leds.ino

#include <FastLED.h>

#define LED_COUNT 10

CRGB leds[LED_COUNT];

int lastPot = -100;
float col[3];

void setup() {
  Serial.begin(115200);
  
  pinMode(0, INPUT);

  pinMode(2, OUTPUT);
  FastLED.addLeds<NEOPIXEL, 2>(leds, LED_COUNT);
}

void loop() {
  int potVal = analogRead(A0);
  int diff = abs(potVal - lastPot);
  if (diff > 20) {
    Serial.println(potVal);
    lastPot = potVal;

    hsv2rgb(potVal / 730.0, 1.0, 1.0, col);
    for(int i=0; i < LED_COUNT; i++) {
      leds[i].setRGB(col[0] * 255, col[1] * 255, col[2] * 255);
    }
  }
  

  FastLED.show();
}

float fract(float x) { return x - int(x); }

float mix(float a, float b, float t) { return a + (b - a) * t; }

float* hsv2rgb(float h, float s, float b, float* rgb) {
  rgb[0] = b * mix(1.0, constrain(abs(fract(h + 1.0) * 6.0 - 3.0) - 1.0, 0.0, 1.0), s);
  rgb[1] = b * mix(1.0, constrain(abs(fract(h + 0.6666666) * 6.0 - 3.0) - 1.0, 0.0, 1.0), s);
  rgb[2] = b * mix(1.0, constrain(abs(fract(h + 0.3333333) * 6.0 - 3.0) - 1.0, 0.0, 1.0), s);
  return rgb;
}