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# Copyright (c) 2012 - 2017, Anaconda, Inc. All rights reserved.
#
# Powered by the Bokeh Development Team.
#
# The full license is in the file LICENSE.txt, distributed with this software.
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''' Provide a class to represent colors with HSL (Hue, Saturation, Value).
'''
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# Boilerplate
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from __future__ import absolute_import, division, print_function, unicode_literals
import logging
log = logging.getLogger(__name__)
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# Imports
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# Standard library imports
import colorsys
# External imports
# Bokeh imports
from .color import Color
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# Globals and constants
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# General API
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[docs]class HSL(Color):
''' Represent colors by specifying their Hue, Saturation, and Value.
Alpha values may also optionally be provided. Otherwise, alpha values
default to 1.
'''
[docs] def __init__(self, h, s, l, a=1.0):
'''
Args:
h (int) :
The Hue, in [0, 255]
h (int) :
The Saturation, in [0, 1]
h (int) :
The Value, in [0, 1]
a (float, optional) :
An alpha value for this color in [0, 1] (default: 1.0)
'''
self.h = h
self.s = s
self.l = l
self.a = a
[docs] def copy(self):
''' Return a copy of this color value.
Returns:
HSL
'''
return HSL(self.h, self.s, self.l, self.a)
[docs] @classmethod
def from_hsl(cls, value):
''' Copy an HSL color from another HSL color value.
Args:
value (HSL) :
The HSL color to copy.
Returns:
HSL
'''
return value.copy()
[docs] @classmethod
def from_rgb(cls, value):
''' Create an HSL color from an RGB color value.
Args:
value (:class:`~bokeh.colors.rgb.RGB`) :
The RGB color to convert.
Returns:
HSL
'''
return value.to_hsl()
[docs] def to_css(self):
''' Generate the CSS representation of this HSL color.
Returns:
str, ``"hsl(...)"`` or ``"hsla(...)"``
'''
if self.a == 1.0:
return "hsl(%d, %s%%, %s%%)" % (self.h, self.s*100, self.l*100)
else:
return "hsla(%d, %s%%, %s%%, %s)" % (self.h, self.s*100, self.l*100, self.a)
[docs] def to_hsl(self):
''' Return a HSL copy for this HSL color.
Returns:
HSL
'''
return self.copy()
[docs] def to_rgb(self):
''' Return a corresponding :class:`~bokeh.colors.rgb.RGB` color for
this HSL color.
Returns:
HSL
'''
from .rgb import RGB # prevent circular import
r, g, b = colorsys.hls_to_rgb(float(self.h)/360, self.l, self.s)
return RGB(round(r*255), round(g*255), round(b*255), self.a)
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# Dev API
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# Private API
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# Code
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