/* NeoPixel LED Ring 彩虹特效
  202208 - 13 NeoPixel LED Ring 彩虹特效
  Created by Jason on 13 Aug 2022.
  https://wokwi.com/projects/338857849104892500
*/

#include <Adafruit_NeoPixel.h>

#define DATA_PIN  13
#define NUMPIXELS 24  // NeoPixel ring size
#define pixDELAY  10  // Delay for pixel persistence

// 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)
//   NEO_RGBW    Pixels are wired for RGBW bitstream (NeoPixel RGBW products)
Adafruit_NeoPixel ring = Adafruit_NeoPixel(NUMPIXELS, DATA_PIN, NEO_GRB + NEO_KHZ800); // 建立物件 (24 = LED 數量, 13 = Pin)

// 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.

void setup() {
  ring.begin();
  ring.setBrightness(255); // 設定亮度 0 - 255
  ring.show(); // 將設定顯示出來
}

void loop() {
  rainbowCycle(pixDELAY); // 彩虹滾動圈圈
}

// 彩虹滾動圈圈
void rainbowCycle(int wait) {
  int i, j;

  for (j = 0; j < 256 * 5; j++) {
    for (i = 0; i < ring.numPixels(); i++) {
      ring.setPixelColor(i, Wheel(((i * 256 / ring.numPixels()) + j) & 255));
    }
    ring.show();
    delay(wait);
  }
}

// 產生漸變顏色值
int32_t Wheel(byte WheelPos) {
  WheelPos = 255 - WheelPos;
  if (WheelPos < 85) {
    return ring.Color(255 - WheelPos * 3, 0, WheelPos * 3);
  }
  if (WheelPos < 170) {
    WheelPos -= 85;
    return ring.Color(0, WheelPos * 3, 255 - WheelPos * 3);
  }
  WheelPos -= 170;
  return ring.Color(WheelPos * 3, 255 - WheelPos * 3, 0);
}