1Graphics::ColorNames(3)User Contributed Perl DocumentatioGnraphics::ColorNames(3)
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6 Graphics::ColorNames - defines RGB values for common color names
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9 version v3.5.0
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12 use Graphics::ColorNames;
13 use Graphics::ColorNames::WWW;
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15 $pal = Graphics::ColorNames->new( qw[ X WWW ] );
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17 $rgb = $pal->hex('green'); # returns '00ff00'
18 $rgb = $pal->hex('green', '0x'); # returns '0x00ff00'
19 $rgb = $pal->hex('green', '#'); # returns '#00ff00'
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21 $rgb = $pal->rgb('green'); # returns '0,255,0'
22 @rgb = $pal->rgb('green'); # returns (0, 255, 0)
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25 This module provides a common interface for obtaining the RGB values of
26 colors by standard names. The intention is to (1) provide a common
27 module that authors can use with other modules to specify colors by
28 name; and (2) free module authors from having to "re-invent the wheel"
29 whenever they decide to give the users the option of specifying a color
30 by name rather than RGB value.
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33 "new"
34 The constructor is as follows:
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36 my $pal = Graphics::ColorNames->new( @schemes );
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38 where @schemes is an array of color schemes (palettes, dictionaries).
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40 A valid color scheme may be the name of a color scheme (such as "X" or
41 a full module name such as "Graphics::ColorNames::X"), a reference to a
42 color scheme hash or subroutine, or to the path or open filehandle for
43 a rgb.txt file.
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45 If none are specified, it uses the default "X" color scheme, which
46 corresponds to the X-Windows rgb.txt colors. For most purposes, this
47 is good enough. Since v3.2.0, it was updated to use the 2014-07-06
48 colors, so includes the standard CSS colors as well.
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50 Other color schemes are available on CPAN, e.g.
51 Graphics::ColorNames::WWW.
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53 Since version 2.1002, Color::Library dictionaries can be used as well:
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55 my $pal = Graphics::ColorNames->new( 'Color::Library::Dictionary::HTML' );
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57 "rgb"
58 @rgb = $pal->rgb($name);
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60 $rgb = $pal->rgb($name, $separator);
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62 If called in a list context, returns a triplet.
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64 If called in a scalar context, returns a string separated by an
65 optional separator (which defauls to a comma). For example,
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67 @rgb = $pal->rgb('blue'); # returns (0, 0, 255)
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69 $rgb = $pal->rgb('blue', ','); # returns "0,0,255"
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71 Unknown color names return empty lists or strings, depending on the
72 context.
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74 Color names are case insensitive, and spaces or punctuation are
75 ignored. So "Alice Blue" returns the same value as "aliceblue", "ALICE-
76 BLUE" and "a*lICEbl-ue". (If you are using color names based on user
77 input, you should add additional validation of the color names.)
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79 The value returned is in the six-digit hexidecimal format used in HTML
80 and CSS (without the initial '#'). To convert it to separate red,
81 green, and blue values (between 0 and 255), use the "hex2tuple"
82 function.
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84 You may also specify an absolute filename as a color scheme, if the
85 file is in the same format as the standard rgb.txt file.
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87 "hex"
88 $hex = $pal->hex($name, $prefix);
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90 Returns a 6-digit hexidecimal RGB code for the color. If an optional
91 prefix is specified, it will prefix the code with that string. For
92 example,
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94 $hex = $pal->hex('blue', '#'); # returns "#0000ff"
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96 If the color does not exist, it will return an empty string.
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98 A hexidecimal RGB value in the form of "#RRGGBB", "0xRRGGBB" or
99 "RRGGBB" will return itself:
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101 $color = $pal->hex('#123abc'); # returns '123abc'
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103 autoloaded color name methods
104 Autoloaded color name methods were removed in v3.4.0.
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106 "load_scheme"
107 $pal->load_scheme( $scheme );
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109 This dynamically loads a color scheme, which can be either a hash
110 reference or code reference.
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113 "all_schemes"
114 my @schemes = all_schemes();
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116 Returns a list of all available color schemes installed on the machine
117 in the Graphics::ColorNames namespace.
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119 The order has no significance.
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121 "hex2tuple"
122 Converts a hexidecimal string to a tuple.
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124 "tuple2hex"
125 Converts a tuple to a hexidecimal string.
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128 The standard interface (prior to version 0.40) was through a tied hash:
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130 tie %pal, 'Graphics::ColorNames', qw[ X WWW ];
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132 This interface is deprecated, and will be moved to a separate module in
133 the future.
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136 You can add naming scheme files by creating a Perl module is the name
137 "Graphics::ColorNames::SCHEMENAME" which has a subroutine named
138 "NamesRgbTable" that returns a hash of color names and RGB values.
139 (Schemes with a different base namespace will require the fill
140 namespace to be given.)
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142 The color names must be in all lower-case, and the RGB values must be
143 24-bit numbers containing the red, green, and blue values in most-
144 significant to least- significant byte order.
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146 An example naming schema is below:
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148 package Graphics::ColorNames::Metallic;
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150 sub NamesRgbTable() {
151 use integer;
152 return {
153 copper => 0xb87333,
154 gold => 0xcd7f32,
155 silver => 0xe6e8fa,
156 };
157 }
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159 You would use the above schema as follows:
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161 tie %colors, 'Graphics::ColorNames', 'Metallic';
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163 The behavior of specifying multiple keys with the same name is
164 undefined as to which one takes precedence.
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166 As of version 2.10, case, spaces and punctuation are ignored in color
167 names. So a name like "Willy's Favorite Shade-of-Blue" is treated the
168 same as "willysfavoroteshadeofblue". (If your scheme does not include
169 duplicate entrieswith spaces and punctuation, then the minimum version
170 of Graphics::ColorNames should be 2.10 in your requirements.)
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172 An example of an additional module is the Graphics::ColorNames::Mozilla
173 module.
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175 Since version 1.03, "NamesRgbTable" may also return a code reference:
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177 package Graphics::ColorNames::Orange;
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179 sub NamesRgbTable() {
180 return sub {
181 my $name = shift;
182 return 0xffa500;
183 };
184 }
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186 See Graphics::ColorNames::GrayScale for an example.
187
189 The following changes are planned in the future:
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191 · The tied interface will be removed, but implemented in a separate
192 module for users that wish to use it.
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194 · The namespace for color schemes will be moved to the
195 "Graphics::ColorNames::Schemes" but options will be added to use
196 the existing scheme.
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198 This will allow modules to be named like
199 "Graphics::ColorNames::Tied" without being confused for color
200 schemes.
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202 · This module will be rewritten to be a Moo-based class.
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205 Color::Library provides an extensive library of color schemes. A
206 notable difference is that it supports more complex schemes which
207 contain additional information about individual colors and map multiple
208 colors to a single name.
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210 Color::Rgb has a similar function to this module, but parses an rgb.txt
211 file.
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213 Graphics::ColorObject can convert between RGB and other color space
214 types.
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216 Graphics::ColorUtils can also convert betweeb RGB and other color space
217 types, and supports RGB from names in various color schemes.
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219 Acme::AutoColor provides subroutines corresponding to color names.
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222 The development version is on github at
223 <https://github.com/robrwo/Graphics-ColorNames> and may be cloned from
224 <git://github.com/robrwo/Graphics-ColorNames.git>
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226 The SourceForge project for this module at
227 <http://sourceforge.net/projects/colornames/> is no longer maintained.
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230 Please report any bugs or feature requests on the bugtracker website
231 <https://rt.cpan.org/Public/Dist/Display.html?Name=Graphics-ColorNames>
232 or by email to bug-Graphics-ColorNames@rt.cpan.org <mailto:bug-
233 Graphics-ColorNames@rt.cpan.org>.
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235 When submitting a bug or request, please include a test-file or a patch
236 to an existing test-file that illustrates the bug or desired feature.
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239 Robert Rothenberg <rrwo@cpan.org>
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242 · Alan D. Salewski <alans@cji.com>
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244 · Steve Pomeroy <xavier@cpan.org>
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246 · "chemboy" <chemboy@perlmonk.org>
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248 · Magnus Cedergren <magnus@mbox604.swipnet.se>
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250 · Gary Vollink <gary@vollink.com>
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252 · Claus Färber <cfaerber@cpan.org>
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254 · Andreas J. König <andk@cpan.org>
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256 · Slaven Rezić <slaven@rezic.de>
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259 This software is Copyright (c) 2001-2019 by Robert Rothenberg.
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261 This is free software, licensed under:
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263 The Artistic License 2.0 (GPL Compatible)
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267perl v5.32.0 2020-07-28 Graphics::ColorNames(3)