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

6       "Convert::Color::HSV" - a color value represented as
7       hue/saturation/value
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SYNOPSIS

10       Directly:
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12          use Convert::Color::HSV;
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14          my $red = Convert::Color::HSV->new( 0, 1, 1 );
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16          # Can also parse strings
17          my $pink = Convert::Color::HSV->new( '0,0.7,1' );
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19       Via Convert::Color:
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21          use Convert::Color;
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23          my $cyan = Convert::Color->new( 'hsv:300,1,1' );
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DESCRIPTION

26       Objects in this class represent a color in HSV space, as a set of three
27       floating-point values. Hue is stored as a value in degrees, in the
28       range 0 to 360 (exclusive). Saturation and value are in the range 0 to
29       1.
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31       This color space may be considered as a cylinder, of height and radius
32       1. Hue represents the position of the color as the angle around the
33       axis, the saturation the distance from the axis, and the value the
34       height above the base. In this shape, the entire base of the cylinder
35       is pure black, the axis through the centre represents the range of
36       greys, and the circumference of the top of the cylinder contains the
37       pure-saturated color wheel, with a pure white point at its centre.
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39       Because the entire bottom surface of this cylinder contains black, a
40       closely-related color space can be created by reshaping the cylinder
41       into a cone by contracting the base of the cylinder into a point. The
42       radius from the axis is called the chroma (though this is a different
43       definition of "chroma" than that used by CIE).
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CONSTRUCTOR

46   new
47          $color = Convert::Color::HSV->new( $hue, $saturation, $value )
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49       Returns a new object to represent the set of values given. The hue
50       should be in the range 0 to 360 (exclusive), and saturation and value
51       should be between 0 and 1. Values outside of these ranges will be
52       clamped.
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54          $color = Convert::Color::HSV->new( $string )
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56       Parses $string for values, and construct a new object similar to the
57       above three-argument form. The string should be in the form
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59          hue,saturation,value
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61       containing the three floating-point values in decimal notation.
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METHODS

64   hue
65          $h = $color->hue
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67   saturation
68          $s = $color->saturation
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70   value
71          $v = $color->value
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73       Accessors for the three components of the color.
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75   chroma
76          $c = $color->chroma
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78       Returns the derived property of "chroma", which maps the color space
79       onto a cone instead of a cylinder. This more closely measures the
80       intuitive concept of how "colorful" the color is than the saturation
81       value and is useful for distance calculations.
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83   hsv
84          ( $hue, $saturation, $value ) = $color->hsv
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86       Returns the individual hue, saturation and value components of the
87       color value.
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89   dst_hsv
90          $measure = $color->dst_hsv( $other )
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92       Returns a measure of the distance between the two colors. This is the
93       Euclidean distance between the two colors as points in the chroma-
94       adjusted cone space.
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96   dst_hsv_cheap
97          $measure = $color->dst_hsv_cheap( $other )
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99       Returns a measure of the distance between the two colors. This is used
100       in the calculation of "dst_hsv" but since it omits the final square-
101       root and scaling it is cheaper to calculate, for use in cases where
102       only the relative values matter, such as when picking the "best match"
103       out of a set of colors. It ranges between 0 for identical colors and 4
104       for the distance between complementary pure-saturated colors.
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SEE ALSO

107       •   Convert::Color - color space conversions
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109       •   Convert::Color::RGB - a color value represented as red/green/blue
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111       •   <http://en.wikipedia.org/wiki/HSL_and_HSV> - HSL and HSV on
112           Wikipedia
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AUTHOR

115       Paul Evans <leonerd@leonerd.org.uk>
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119perl v5.36.0                      2023-04-24            Convert::Color::HSV(3)
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