# SPDX-FileCopyrightText: 2017 PaintYourDragon for Adafruit Industries
#
# SPDX-License-Identifier: MIT
"""
`adafruit_fancyled.adafruit_fancyled`
====================================================
FancyLED is a CircuitPython library to assist in creating buttery smooth LED animation.
It's loosely inspired by the FastLED library for Arduino, and in fact we have a "helper"
library using similar function names to assist with porting of existing Arduino FastLED
projects to CircuitPython.
* Author(s): PaintYourDragon
"""
# imports
__version__ = "0.0.0-auto.0"
__repo__ = "https://github.com/Adafruit/Adafruit_CircuitPython_FancyLED.git"
from math import floor
# FancyLED provides color- and palette-related utilities for LED projects,
# offering a buttery smooth look instead of the usual 8-bit-like "blip blip"
# effects often seen with LEDs. It's loosely inspired by, but NOT a drop-in
# replacement for, the FastLED library for Arduino.
[docs]class CRGB:
"""Color stored in Red, Green, Blue color space.
One of two ways: separate red, gren, blue values (either as integers
(0 to 255 range) or floats (0.0 to 1.0 range), either type is
'clamped' to valid range and stored internally in the normalized
(float) format), OR can accept a CHSV color as input, which will be
converted and stored in RGB format.
Following statements are equivalent - all return red:
.. code-block:: python
c = CRGB(255, 0, 0)
c = CRGB(1.0, 0.0, 0.0)
c = CRGB(CHSV(0.0, 1.0, 1.0))
"""
def __init__(self, red, green=0.0, blue=0.0):
# pylint: disable=too-many-branches
if isinstance(red, CHSV):
# If first/only argument is a CHSV type, perform HSV to RGB
# conversion.
hsv = red # 'red' is CHSV, this is just more readable
hue = hsv.hue * 6.0 # Hue circle = 0.0 to 6.0
sxt = floor(hue) # Sextant index is next-lower integer of hue
frac = hue - sxt # Fraction-within-sextant is 0.0 to <1.0
sxt = int(sxt) % 6 # mod6 the sextant so it's always 0 to 5
if sxt == 0: # Red to <yellow
r, g, b = 1.0, frac, 0.0
elif sxt == 1: # Yellow to <green
r, g, b = 1.0 - frac, 1.0, 0.0
elif sxt == 2: # Green to <cyan
r, g, b = 0.0, 1.0, frac
elif sxt == 3: # Cyan to <blue
r, g, b = 0.0, 1.0 - frac, 1.0
elif sxt == 4: # Blue to <magenta
r, g, b = frac, 0.0, 1.0
else: # Magenta to <red
r, g, b = 1.0, 0.0, 1.0 - frac
invsat = 1.0 - hsv.saturation # Inverse-of-saturation
self.red = ((r * hsv.saturation) + invsat) * hsv.value
self.green = ((g * hsv.saturation) + invsat) * hsv.value
self.blue = ((b * hsv.saturation) + invsat) * hsv.value
else:
# Red, green, blue arguments (normalized floats OR integers)
# TODO(tannewt): Factor this out into a helper function
if isinstance(red, float):
self.red = clamp(red, 0.0, 1.0)
else:
self.red = normalize(red)
if isinstance(green, float):
self.green = clamp(green, 0.0, 1.0)
else:
self.green = normalize(green)
if isinstance(blue, float):
self.blue = clamp(blue, 0.0, 1.0)
else:
self.blue = normalize(blue)
def __repr__(self): # pylint: disable=invalid-repr-returned
return (self.red, self.green, self.blue)
def __str__(self):
return "(%s, %s, %s)" % (self.red, self.green, self.blue)
def __len__(self):
"""Retrieve total number of color-parts available."""
return 3
def __getitem__(self, key):
"""Retrieve red, green or blue value as iterable."""
if key == 0:
return self.red
if key == 1:
return self.green
if key == 2:
return self.blue
raise IndexError
[docs] def pack(self):
"""'Pack' a `CRGB` color into a 24-bit RGB integer.
:returns: 24-bit integer a la ``0x00RRGGBB``.
"""
return (
(denormalize(self.red) << 16)
| (denormalize(self.green) << 8)
| (denormalize(self.blue))
)
[docs]class CHSV:
"""Color stored in Hue, Saturation, Value color space.
Accepts hue as float (any range) or integer (0-256 -> 0.0-1.0) with
no clamping performed (hue can 'wrap around'), saturation and value
as float (0.0 to 1.0) or integer (0 to 255), both are clamped and
stored internally in the normalized (float) format. Latter two are
optional, can pass juse hue and saturation/value will default to 1.0.
Unlike `CRGB` (which can take a `CHSV` as input), there's currently
no equivalent RGB-to-HSV conversion, mostly because it's a bit like
trying to reverse a hash...there may be multiple HSV solutions for a
given RGB input.
This might be OK as long as conversion precedence is documented,
but otherwise (and maybe still) could cause confusion as certain
HSV->RGB->HSV translations won't have the same input and output.
"""
def __init__(self, h, s=1.0, v=1.0):
if isinstance(h, float):
self.hue = h # Don't clamp! Hue can wrap around forever.
else:
self.hue = float(h) / 256.0
if isinstance(s, float):
self.saturation = clamp(s, 0.0, 1.0)
else:
self.saturation = normalize(s)
if isinstance(v, float):
self.value = clamp(v, 0.0, 1.0)
else:
self.value = normalize(v)
def __repr__(self): # pylint: disable=invalid-repr-returned
return (self.hue, self.saturation, self.value)
def __str__(self):
return "(%s, %s, %s)" % (self.hue, self.saturation, self.value)
def __len__(self):
"""Retrieve total number of 'color-parts' available."""
return 3
def __getitem__(self, key):
"""Retrieve hue, saturation or value as iterable."""
if key == 0:
return self.hue
if key == 1:
return self.saturation
if key == 2:
return self.value
raise IndexError
[docs] def pack(self):
"""'Pack' a `CHSV` color into a 24-bit RGB integer.
:returns: 24-bit integer a la ``0x00RRGGBB``.
"""
# Convert CHSV to CRGB, return packed result
return CRGB(self).pack()
[docs]def clamp(val, lower, upper):
"""Constrain value within a numeric range (inclusive)."""
return max(lower, min(val, upper))
[docs]def normalize(val, inplace=False):
"""Convert 8-bit (0 to 255) value to normalized (0.0 to 1.0) value.
Accepts integer, 0 to 255 range (input is clamped) or a list or tuple
of integers. In list case, 'inplace' can be used to control whether
the original list is modified (True) or a new list is generated and
returned (False).
Returns float, 0.0 to 1.0 range, or list of floats (or None if inplace).
"""
if isinstance(val, int):
# Divide by 255 (not 256) so maximum level is 1.0.
return clamp(val, 0, 255) / 255.0
# If not int, is assumed list or tuple.
if inplace:
# Modify list in-place (OK for lists, NOT tuples, no check made)
for i, n in enumerate(val):
val[i] = normalize(n)
return None
# Generate new list
return [normalize(n) for n in val]
[docs]def denormalize(val, inplace=False):
"""Convert normalized (0.0 to 1.0) value to 8-bit (0 to 255) value
Accepts float, 0.0 to 1.0 range or a list or tuple of floats. In
list case, 'inplace' can be used to control whether the original list
is modified (True) or a new list is generated and returned (False).
Returns integer, 0 to 255 range, or list of integers (or None if
inplace).
"""
# 'Denormalizing' math varies slightly from normalize(). This is on
# purpose. Multiply by 256 (NOT 255) and clip. This ensures that all
# fractional values fall into the correct 'buckets' -- e.g. 0.999
# should return 255, not 254 -- and that the buckets are all equal-
# sized (usu. method of adding 0.5 before int() would miss this).
if isinstance(val, float):
return clamp(int(val * 256.0), 0, 255)
# If not int, is assumed list or tuple.
if inplace:
# Modify the list in-place (OK for lists, NOT tuples, no check made)
for i, n in enumerate(val):
val[i] = denormalize(n)
return None
# Generate new list
return [denormalize(n) for n in val]
[docs]def unpack(val):
"""'Unpack' a 24-bit color into a `CRGB` instance.
:param int val: 24-bit integer a la ``0x00RRGGBB``.
:returns: CRGB color.
:rtype: CRGB
"""
# See notes in normalize() for math explanation. Large constants here
# avoid the usual shift-right step, e.g. 16711680.0 is 255 * 256 * 256,
# so we can just mask out the red and divide by this for 0.0 to 1.0.
return CRGB(
(val & 0xFF0000) / 16711680.0, # Red
(val & 0x00FF00) / 65280.0, # Green
(val & 0x0000FF) / 255.0,
) # Blue
[docs]def mix(color1, color2, weight2=0.5):
"""Blend between two colors using given ratio. Accepts two colors (each
may be `CRGB`, `CHSV` or packed integer), and weighting (0.0 to 1.0)
of second color.
:returns: `CRGB` color in most cases, `CHSV` if both inputs are `CHSV`.
"""
clamp(weight2, 0.0, 1.0)
weight1 = 1.0 - weight2
if isinstance(color1, CHSV):
if isinstance(color2, CHSV):
# Both colors are CHSV -- interpolate in HSV color space
# because of the way hue can cross the unit boundary...
# e.g. if the hues are 0.25 and 0.75, the center point is
# 0.5 (cyan)...but if you want hues to wrap the other way
# (with red at the center), you can have hues of 1.25 and 0.75.
hue = color1.hue + ((color2.hue - color1.hue) * weight2)
sat = color1.saturation * weight1 + color2.saturation * weight2
val = color1.value * weight1 + color2.value * weight2
return CHSV(hue, sat, val)
# Else color1 is HSV, color2 is RGB. Convert color1 to RGB
# before doing interpolation in RGB space.
color1 = CRGB(color1)
# If color2 is a packed integer, convert to CRGB instance.
if isinstance(color2, int):
color2 = unpack(color2)
else:
if isinstance(color2, CHSV):
# color1 is RGB, color2 is HSV. Convert color2 to RGB
# before interpolating in RGB space.
color2 = CRGB(color2)
elif isinstance(color2, int):
# If color2 is a packed integer, convert to CRGB instance.
color2 = unpack(color2)
# If color1 is a packed integer, convert to CRGB instance.
if isinstance(color1, int):
color1 = unpack(color1)
# Interpolate and return as CRGB type
return CRGB(
(color1.red * weight1 + color2.red * weight2),
(color1.green * weight1 + color2.green * weight2),
(color1.blue * weight1 + color2.blue * weight2),
)
GFACTOR = 2.7 # Default gamma-correction factor for function below
[docs]def gamma_adjust(val, gamma_value=None, brightness=1.0, inplace=False):
"""Provides gamma adjustment for single values, `CRGB` and `CHSV` types
and lists of any of these.
Works in one of three ways:
1. Accepts a single normalized level (0.0 to 1.0) and optional
gamma-adjustment factor (float usu. > 1.0, default if
unspecified is GFACTOR) and brightness (float 0.0 to 1.0,
default is 1.0). Returns a single normalized gamma-corrected
brightness level (0.0 to 1.0).
2. Accepts a single `CRGB` or `CHSV` type, optional single gamma
factor OR a (R,G,B) gamma tuple (3 values usu. > 1.0), optional
single brightness factor OR a (R,G,B) brightness tuple. The
input tuples are RGB even when a `CHSV` color is passed. Returns
a normalized gamma-corrected `CRGB` type (NOT `CHSV`!).
3. Accept a list or tuple of normalized levels, `CRGB` or `CHSV`
types (and optional gamma and brightness levels or tuples
applied to all). Returns a list of gamma-corrected values or
`CRGB` types (NOT `CHSV`!).
In cases 2 and 3, if the input is a list (NOT a tuple!), the 'inplace'
flag determines whether a new tuple/list is calculated and returned,
or the existing value is modified in-place. By default this is
'False'. If you try to inplace-modify a tuple, an exception is raised.
In cases 2 and 3, there is NO return value if 'inplace' is True --
the original values are modified.
"""
# pylint: disable=too-many-branches
if isinstance(val, float):
# Input value appears to be a single float
if gamma_value is None:
gamma_value = GFACTOR
return pow(val, gamma_value) * brightness
if isinstance(val, (list, tuple)):
# List or tuple of values
if isinstance(val[0], float):
# Input appears to be a list of floats
if gamma_value is None:
gamma_value = GFACTOR
if inplace:
for i, x in enumerate(val):
val[i] = pow(val[i], gamma_value) * brightness
return None
newlist = []
for x in val:
newlist.append(pow(x, gamma_value) * brightness)
return newlist
# List of CRGB or CHSV...we'll get back to that in a moment...
# but first determine gamma-correction factors for R,G,B:
if gamma_value is None:
# No gamma specified, use default
gamma_red, gamma_green, gamma_blue = GFACTOR, GFACTOR, GFACTOR
elif isinstance(gamma_value, float):
# Single gamma value provided, apply to R,G,B
gamma_red, gamma_green, gamma_blue = (gamma_value, gamma_value, gamma_value)
else:
gamma_red, gamma_green, gamma_blue = (
gamma_value[0],
gamma_value[1],
gamma_value[2],
)
if isinstance(brightness, float):
# Single brightness value provided, apply to R,G,B
brightness_red, brightness_green, brightness_blue = (
brightness,
brightness,
brightness,
)
else:
brightness_red, brightness_green, brightness_blue = (
brightness[0],
brightness[1],
brightness[2],
)
if inplace:
for i, x in enumerate(val):
if isinstance(x, CHSV):
x = CRGB(x)
val[i] = CRGB(
pow(x.red, gamma_red) * brightness_red,
pow(x.green, gamma_green) * brightness_green,
pow(x.blue, gamma_blue) * brightness_blue,
)
return None
newlist = []
for x in val:
if isinstance(x, CHSV):
x = CRGB(x)
newlist.append(
CRGB(
pow(x.red, gamma_red) * brightness_red,
pow(x.green, gamma_green) * brightness_green,
pow(x.blue, gamma_blue) * brightness_blue,
)
)
return newlist
# Single CRGB or CHSV value
if gamma_value is None:
# No gamma specified, use default
gamma_red, gamma_green, gamma_blue = GFACTOR, GFACTOR, GFACTOR
elif isinstance(gamma_value, float):
# Single gamma value provided, apply to R,G,B
gamma_red, gamma_green, gamma_blue = (gamma_value, gamma_value, gamma_value)
else:
gamma_red, gamma_green, gamma_blue = (
gamma_value[0],
gamma_value[1],
gamma_value[2],
)
if isinstance(brightness, float):
# Single brightness value provided, apply to R,G,B
brightness_red, brightness_green, brightness_blue = (
brightness,
brightness,
brightness,
)
else:
brightness_red, brightness_green, brightness_blue = (
brightness[0],
brightness[1],
brightness[2],
)
if isinstance(val, CHSV):
val = CRGB(val)
return CRGB(
pow(val.red, gamma_red) * brightness_red,
pow(val.green, gamma_green) * brightness_green,
pow(val.blue, gamma_blue) * brightness_blue,
)
[docs]def palette_lookup(palette, position):
"""Fetch color from color palette, with interpolation.
:param palette: color palette (list of CRGB, CHSV and/or packed integers)
:param float position: palette position (0.0 to 1.0, wraps around).
:returns: `CRGB` or `CHSV` instance, no gamma correction applied.
"""
position %= 1.0 # Wrap palette position in 0.0 to <1.0 range
weight2 = position * len(palette) # Scale position to palette length
idx = int(floor(weight2)) # Index of 'lower' color (0 to len-1)
weight2 -= idx # Weighting of 'upper' color
color1 = palette[idx] # Fetch 'lower' color
idx = (idx + 1) % len(palette) # Get index of 'upper' color
color2 = palette[idx] # Fetch 'upper' color
return mix(color1, color2, weight2)
[docs]def expand_gradient(gradient, length):
"""Convert gradient palette into standard equal-interval palette.
:param sequence gradient: List or tuple of of 2-element lists/tuples
containing position (0.0 to 1.0) and color (packed int, CRGB or CHSV).
It's OK if the list/tuple elements are either lists OR tuples, but
don't mix and match lists and tuples -- use all one or the other.
:returns: CRGB list, can be used with palette_lookup() function.
"""
gradient = sorted(gradient) # Sort list by position values
least = gradient[0][0] # Lowest position value (ostensibly 0.0)
most = gradient[-1][0] # Highest position value (ostensibly 1.0)
newlist = []
for i in range(length):
pos = i / float(length - 1) # 0.0 to 1.0 in 'length' steps
# Determine indices in list of item 'below' and 'above' pos
if pos <= least:
# Off bottom of list - use lowest index
below, above = 0, 0
elif pos >= most:
# Off top of list - use highest index
below, above = -1, -1
else:
# Seek position between two items in list
below, above = 0, -1
for n, x in enumerate(gradient):
if pos >= x[0]:
below = n
for n, x in enumerate(gradient[-1:0:-1]):
if pos <= x[0]:
above = -1 - n
# Range between below, above
r = gradient[above][0] - gradient[below][0]
if r <= 0:
newlist.append(gradient[below][1]) # Use 'below' color only
else:
weight2 = (pos - gradient[below][0]) / r # Weight of 'above' color
color1 = gradient[below][1]
color2 = gradient[above][1]
# Interpolate and add to list
newlist.append(mix(color1, color2, weight2))
return newlist