Class: Colors

Inherits:
Object
  • Object
show all
Defined in:
lib/kang/colors.rb

Overview

color.rb - Generate randon color sets that are distinguishable

Copyright © 2014 Tony Doan <[email protected]>. All rights reserved.

This software is licensed as described in the file COPYING, which you should have received as part of this distribution. The terms are also available at github.com/tdoan/kang/tree/master/COPYING. If newer versions of this license are posted there, you may use a newer version instead, at your option.

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(initial_size = nil, options = {}) ⇒ Colors

Returns a new instance of Colors.



16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
 
# File 'lib/kang/colors.rb', line 16

def initialize(initial_size=nil, options={})
  valid_options = [:saturation,:value,:starting_hue,:range]
  default_options = {saturation:0.3, value:0.8, :starting_hue=>rand, :range=>256}
  options.keys.each do |k|
    raise ArgumentError, "Unknown option: #{k}" unless valid_options.include? k
  end
  default_options.merge!(options)
  [:saturation, :value, :starting_hue].each do |k|
    raise ArgumentError, "The option \"#{k.to_s}\" must be between 0 and 1" if((default_options[k] > 1) or (default_options[k] < 0))
  end
  @golden_ratio_conjugate = 0.618033988749895
  @h = default_options[:starting_hue]
  @saturation = default_options[:saturation]
  @value = default_options[:value]
  @colors = []
  @range = default_options[:range]
  unless initial_size.nil?
    initial_size.times do
      self.next
    end
  end
end

Class Method Details

.to_hex(rgb) ⇒ Object 



39
40
41
 
# File 'lib/kang/colors.rb', line 39

def self.to_hex(rgb)
  rgb.collect{|n| n.to_s(16).upcase}.join
end

Instance Method Details

#[](i) ⇒ Object 



62
63
64
65
66
67
68
69
70
 
# File 'lib/kang/colors.rb', line 62

def [](i)
  if @colors.size-1 < i
    diff  = i - @colors.size + 1
    (diff).times do
      self.next
    end
  end
  @colors[i]
end

#each(&block) ⇒ Object 



58
59
60
 
# File 'lib/kang/colors.rb', line 58

def each(&block)
  @colors.each(&block)
end

#hsv_to_rgb(h, s, v) ⇒ Object 



43
44
45
46
47
48
49
50
51
52
53
54
55
56
 
# File 'lib/kang/colors.rb', line 43

def hsv_to_rgb(h, s, v)
  h_i = (h*6).to_i
  f = h*6 - h_i
  p = v * (1 - s)
  q = v * (1 - f*s)
  t = v * (1 - (1 - f) * s)
  r, g, b = v, t, p if h_i==0
  r, g, b = q, v, p if h_i==1
  r, g, b = p, v, t if h_i==2
  r, g, b = p, q, v if h_i==3
  r, g, b = t, p, v if h_i==4
  r, g, b = v, p, q if h_i==5
  [(r*@range).to_i, (g*@range).to_i, (b*@range).to_i]
end

#next ⇒ Object 



72
73
74
75
76
77
78
 
# File 'lib/kang/colors.rb', line 72

def next
  @h += @golden_ratio_conjugate
  @h %= 1
  c = hsv_to_rgb(@h, @saturation, @value)
  @colors << c
  c
end