Source code for bokeh.colors.rgb
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# Copyright (c) 2012 - 2022, Anaconda, Inc., and Bokeh Contributors.
# All rights reserved.
#
# The full license is in the file LICENSE.txt, distributed with this software.
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'''
'''
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# Boilerplate
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from __future__ import annotations
import logging # isort:skip
log = logging.getLogger(__name__)
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# Imports
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# Standard library imports
import colorsys
from math import sqrt
from typing import TYPE_CHECKING
# Bokeh imports
from .color import Color
if TYPE_CHECKING:
from .hsl import HSL
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# Globals and constants
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__all__ = (
'RGB',
)
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# General API
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[docs]class RGB(Color):
''' Represent colors by specifying their Red, Green, and Blue channels.
Alpha values may also optionally be provided. Otherwise, alpha values
default to 1.
'''
[docs] def __init__(self, r: int, g: int, b: int, a: float = 1.0) -> None:
'''
Args:
r (int) :
The value for the red channel in [0, 255]
g (int) :
The value for the green channel in [0, 255]
b (int) :
The value for the blue channel in [0, 255]
a (float, optional) :
An alpha value for this color in [0, 1] (default: 1.0)
'''
self.r = r
self.g = g
self.b = b
self.a = a
[docs] def copy(self) -> RGB:
''' Return a copy of this color value.
Returns:
:class:`~bokeh.colors.rgb.RGB`
'''
return RGB(self.r, self.g, self.b, self.a)
[docs] @classmethod
def from_hsl(cls, value: HSL) -> RGB:
''' Create an RGB color from an HSL color value.
Args:
value (HSL) :
The HSL color to convert.
Returns:
:class:`~bokeh.colors.rgb.RGB`
'''
return value.to_rgb()
[docs] @classmethod
def from_rgb(cls, value: RGB) -> RGB:
''' Copy an RGB color from another RGB color value.
Args:
value (:class:`~bokeh.colors.rgb.RGB`) :
The RGB color to copy.
Returns:
:class:`~bokeh.colors.rgb.RGB`
'''
return value.copy()
[docs] def to_css(self) -> str:
''' Generate the CSS representation of this RGB color.
Returns:
str, ``"rgb(...)"`` or ``"rgba(...)"``
'''
if self.a == 1.0:
return f"rgb({self.r}, {self.g}, {self.b})"
else:
return f"rgba({self.r}, {self.g}, {self.b}, {self.a})"
[docs] def to_hex(self) -> str:
''' Return a hex color string for this RGB color.
Any alpha value on this color is discarded, only hex color strings for
the RGB components are returned.
Returns:
str, ``"#RRGGBB"``
'''
return "#%02X%02X%02X" % (self.r, self.g, self.b)
[docs] def to_hsl(self) -> HSL:
''' Return a corresponding HSL color for this RGB color.
Returns:
:class:`~bokeh.colors.hsl.HSL`
'''
from .hsl import HSL # prevent circular import
h, l, s = colorsys.rgb_to_hls(float(self.r)/255, float(self.g)/255, float(self.b)/255)
return HSL(round(h*360), s, l, self.a)
[docs] def to_rgb(self) -> RGB:
''' Return a RGB copy for this RGB color.
Returns:
:class:`~bokeh.colors.rgb.RGB`
'''
return self.copy()
@property
def brightness(self) -> float:
""" Perceived brightness of a color in [0, 1] range. """
# http://alienryderflex.com/hsp.html
r, g, b = self.r, self.g, self.b
return sqrt(0.299*r**2 + 0.587*g**2 + 0.114*b**2)/255
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# Dev API
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# Private API
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# Code
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