Convert::Color::RGB(3pm)

1Convert::Color::RGB(3)User Contributed Perl DocumentationConvert::Color::RGB(3)
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NAME

6       "Convert::Color::RGB" - a color value represented as red/green/blue
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SYNOPSIS

9       Directly:
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11          use Convert::Color::RGB;
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13          my $red = Convert::Color::RGB->new( 1, 0, 0 );
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15          # Can also parse strings
16          my $pink = Convert::Color::RGB->new( '1,0.7,0.7' );
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18       Via Convert::Color:
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20          use Convert::Color;
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22          my $cyan = Convert::Color->new( 'rgb:0,1,1' );
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DESCRIPTION

25       Objects in this class represent a color in RGB space, as a set of three
26       floating-point values in the range 0 to 1.
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28       For representations using 8- or 16-bit integers, see
29       Convert::Color::RGB8 and Convert::Color::RGB16.
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CONSTRUCTOR

32   new
33          $color = Convert::Color::RGB->new( $red, $green, $blue )
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35       Returns a new object to represent the set of values given. These values
36       should be floating-point numbers between 0 and 1. Values outside of
37       this range will be clamped.
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39          $color = Convert::Color::RGB->new( $string )
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41       Parses $string for values, and construct a new object similar to the
42       above three-argument form. The string should be in the form
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44          red,green,blue
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46       containing the three floating-point values in decimal notation.
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METHODS

49   red
50          $r = $color->red
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52   green
53          $g = $color->green
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55   blue
56          $b = $color->blue
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58       Accessors for the three components of the color.
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60   rgb
61          ( $red, $green, $blue ) = $color->rgb
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63       Returns the individual red, green and blue color components of the
64       color value.
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66   alpha_blend
67          $mix = $color->alpha_blend( $other, [ $alpha ] )
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69       Return a new color which is a blended combination of the two passed
70       into it.  The optional $alpha parameter defines the mix ratio between
71       the two colors, defaulting to 0.5 if not defined. Values closer to 0
72       will blend more of $color, closer to 1 will blend more of $other.
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74   dst_rgb
75          $measure = $color->dst_rgb( $other )
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77       Return a measure of the distance between the two colors. This is the
78       unweighted Euclidean distance of the three color components. Two
79       identical colors will have a measure of 0, pure black and pure white
80       have a distance of 1, and all others will lie somewhere inbetween.
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82   dst_rgb_cheap
83          $measure = $color->dst_rgb_cheap( $other )
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85       Return a measure of the distance between the two colors. This is the
86       sum of the squares of the differences of each of the color components.
87       This is part of the value used to calculate "dst_rgb", but since it
88       involves no square root it will be cheaper to calculate, for use in
89       cases where only the relative values matter, such as when picking the
90       "best match" out of a set of colors.  It ranges between 0 for identical
91       colours and 3 for the distance between pure black and pure white.
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EXAMPLES

94   Generating Gradients
95       The "alpha_blend" method can be used to generate a smooth gradient
96       between two colours.
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98          use Convert::Color;
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100          my $blue = Convert::Color->new("vga:blue");
101          my $cyan = Convert::Color->new("vga:cyan");
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103          say $blue->alpha_blend( $cyan, $_/10 )->as_rgb8->hex for 0 .. 10
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AUTHOR

115       Paul Evans <leonerd@leonerd.org.uk>
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119perl v5.34.1                      2022-05-10            Convert::Color::RGB(3)