Color Picker Library

color_picker

CircuitPython helper library to select color using a color wheel in resistive displays using DisplayIO library

  • Author(s): Jose David M.

Implementation Notes

class color_picker.color_picker.ColorPicker(*args: Any, **kwargs: Any)

A widget to be used to select colors from a heel.

Parameters:

  • filename (str) – name of the bitmap file to be used as a ColorPicker

  • x (int) – x position of the color picker origin

  • y (int) – y position of the color picker origin

  • imagesize (int) – size of the bitmap file. The bitmap colorwheels are squares.

Quickstart: Importing and using the Color Picker

Here is one way of importing the ColorPicker class so you can use:

from adafruit_displayio_color_picker import color_picker

Now you can create an Slider at pixel position x=20, y=30 using:

my_colorpicker=color_picker.ColorPicker(x=20, y=30)

Once you setup your display, you can now add my_colorpicker to your display using:

display.show(my_colorpicker) # add the group to the display

If you want to have multiple display elements, you can create a group and then append the slider and the other elements to the group. Then, you can add the full group to the display as in this example:

my_colorpicker= ColorPicker(20, 30)
my_group = displayio.Group(max_size=2) # make a group that can hold 2 items
my_group.append(my_colorpicker) # Add my_colorpicker to the group

#
# Append other display elements to the group
#

display.show(my_group) # add the group to the display

Final Notes

Depending on the screen results may vary. Resolution of the bitmap will no be as seen in a PC. Sensitivity of the screen could also affect the behaviour of the library.

The Color Picker Widget

Example of the color picker widget.

Example of the color picker. representation will vary according to screen used.

contains(touch_point)

Checks if the ColorPicker was touched. Returns True if the touch_point is within the ColorPicker’s touch_boundary.

Parameters:

touch_point (Tuple[x,y]) – x,y location of the screen, converted to local coordinates.

Returns:

Boolean

when_selected(touch_point, screen_height)

Response function when ColorPicker is selected. When selected, the ColorPicker will give the color corresponding with the position

Parameters:

  • touch_point – x,y location of the screen, in absolute display coordinates.

  • screen_height (int) – screen height

Returns:

Color

wheel_maker

Save a displayio.Bitmap (and associated displayio.Palette) in a BMP file. This script is adapted in the works from Dave Astels on the adafruit_bitmapsaver and the works of Jackson Glabbard https://jg.gg/2012/05/28/generating-a-color-picker-style-color-wheel-in-python/ https://github.com/jacksongabbard/Python-Color-Gamut-Generator/blob/master/color-wheel-generator.py and Kevin Matocha on the switch_round for the _color_to_tuple function

  • Author(s): Dave Astels, Jackson Glabbard, Kevin Matocha, Jose David M.

Implementation Notes

color_picker.wheel_maker.color_to_tuple(value)

Converts a color from a 24-bit integer to a tuple. :param value: RGB LED desired value - can be a RGB tuple or a 24-bit integer.

color_picker.wheel_maker.make_color(base, adj, ratio, shade)

Go through each bit of the colors adjusting blue with blue, red with red, green with green, etc.

color_picker.wheel_maker.make_wheel(image_name, img_size, bg_color=0)
Parameters:

  • image_name – Name of the ouput bitmap image

  • img_size – size of the bitmap image in pixels height=width

  • bg_color – color of the background in 24 bit format. Defaults 0x000000

Returns:

color

Quickstart: Importing and using the make_wheel

Here is one way of importing the make_wheel module so you can use:

from adafruit_displayio_color_picker import wheel_maker

Now you can create a wheel of 200 pixels with a black background using:

make_wheel("wheel200.bmp", 200 , 0x000000)