"Magic lamp" with Arduino

// ************************************************** ***************************************************** ********** //
#include
#include

#define blank_pin 3 // Defines actual BIT of PortD for blank - is Arduino UNO pin 3
#define latch_pin 2 // Defines actual BIT of PortD for latch - is Arduino UNO pin 2
#define clock_pin 13 // used by SPI, must be 13 SCK 13 on Arduino UNO
#define data_pin 11 // used by SPI, must be pin MOSI 11 on Arduino UNO

#define ROW 4
#define BUTTON 5
#define PIN 6
#define POTPIN 7

Adafruit_NeoPixel strip = Adafruit_NeoPixel (16, PIN, NEO_GRB + NEO_KHZ800);

// ************************************************** ***************************************************** ********** //

byte red [4];
byte green [4];
byte blue [4];

int BAM_Bit, BAM_Counter = 0;

// ************************************************** ***************************************************** ********** //
#define BAM_RESOLUTION 4
#define COLOR_WHEEL_LENGTH 256

uint8_t colourR [COLOR_WHEEL_LENGTH];
uint8_t colourG [COLOR_WHEEL_LENGTH];
uint8_t colourB [COLOR_WHEEL_LENGTH];
int16_t ColPos = 0;
uint16_t colourPos;
uint8_t R, G, B;

#define myPI 3.14159265358979323846
#define myDPI 1.2732395
#define myDPI2 0.40528473

int buttonPushCounter = 0;
int buttonState = 0;
int lastButtonState = 0;
int POT;
int OLD_POT;

void setup ()
{
strip.begin ();
strip.setBrightness (50);
strip.show (); // Initialize all pixels to 'off'

SPI.setBitOrder (MSBFIRST);
SPI.setDataMode (SPI_MODE0);
SPI.setClockDivider (SPI_CLOCK_DIV2);

noInterrupts ();

TCCR1A = B00000000;
TCCR1B = B00001011;
TIMSK1 = B00000010;
OCR1A = 8;

pinMode (latch_pin, OUTPUT);
pinMode (data_pin, OUTPUT);
pinMode (clock_pin, OUTPUT);

pinMode (ROW, OUTPUT);
pinMode (BUTTON, INPUT_PULLUP);

SPI.begin ();
interrupts ();

fill_colour_wheel ();
clearfast ();
}

void loop ()
{
buttonState = digitalRead (BUTTON);
 
  if (buttonState! = lastButtonState) {
    if (buttonState == HIGH) {
      buttonPushCounter ++;
    }
    else {

    }
  }
  lastButtonState = buttonState;

  switch (buttonPushCounter% 5)
  {
    case 0:

      POT = map (analogRead (POTPIN), 0, 1023, 0, 255);
      if (POT & lt; (OLD_POT * 0.95) || POT & gt; (OLD_POT * 1.05))
        {
          OLD_POT = POT; // save the changed value
          fillTable_colorwheelRGB (POT, R, G, B);
          rainbow (POT);
        }

        break;
    case 1:

      POT = map (analogRead (POTPIN), 0, 1023, 0, 255);
      if (POT & lt; (OLD_POT * 0.95) || POT & gt; (OLD_POT * 1.05))
        {
          OLD_POT = POT;
          get_colour (POT, & R, & G, & B);
          fillTable (R, G, B);
          fillring (POT);
        }

        break;

    case 2:

      POT = map (analogRead (POTPIN), 0, 1023, 0, 255);
      if (POT & lt; (OLD_POT * 0.95) || POT & gt; (OLD_POT * 1.05))
        {
          OLD_POT = POT;
          get_colour (POT, & R, & G, & B);
          fillTable (R, G, B);
          fullWhite ();
        }

        break;
    case 3:

      POT = map (analogRead (POTPIN), 0, 1023, 0, 255);
      if (POT & lt; (OLD_POT * 0.95) || POT & gt; (OLD_POT * 1.05))
        {
          OLD_POT = POT;
          fillTable (0, 0, 0);
          rainbow (POT);
        }

        break;
case 4:
        clearfast ();
        fullWhite ();
        break;
  }
}

void LED (int Y, int R, int G, int B)
{
  Y = constrain (Y, 0, 7);
  
  R = constrain (R, 0, 15);
  G = constrain (G, 0, 15);
  B = constrain (B, 0, 15);

  for (byte BAM = 0; BAM & lt; BAM_RESOLUTION; BAM ++)
  {
    bitWrite (red [BAM], Y, bitRead (R, BAM));

    bitWrite (green [BAM], Y, bitRead (G, BAM));

    bitWrite (blue [BAM], Y, bitRead (B, BAM));
  }
}

ISR (TIMER1_COMPA_vect) {
  
PORTD | = ((1 & lt; myPI) {
    x - = 2 * myPI;
    g is 1;
  }

  while (! g & (x & lt; -myPI)) {
    x + = 2 * myPI;
  }

  sinr = myDPI * x - myDPI2 * x * myAbs (x);
  sinr = 0.225 * (sinr * myAbs (sinr) -sinr) + sinr;

  return sinr;
}

// FAST COSINE APPROX
float myCos (float x) {
  return mySin (x + myPI / 2);
}

float myTan (float x) {
  return mySin (x) / myCos (x);
}

// SQUARE ROOT APPROX
float mySqrt (float in) {
  int16_t d = 0;
  int16_t in_ = in;
  float result = 2;
  
  for (d = 0; in_ & gt; 0; in_ & gt; & gt; = 1) {
    d ++;
  }
  
  for (int16_t i = 0; i & lt; d / 2; i ++) {
    result = result * 2;
  }
  
  for (int16_t i = 0; i & lt; 3; i ++) {
    result = 0.5 * (in / result + result);
  }
  
  return result;
}

// ABSOLUTE VALUE
float myAbs (float in) {
  return (in) & gt; 0? (in) :-( in);
}

void fill_colour_wheel (void)
{
  float red, green, blue;
  float c, s;
  int32_t phase = 0;
  int16_t I = 0;

  while (phase & lt; COLOR_WHEEL_LENGTH)
  {
    s = (1 & lt; & lt; BAM_RESOLUTION) * mySin (myPI * (3 * phase - I * COLOR_WHEEL_LENGTH) / (2 * COLOR_WHEEL_LENGTH));
    c = (1 & lt; & lt; BAM_RESOLUTION) * myCos (myPI * (3 * phase - I * COLOR_WHEEL_LENGTH) / (2 * COLOR_WHEEL_LENGTH));

    red = (I == 0? 1: 0) * s + (I == 1? 1: 0) * c;
    green = (I == 1? 1: 0) * s + (I == 2? 1: 0) * c;
    blue = (I == 2? 1: 0) * s + (I == 0? 1: 0) * c;

    colourR [phase] = red;
    colourG [phase] = green;
    colourB [phase] = blue;

    if (++ phase & gt; = (1 + I) * COLOR_WHEEL_LENGTH / 3)
      I ++;
  }
}

void get_colour (int16_t p, uint8_t * R, uint8_t * G, uint8_t * B)
{
  if (p & gt; = COLOR_WHEEL_LENGTH)
    p - = COLOR_WHEEL_LENGTH;

  * R = colourR [p];
  * G = colourG [p];
  * B = colourB [p];
}

void get_next_colour (uint8_t * R, uint8_t * G, uint8_t * B)
{
  if (++ ColPos & gt; = COLOR_WHEEL_LENGTH)
    ColPos - = COLOR_WHEEL_LENGTH;

  * R = colourR [ColPos];
  * G = colourG [ColPos];
  * B = colourB [ColPos];
}

void increment_colour_pos (uint8_t i)
{
  colourPos + = i;
  while (colourPos & gt; = COLOR_WHEEL_LENGTH)
  {
    colourPos - = COLOR_WHEEL_LENGTH;
  }
}

// Input a value 0 to 255 to get a color value.
// The colors are a transition r - g - b - back to r.
uint32_t Wheel (byte WheelPos) {
  WheelPos = 255 - WheelPos;
  if (WheelPos & lt; 85) {
    return strip.Color (255 - WheelPos * 3, 0, WheelPos * 3);
  }
  if (WheelPos & lt; 170) {
    WheelPos - = 85;
    return strip.Color (0, WheelPos * 3, 255 - WheelPos * 3);
  }
  WheelPos - = 170;
  return strip.Color (WheelPos * 3, 255 - WheelPos * 3, 0);
}