spectroshaker/code.py

"""
Spectroshaker by The Dod:
Adafruit CircuitPlayground Bluefruit dual-mode "bling"
The RGB levels of neopixels around the circuit indicate:
- Low/Mid/High sound levels (spectrogram mode)
- X/Y/Z acceleration (shaker mode)

Controls:
    slider switch: normal/standby mode
    button a: toggle between spectrogram/shaker mode
    button b: cycle between 4 brightness levels

"""
import math
import time
from adafruit_circuitplayground import cp
from teaandtechtime_fft import spectrogram

NUM_PIXELS = 10
# Like a clock, with connectors at 12 (USB) and 6 (power)
LED_ANGLES = [
    i*math.pi/6.0
    for i in [11, 10, 9, 8, 7, 5, 4, 3, 2, 1]]

minx = miny = minz = -5.0
maxx = maxy = maxz = 5.0

fft_size = 8  # power of 2
samples = [0.0+0.0j]*fft_size
MAX_2FREQ = 10.0  # After testing this a bit in the wild

cp.pixels.brightness = 0.1

MODE_SPECTRO = 1
MODE_SHAKER = 2
current_mode = MODE_SHAKER
is_standby = cp.switch
last_click = 0
DEBOUNCE = 0.25

def angles2level(led, val):
    led_angle = LED_ANGLES[led]
    val_angle = val * 2.0 * math.pi
    angle = led_angle - val_angle
    while angle > 2 * math.pi:
        angle -= 2*math.pi
    # the pow() makes sin() values sharper
    return int(255*pow(math.sin(angle/2), 4))

while True:
    if time.monotonic() > last_click+DEBOUNCE:
        if is_standby != cp.switch:
            is_standby = cp.switch
            last_click = time.monotonic()
            if is_standby:
                for i in range(NUM_PIXELS):
                    cp.pixels[i] = (0, 0, 0)
        if cp.button_a:
            last_click = time.monotonic()
            current_mode = (
                current_mode == MODE_SHAKER and MODE_SPECTRO
                or MODE_SHAKER)
        elif cp.button_b:
            last_click = time.monotonic()
            is_standby = False
            if cp.pixels.brightness >= 0.4:
                cp.pixels.brightness = 0.1
            else:
                cp.pixels.brightness += 0.1

    if not is_standby:
        samples.pop(0)
        samples.append(cp.sound_level+0.0j)
        x, y, z = cp.acceleration
        if x < minx:
            minx = x
        if y < miny:
            miny = y
        if z < minz:
            minz = z
        if x > maxx:
            maxx = x
        if y > maxy:
            maxy = y
        if z > maxz:
            maxz = z
        if current_mode == MODE_SHAKER:  # accelerometer mode
            vals = (
                (x-minx)/(maxx-minx),
                (y-miny)/(maxy-miny),
                (z-minz)/(maxz-minz))
        else:  # spectrogram mode
            raw_freqs = spectrogram(samples)
            pairs = [raw_freqs[i]+raw_freqs[i+1] for i in range(fft_size//2)]
            vals = [min(1.0, abs(x/MAX_2FREQ)) for x in pairs[:3]]
        for i in range(NUM_PIXELS):
            cp.pixels[i] = (
                angles2level(i, vals[0]),
                angles2level(i, vals[1]),
                angles2level(i, vals[2]))
    time.sleep(0.01)