def ColorFromPalette(pal, pos, brightness=255, blend=False):
""" Approximates the FastLED ColorFromPalette() function
ACCEPTS: color palette (list of CRGB, CSHV and/or packed ints),
palette index (x16) + blend factor of next index (0-15) --
e.g. pass 32 to retrieve palette index 2, or 40 for an
interpolated value between palette index 2 and 3, optional
brightness (0-255), optional blend flag (True/False)
RETURNS: CRGB color, no gamma correction
"""
# Alter 'pos' from FastLED-like behavior to fancyled range
if blend:
# Continuous interpolation 0.0 to 1.0
pos = (pos / 16.0) / len(pal)
else:
# No blending -- quantize to nearest palette bin
pos = floor(pos / 16.0) / len(pal)
color = fancy.palette_lookup(pal, pos)
if brightness < 1.0:
brightness /= 255.0
if isinstance(color, fancy.CHSV):
color = fancy.CRGB(color)
elif isinstance(color, int):
color = fancy.unpack(color)
color.red *= brightness
color.green *= brightness
color.blue *= brightness
return color
def hsv2rgb_spectrum(hue, sat, val):
""" This is named the same thing as FastLED's simpler HSV to RGB function
(spectrum, vs rainbow) but implementation is a bit different for the
sake of getting something running (adapted from some NeoPixel code).
ACCEPTS: hue, saturation, value in range 0 to 255
RETURNS: CRGB color.
"""
return fancy.CRGB(fancy.CHSV(hue / 255, sat / 255, val / 255))
def loadDynamicGradientPalette(src, size):
""" Kindasorta like FastLED's loadDynamicGradientPalette() function,
with some gotchas.
ACCEPTS: Gradient palette data as a 'bytes' type (makes it easier to copy
over gradient palettes from existing FastLED Arduino sketches)...
each palette entry is four bytes: a relative position (0-255)
within the overall resulting palette (whatever its size), and
3 values for R, G and B...and a length for a new palette list
to be allocated.
RETURNS: list of CRGB colors.
"""
# Convert gradient from bytelist (groups of 4) to list of tuples,
# each consisting of a position (0.0 to 1.0) and CRGB color.
# (This is what FancyLED's expand_gradient needs for input.)
grad = []
for i in range(0, len(src), 4):
grad.append((src[i] / 255.0, fancy.CRGB(src[i+1], src[i+2], src[i+3])))
# Create palette (CRGB list) matching 'size' length
return fancy.expand_gradient(grad, size)
