NeoPixel Coding Help

[dungeon_duets]

Hey there! So I'm pretty new to Arduino and coding, and have a cosplay project with NeoPixels I'm working with. I'm working with the code below that I found to get a twinkling effect, but I'd like to change it up to only flash in a few specific colors, rather than the fully random colors I'm getting now. Can anyone show me where I need to change or add to the code to specify the colors?

#include <Adafruit_NeoPixel.h>

#define PIN 6
#define Pixels 16

// Parameter 1 = number of pixels in strip
// Parameter 2 = Arduino pin number (most are valid)
// Parameter 3 = pixel type flags, add together as needed:
// NEO_KHZ800 800 KHz bitstream (most NeoPixel products w/WS2812 LEDs)
// NEO_KHZ400 400 KHz (classic 'v1' (not v2) FLORA pixels, WS2811 drivers)
// NEO_GRB Pixels are wired for GRB bitstream (most NeoPixel products)
// NEO_RGB Pixels are wired for RGB bitstream (v1 FLORA pixels, not v2)
Adafruit_NeoPixel strip = Adafruit_NeoPixel(Pixels, PIN, NEO_GRB + NEO_KHZ800);

// IMPORTANT: To reduce NeoPixel burnout risk, add 1000 uF capacitor across
// pixel power leads, add 300 - 500 Ohm resistor on first pixel's data input
// and minimize distance between Arduino and first pixel. Avoid connecting
// on a live circuit...if you must, connect GND first.

float redStates[Pixels];
float blueStates[Pixels];
float greenStates[Pixels];
float fadeRate = 0.96;

void setup() {
strip.begin();
strip.show(); // Initialize all pixels to 'off'

for(uint16_t l = 0; l < Pixels; l++) {
redStates[l] = 0;
greenStates[l] = 0;
blueStates[l] = 0;
}
}

void loop () {
if (random(20) == 1) {
uint16_t i = random(Pixels);
if (redStates[i] < 1 && greenStates[i] < 1 && blueStates[i] < 1) {
redStates[i] = random(256);
greenStates[i] = random(256);
blueStates[i] = random(256);
}
}

for(uint16_t l = 0; l < Pixels; l++) {
  if (redStates[l] > 1 || greenStates[l] > 1 || blueStates[l] > 1) {
    strip.setPixelColor(l, redStates[l], greenStates[l], blueStates[l]);

    if (redStates[l] > 1) {
      redStates[l] = redStates[l] * fadeRate;
    } else {
      redStates[l] = 0;
    }

    if (greenStates[l] > 1) {
      greenStates[l] = greenStates[l] * fadeRate;
    } else {
      greenStates[l] = 0;
    }

    if (blueStates[l] > 1) {
      blueStates[l] = blueStates[l] * fadeRate;
    } else {
      blueStates[l] = 0;
    }

  } else {
    strip.setPixelColor(l, 0, 0, 0);
  }
}
strip.show();
delay(10);

}

[LarryD]

You can limit the numbers here:

redStates[i]   = random(256);
greenStates[i] = random(256);
blueStates[i]  = random(256);

See:
random(min, max)

random() - Arduino Reference

[Grumpy_Mike]

Or you can use a much smaller range of random numbers, say 8, and then get them to the full range by multiplying by 32.