Simple FastLED "sunrise" example that fades from black to red, orange, yellow, and white.

FastLED-Sunrise.ino

#include "FastLED.h"

// How many leds in your strip?
#define NUM_LEDS 60

// For led chips like Neopixels, which have a data line, ground, and power, you just
// need to define DATA_PIN.  For led chipsets that are SPI based (four wires - data, clock,
// ground, and power), like the LPD8806 define both DATA_PIN and CLOCK_PIN
#define DATA_PIN 3
#define CLOCK_PIN 13

// Define the array of leds
CRGB leds[NUM_LEDS];

void setup() { 
      // Uncomment/edit one of the following lines for your leds arrangement.
      // FastLED.addLeds<TM1803, DATA_PIN, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<TM1804, DATA_PIN, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<TM1809, DATA_PIN, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<WS2811, DATA_PIN, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<WS2812, DATA_PIN, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<WS2812B, DATA_PIN, RGB>(leds, NUM_LEDS);
      FastLED.addLeds<NEOPIXEL, DATA_PIN>(leds, NUM_LEDS);
      // FastLED.addLeds<APA104, DATA_PIN, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<UCS1903, DATA_PIN, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<UCS1903B, DATA_PIN, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<GW6205, DATA_PIN, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<GW6205_400, DATA_PIN, RGB>(leds, NUM_LEDS);
      
      // FastLED.addLeds<WS2801, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<SM16716, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<LPD8806, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<P9813, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<APA102, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<DOTSTAR, RGB>(leds, NUM_LEDS);

      // FastLED.addLeds<WS2801, DATA_PIN, CLOCK_PIN, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<SM16716, DATA_PIN, CLOCK_PIN, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<LPD8806, DATA_PIN, CLOCK_PIN, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<P9813, DATA_PIN, CLOCK_PIN, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<APA102, DATA_PIN, CLOCK_PIN, RGB>(leds, NUM_LEDS);
      // FastLED.addLeds<DOTSTAR, DATA_PIN, CLOCK_PIN, RGB>(leds, NUM_LEDS);
}

void loop() { 
  sunrise();
  
  FastLED.show();
}

void sunrise() {
  
  // total sunrise length, in minutes
  static const uint8_t sunriseLength = 30;

  // how often (in seconds) should the heat color increase?
  // for the default of 30 minutes, this should be about every 7 seconds
  // 7 seconds x 256 gradient steps = 1,792 seconds = ~30 minutes
  static const uint8_t interval = (sunriseLength * 60) / 256;

  // current gradient palette color index
  static uint8_t heatIndex = 0; // start out at 0

  // HeatColors_p is a gradient palette built in to FastLED
  // that fades from black to red, orange, yellow, white
  // feel free to use another palette or define your own custom one
  CRGB color = ColorFromPalette(HeatColors_p, heatIndex);

  // fill the entire strip with the current color
  fill_solid(leds, NUM_LEDS, color);

  // slowly increase the heat
  EVERY_N_SECONDS(interval) {
    // stop incrementing at 255, we don't want to overflow back to 0
    if(heatIndex < 255) {
      heatIndex++;
    }
  }
}

You will need to rest the heatIndex back to zero. Even if you reset the register for heatIndex sill has the value of 255.

Before setup add heatIndex = 0;

And to rest at the end, in void sunrise()
EVERY_N_SECONDS(interval) {
// stop incrementing at 255, we don't want to overflow back to 0
if (heatIndex < 255) {
heatIndex++;
}
if (heatIndex == 255) {
heatIndex = 0;
}

how do you turn the leds on?

You turn them on with FastLED.show();

Hi

I'm looking to set up a sunrise effect in FastLED via ESPHome.
Can I (and how would I) use this script somehow within ESPHome?

Kr

PS: can ColorFromPaletteExtended() (FastLED/FastLED#202) be integrated in this?

COuld be a dumb question but how do i speed this up? i have changed sunrise length but i just see white

Setting the duration too low will cause interval to be 0 hence why immediately white. I suggest to just temporarily hardcode the interval to 1 if you want to speed it up. The full runtime will be about 4 min 16 secs