Convert::Color::HSV(3pm)

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

61   $h = $color->hue
62   $s = $color->saturation
63   $v = $color->value
64       Accessors for the three components of the color.
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66   $c = $color->chroma
67       Returns the derived property of "chroma", which maps the color space
68       onto a cone instead of a cylinder. This more closely measures the
69       intuitive concept of how "colorful" the color is than the saturation
70       value and is useful for distance calculations.
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72   ( $hue, $saturation, $value ) = $color->hsv
73       Returns the individual hue, saturation and value components of the
74       color value.
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76   $measure = $color->dst_hsv( $other )
77       Returns a measure of the distance between the two colors. This is the
78       Euclidean distance between the two colors as points in the chroma-
79       adjusted cone space.
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81   $measure = $color->dst_hsv_cheap( $other )
82       Returns a measure of the distance between the two colors. This is used
83       in the calculation of "dst_hsv" but since it omits the final square-
84       root and scaling it is cheaper to calculate, for use in cases where
85       only the relative values matter, such as when picking the "best match"
86       out of a set of colors. It ranges between 0 for identical colors and 4
87       for the distance between complementary pure-saturated colors.
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AUTHOR

98       Paul Evans <leonerd@leonerd.org.uk>
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102perl v5.28.0                      2018-07-14            Convert::Color::HSV(3)

NAME

SYNOPSIS

DESCRIPTION

CONSTRUCTOR

METHODS

SEE ALSO

AUTHOR