Colour class

class colourettu.Colour(my_colour='#FFF', normalized_rgb=False)

Base class for dealing with colours.

Parameters

• my_colour (str, list, or tuple) – string of hex representation of colour you are creating, or a 3 item list or tuple of the red, green, and blue channels of the colour you are creating. Default is “#FFF” (white).

• normalized_rgb (bool) – whether the values for the red, green, and blue channels are normalized (i.e. values scaled from 0 to 1) or not (i.e. values scaled from 0 to 255). Default is False.

Colours are created by calling the Colour class. Colour values can be provided via 3 or 6 digit hex notation, or providing a list or a tuple of the Red, Green, and Blue values (as integers, if normalized_rgb=False, or as floating numbers between 0 and 1 if normalized_rgb=True).

import colourettu
from colourettu import Colour

c1 = Colour()        # defaults to #FFF
c2 = Colour("#eee")  # equivalent to #EEEEEE
c3 = Colour("#456bda")
c4 = Colour([3, 56, 129])
c5 = Colour((63, 199, 233))
c6 = Colour([0.242, 0.434, 0.165], normalized_rgb=True)

The value of each channel can be pulled out:

>>> c4.red()
3
>>> c4.green()
56
>>> c4.blue()
129

You can also get the colour back as either a hex value, or a rgb tuple:

>>> c2.hex()
'#EEEEEE'
>>> c2.rgb()
(238, 238, 238)

Colours are considered equal is the values of the R, G, and B channels match.

>>> c1 == c2
False
>>> c2 == Color([238, 238, 238])
True

blue()

Returns the value of the blue channel of the Colour.

Returns

value of the blue channel of the colour

Return type

int

contrast(my_other_colour)

Calls the contrast() on the colour defined.

green()

Returns the value of the green channel of the Colour.

Returns

value of the green channel of the colour

Return type

int

hex()

Returns the HTML-style hex code for the Colour.

Returns

the colour as a HTML-sytle hex string

Return type

str

luminance()

Calls the luminance() on the colour defined.

normalized_rgb()

Returns a tuples of the normalized values of the red, green, and blue channels of the Colour.

Returns

the rgb values of the colour (with values normalized between

0.0 and 1.0)

Return type

tuple

Note

Uses the formula:

\[\begin{split}r_{norm} = \begin{cases} \frac{r_{255}}{12.92}\ \qquad &\text{if $r_{255}$ $\le$ 0.03928} \\ \left(\frac{r_{255} + 0.055}{1.055}\right)^{2.4} \quad &\text{otherwise} \end{cases}\end{split}\]

Source

red()

Returns the value of the red channel of the Colour.

Returns

value of the red channel of the colour

Return type

int

rgb()

Returns a tuples of the values of the red, green, and blue channels of the Colour.

Returns

the rgb values of the colour (with values between 0 and 255)

Return type

tuple