Color Handling

Introduction

The default color configuration comes with one RGB sequence as a default in the configuration file. You can import color sequences from a YAML definition file as well, or you can define your own in code of course. This section describes how.

Get more details on crafting your YAML file in this tutorial section: YAML Color Definitions.

Color Objects

Colorwheels introduces 2 objects to handle color definitions: ColorItem, WheelItem for one specific color generator. The base class - Colorwheels - handles multiple generator defintions, and related operations: loading, swapping color schemes etc.

• ColorItem : this is a dataclass which captures RGB information, and handles color conversions. You can use it stand-alone, or you can use it in lists of colors. One of those special color lists is a ‘wheel_item’, described below.

• WheelItem : A wheel Item is a dataclass, which handles one named collection of colors. It contains a list of ColorItem objects and gives them a label. This is the base of one color definition.

YAML Definition

The easiest way to define colors is the code your own YAML file. We have a whole section dedicated to YAML, read more in YAML Color Definitions. You can also find an example color definition file in the examples directory.

Colors in code

You may want to add a color definitions to the pool of available colors (which is managed by ColorwheelsConfig). As soon as the color definition you create is added, it will be available to all Colorwheels instances.

A color definition is basically a list of colors (defined by the ColorItem dataclass) with a name attached. This is bundled in the WheelItem dataclass.

So, adding your own RGB sequence using code could look like this:

# mywheels.py
#
# Colorwheel Generator Example 4

from typing import List
import colorwheels

def my_rgb():
    """Create a list of colors (rgb)"""

    color_list = list()
    color_list.append(colorwheels.ColorItem(red=255, green=0, blue=0))
    color_list.append(colorwheels.ColorItem(red=0, green=255, blue=0))
    color_list.append(colorwheels.ColorItem(red=0, green=0, blue=255))

    return color_list

wheels = colorwheels.Colorwheels()
# add my new list named 'myrgb' to common configurations ->
# can be used by any other instance of Colorwheels
wheels.wheel_configurations.add_wheel_item(colorwheels.WheelItem("myrgb", my_rgb()))

Base Colors

Your application may depend on some base colors, not necessarily in a / any sequence. Colorwheels has you covered: you can invoke add_base_colors in ColorwheelsConfig and these colors will be available to you. The idea is, that the generator can serve only one color, again and again. In any format.

The add_base_colors method adds the following colors to your configuration file: ‘red’, ‘green’, ‘blue’, ‘cyan’, ‘magenta’, ‘yellow’, ‘black’, and ‘white’.

We use this feature not only for static basic colors, but also in solutions, where a background and foreground colorwheel are needed. For the foreground, we use a rotating Colorwheel based on the aesthetics of the solution, but for the background we start we a static color, say black. Now if we want to rotate both the foreground and background, we simply activate a different background. Neat hallucinogenous effects can be achieved, on the same color engine.

Base colors can be enforced by using the add_base_colors flag in load_wheels of ColorwheelsConfig, or when creating a new Colorwheels instance. In both cases, the default is set to True, so you’ll probably end-up having them in your color collection.

Tip: you may want to over-ride a base color setting for one reason or another. For example, if you want your specific flavor of ‘red’ instead of the default ‘(255,0,0)’, simply define it in your YAML configuration file; add_base_colors adds colors by name, only if they don’t exist yet.