(hh) ⇒ Object
Sets the hue of the colour in degrees.
-
#initialize(h = 0, s = 0, l = 0) ⇒ HSL
constructor
Creates an HSL colour object from the standard values of degrees and percentages (e.g., 145 deg, 30%, 50%).
- #inspect ⇒ Object
-
#l ⇒ Object
Returns the luminosity of the colour in the range 0.0 ..
-
#l=(ll) ⇒ Object
Sets the luminosity of the colour in the ragne 0.0 ..
-
#luminosity ⇒ Object
(also: #lightness)
Returns the percentage of luminosity of the colour.
-
#luminosity=(ll) ⇒ Object
(also: #lightness=)
Sets the percentage of luminosity of the colour.
-
#mix_with(color, mix_percent = 0.5) ⇒ Object
Mix the mask colour (which will be converted to an HSL colour) with the current colour at the stated mix percentage as a decimal value.
-
#s ⇒ Object
Returns the saturation of the colour in the range 0.0 ..
-
#s=(ss) ⇒ Object
Sets the saturation of the colour in the ragne 0.0 ..
-
#saturation ⇒ Object
Returns the percentage of saturation of the colour.
-
#saturation=(ss) ⇒ Object
Sets the percentage of saturation of the colour.
-
#to_cmyk ⇒ Object
Converts to RGB then CMYK.
- #to_greyscale ⇒ Object (also: #to_grayscale)
- #to_hsl ⇒ Object
-
#to_rgb(ignored = nil) ⇒ Object
Converting to HSL as adapted from Foley and Van-Dam from www.bobpowell.net/RGBHSB.htm.
-
#to_yiq ⇒ Object
Converts to RGB then YIQ.
Constructor Details
#initialize(h = 0, s = 0, l = 0) ⇒ HSL
Creates an HSL colour object from the standard values of degrees and percentages (e.g., 145 deg, 30%, 50%).
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# File 'lib/color/hsl.rb', line 33 def initialize(h = 0, s = 0, l = 0) @h = h / 360.0 @s = s / 100.0 @l = l / 100.0 end |
Class Method Details
Instance Method Details
#==(other) ⇒ Object
Compares the other colour to this one. The other colour will be converted to HSL before comparison, so the comparison between a HSL colour and a non-HSL colour will be approximate and based on the other colour’s #to_hsl conversion. If there is no #to_hsl conversion, this will raise an exception. This will report that two HSL values are equivalent if all component values are within Color::COLOR_TOLERANCE of each other.
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# File 'lib/color/hsl.rb', line 23 def ==(other) other = other.to_hsl other.kind_of?(Color::HSL) and ((@h - other.h).abs <= Color::COLOR_TOLERANCE) and ((@s - other.s).abs <= Color::COLOR_TOLERANCE) and ((@l - other.l).abs <= Color::COLOR_TOLERANCE) end |
#brightness ⇒ Object
Returns the luminosity (#l) of the colour.
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# File 'lib/color/hsl.rb', line 123 def brightness @l end |
#css_hsl ⇒ Object
Present the colour as an HSL HTML/CSS colour string (e.g., “hsl(180, 25%, 35%)”).
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# File 'lib/color/hsl.rb', line 60 def css_hsl "hsl(%3.2f, %3.2f%%, %3.2f%%)" % [ hue, saturation, luminosity ] end |
#css_hsla ⇒ Object
Present the colour as an HSLA (with alpha) HTML/CSS colour string (e.g., “hsla(180, 25%, 35%, 1)”).
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# File 'lib/color/hsl.rb', line 66 def css_hsla "hsla(%3.2f, %3.2f%%, %3.2f%%, %3.2f)" % [ hue, saturation, luminosity, 1 ] end |
#css_rgb ⇒ Object
Present the colour as an RGB HTML/CSS colour string (e.g., “rgb(0%, 50%, 100%)”). Note that this will perform a #to_rgb operation using the default conversion formula.
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# File 'lib/color/hsl.rb', line 47 def css_rgb to_rgb.css_rgb end |
#css_rgba ⇒ Object
Present the colour as an RGBA (with alpha) HTML/CSS colour string (e.g., “rgb(0%, 50%, 100%, 1)”). Note that this will perform a #to_rgb operation using the default conversion formula.
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# File 'lib/color/hsl.rb', line 54 def css_rgba to_rgb.css_rgba end |
#h ⇒ Object
Returns the hue of the colour in the range 0.0 .. 1.0.
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# File 'lib/color/hsl.rb', line 136 def h @h end |
#h=(hh) ⇒ Object
Sets the hue of the colour in the range 0.0 .. 1.0.
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# File 'lib/color/hsl.rb', line 150 def h=(hh) @h = Color.normalize(hh) end |
#html ⇒ Object
Present the colour as an HTML/CSS colour string.
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# File 'lib/color/hsl.rb', line 40 def html to_rgb.html end |
#hue ⇒ Object
Returns the hue of the colour in degrees.
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# File 'lib/color/hsl.rb', line 132 def hue @h * 360.0 end |
#hue=(hh) ⇒ Object
Sets the hue of the colour in degrees. Colour is perceived as a wheel, so values should be set properly even with negative degree values.
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# File 'lib/color/hsl.rb', line 141 def hue=(hh) hh = hh / 360.0 hh += 1.0 if hh < 0.0 hh -= 1.0 if hh > 1.0 @h = Color.normalize(hh) end |
#inspect ⇒ Object
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# File 'lib/color/hsl.rb', line 193 def inspect "HSL [%.2f deg, %.2f%%, %.2f%%]" % [ hue, saturation, luminosity ] end |
#l ⇒ Object
Returns the luminosity of the colour in the range 0.0 .. 1.0.
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# File 'lib/color/hsl.rb', line 176 def l @l end |
#l=(ll) ⇒ Object
Sets the luminosity of the colour in the ragne 0.0 .. 1.0.
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# File 'lib/color/hsl.rb', line 185 def l=(ll) @l = Color.normalize(ll) end |
#luminosity ⇒ Object Also known as: lightness
Returns the percentage of luminosity of the colour.
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# File 'lib/color/hsl.rb', line 171 def luminosity @l * 100.0 end |
#luminosity=(ll) ⇒ Object Also known as: lightness=
Sets the percentage of luminosity of the colour.
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# File 'lib/color/hsl.rb', line 180 def luminosity=(ll) @l = Color.normalize(ll / 100.0) end |
#mix_with(color, mix_percent = 0.5) ⇒ Object
Mix the mask colour (which will be converted to an HSL colour) with the current colour at the stated mix percentage as a decimal value.
- NOTE
-
This differs from Color::RGB#mix_with.
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# File 'lib/color/hsl.rb', line 201 def mix_with(color, mix_percent = 0.5) color = color.to_hsl _h = ((color.h - self.h) * mix_percent) + self.h _s = ((color.s - self.s) * mix_percent) + self.s _l = ((color.l - self.l) * mix_percent) + self.l self.class.from_fraction(_h, _s, _l) end |
#s ⇒ Object
Returns the saturation of the colour in the range 0.0 .. 1.0.
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# File 'lib/color/hsl.rb', line 158 def s @s end |
#s=(ss) ⇒ Object
Sets the saturation of the colour in the ragne 0.0 .. 1.0.
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# File 'lib/color/hsl.rb', line 166 def s=(ss) @s = Color.normalize(ss) end |
#saturation ⇒ Object
Returns the percentage of saturation of the colour.
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# File 'lib/color/hsl.rb', line 154 def saturation @s * 100.0 end |
#saturation=(ss) ⇒ Object
Sets the percentage of saturation of the colour.
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# File 'lib/color/hsl.rb', line 162 def saturation=(ss) @s = Color.normalize(ss / 100.0) end |
#to_cmyk ⇒ Object
Converts to RGB then CMYK.
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# File 'lib/color/hsl.rb', line 118 def to_cmyk to_rgb.to_cmyk end |
#to_greyscale ⇒ Object Also known as: to_grayscale
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# File 'lib/color/hsl.rb', line 126 def to_greyscale Color::GrayScale.from_fraction(@l) end |
#to_hsl ⇒ Object
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# File 'lib/color/hsl.rb', line 189 def to_hsl self end |
#to_rgb(ignored = nil) ⇒ Object
Converting to HSL as adapted from Foley and Van-Dam from www.bobpowell.net/RGBHSB.htm.
NOTE:
-
If the colour’s luminosity is near zero, the colour is always black.
-
If the colour’s luminosity is near one, the colour is always white.
-
If the colour’s saturation is near zero, the colour is always a shade of grey and is based only on the luminosity of the colour.
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# File 'lib/color/hsl.rb', line 79 def to_rgb(ignored = nil) return Color::RGB.new if Color.near_zero_or_less?(@l) return Color::RGB.new(0xff, 0xff, 0xff) if Color.near_one_or_more?(@l) return Color::RGB.from_fraction(@l, @l, @l) if Color.near_zero?(@s) # Is the value less than 0.5? if Color.near_zero_or_less?(@l - 0.5) tmp2 = @l * (1.0 + @s.to_f) else tmp2 = @l + @s - (@l * @s.to_f) end tmp1 = 2.0 * @l - tmp2 tmp3 = [ @h + (1.0 / 3.0), @h, @h - (1.0 / 3.0) ] rgb = tmp3.map { |hue| hue += 1.0 if Color.near_zero_or_less?(hue) hue -= 1.0 if Color.near_one_or_more?(hue) if Color.near_zero_or_less?((6.0 * hue) - 1.0) tmp1 + ((tmp2 - tmp1) * hue * 6.0) elsif Color.near_zero_or_less?((2.0 * hue) - 1.0) tmp2 elsif Color.near_zero_or_less?((3.0 * hue) - 2.0) tmp1 + (tmp2 - tmp1) * ((2 / 3.0) - hue) * 6.0 else tmp1 end } Color::RGB.from_fraction(*rgb) end |
#to_yiq ⇒ Object
Converts to RGB then YIQ.
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# File 'lib/color/hsl.rb', line 113 def to_yiq to_rgb.to_yiq end |