nodemcu-firmware/docs/modules/color-utils.md

color utils Module

Since	Origin / Contributor	Maintainer	Source
2017-12-30	Konrad Huebner	Konrad Huebner	color_utils.c

This module provides basic color transformations useful for color LEDs.

color_utils.hsv2grb()

Convert HSV color to GRB color.

Syntax

color_utils.hsv2grb(hue, saturation, value)

Parameters

• hue is the hue value, between 0 and 360
• saturation is the saturation value, between 0 and 255
• value is the value value, between 0 and 255

Returns

green, red, blue as values between 0 and 255

color_utils.hsv2grbw()

Convert HSV color to GRB color and explicitly return a white value. This can be useful for RGB+W LED strips. The white value is simply calculated as min(g, r, b) and then removed from the colors. This does NOT take into account if the white chip used later creates an appropriate color.

Syntax

color_utils.hsv2grbw(hue, saturation, value)

Parameters

• hue is the hue value, between 0 and 360
• saturation is the saturation value, between 0 and 255
• value is the value value, between 0 and 255

Returns

green, red, blue, white as values between 0 and 255

color_utils.grb2hsv()

Convert GRB color to HSV color.

Syntax

color_utils.grb2hsv(green, red, blue)

Parameters

• green is the green value, between 0 and 255
• red is the red value, between 0 and 255
• blue is the blue value, between 0 and 255

Returns

hue, saturation, value as values between 0 and 360, respective 0 and 255

color_utils.colorWheel()

The color wheel function makes use of the HSV color space and calculates colors based on the color circle. The colors are created with full saturation and value. This function is a convenience function of the hsv2grb function and can be used to create rainbow colors.

Syntax

color_utils.colorWheel(angle)

Parameters

• angle is the angle on the color circle, between 0 and 359

Returns

green, red, blue as values between 0 and 255