Class: Vissen::Output::Color

Inherits:
Object
  • Object
show all
Defined in:
lib/vissen/output/color.rb

Overview

Basic value object representing a color in the RGB color space.

Usage

The following example creates two colors, mixes them, and converts the result to an array of color component.

color_a = Color.new 0.3, 0.6, 0.2
color_b = Color.new 0.1, 0.2, 0.5

color_a.mix_with(color_b, 0.5).to_a => [0.2, 0.3, 0.35]

Direct Known Subclasses

Pixel

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(r = 0.0, g = 0.0, b = 0.0) ⇒ Color

Returns a new instance of Color.

Parameters:

  • r (Float) (defaults to: 0.0) —

    the red color value in the range (0..1).

  • g (Float) (defaults to: 0.0) —

    the green color value in the range (0..1).

  • b (Float) (defaults to: 0.0) —

    the blue color value in the range (0..1).



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# File 'lib/vissen/output/color.rb', line 23

def initialize(r = 0.0, g = 0.0, b = 0.0)
  @r = r
  @g = g
  @b = b
end

Instance Attribute Details

#b ⇒ Object

Accessors for the red, green and blue color components.



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# File 'lib/vissen/output/color.rb', line 18

def b
  @b
end

#g ⇒ Object

Accessors for the red, green and blue color components.



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# File 'lib/vissen/output/color.rb', line 18

def g
  @g
end

#r ⇒ Object

Accessors for the red, green and blue color components.



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# File 'lib/vissen/output/color.rb', line 18

def r
  @r
end

Class Method Details

.from(obj) ⇒ Color

Cast a given object to a color.

Parameters:

  • obj (Color, Array<Numeric>, Integer, #to_a) —

    the object to coerce.

Returns:

  • (Color) —

    a new color object.



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# File 'lib/vissen/output/color.rb', line 94

def from(obj)
  case obj
  when self    then obj
  when Array   then new(*obj)
  when Integer then from_integer obj
  else
    new(*obj.to_a)
  end
end

Instance Method Details

#==(other) ⇒ true, false

Color equality based on component values.

TODO: Add some small delta around what is considered the same color?

Perhaps scale to 255 and floor before comparing?

Parameters:

  • other (Object) —

    the object to check equality against.

Returns:

  • (true, false) —

    true when two colors are exactly the same.



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# File 'lib/vissen/output/color.rb', line 36

def ==(other)
  r == other.r && g == other.g && b == other.b
rescue NoMethodError
  false
end

#inspect ⇒ String

Returns a string formatted in the tradiotioal hex representation of a color: #04A4BF.

Returns:

  • (String) —

    the object string representation.



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# File 'lib/vissen/output/color.rb', line 84

def inspect
  format('#%02X%02X%02X', *to_a.map! { |v| (v * 255).round })
end

#mix_with(other, ratio) ⇒ Color

Returns a new color that is a mix between this and the other color, based on the ratio. See ‘#mix_with!` for more details.

Parameters:

  • other (Color) —

    the color to mix with

  • ratio (Float) —

    the amount (0..1) of the other color to mix in.

Returns:

  • (Color) —

    the result of the mix.



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# File 'lib/vissen/output/color.rb', line 76

def mix_with(other, ratio)
  dup.mix_with! other, ratio
end

#mix_with!(other, ratio) ⇒ self

Moves this color toword the other based on the given ratio.

ratio = 0 -> 100 % of this color ratio = 1 -> 100 % of the other color

Parameters:

  • other (Color) —

    the color to mix with

  • ratio (Float) —

    the amount (0..1) of the other color to mix in.

Returns:

  • (self) 


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# File 'lib/vissen/output/color.rb', line 60

def mix_with!(other, ratio)
  anti_ratio = (1 - ratio)

  self.r = r * anti_ratio + other.r * ratio
  self.g = g * anti_ratio + other.g * ratio
  self.b = b * anti_ratio + other.b * ratio

  self
end

#to_a ⇒ Array<Float>

Creates a new array from the color.

Returns:

  • (Array<Float>) —

    a new array containing the red, green and blue color values.



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# File 'lib/vissen/output/color.rb', line 46

def to_a
  [r, g, b]
end