Modified to use WS2812

ThermalFlashlight.ino

// See http://bildr.org/2011/02/mlx90614-arduino/ for i2c library and instructions
// You must download the "twimaster.cpp" and "i2cmaster.h" files, and place them in a folder called "I2Cmaster". 
// This must be placed in a folder called "libraries" which in turn should be placed in your Sketchbook folder (see Arduino's Preferences menu item to see where this is on your machine.).
// Typically, once you install these files, you must relaunch Arduino.

// Starting from original project of Public Lab
// The extra files are included in this Gist, as well as attached to the page http://publiclaboratory.org/tool/thermal-camera

// Modified to use WS2812B Led

#include <i2cmaster.h>
#include "Wire.h"
//#include "BlinkM_funcs.h"

#include <Adafruit_NeoPixel.h>
// Which pin on the Arduino is connected to the NeoPixels?
#define PIN           10
// How many NeoPixels are attached to the Arduino?
#define NUMPIXELS      1

Adafruit_NeoPixel pixels = Adafruit_NeoPixel(NUMPIXELS, PIN, NEO_GRB + NEO_KHZ400);

const float lowReading = 60;
const float highReading = 75;
const unsigned char separatorCharacter = 255;

void setup(){
	Serial.begin(9600);
	Serial.println("starting setup...");

	pixels.begin(); // This initializes the NeoPixel library.

	pinMode(9, INPUT); 

	i2c_init(); //Initialise the i2c bus
	PORTC = (1 << PORTC4) | (1 << PORTC5);//enable pullups

	Serial.println("completed setup");

}

float normf(float x, float low, float high) {
	float y = (x - low) * 255.f / (high - low);
	if(y > 255) {
		y = 255;
	}
	if(y < 0) {
		y = 0;
	}
	return y;
}

void loop(){
	int dev = 0x5A<<1;
	int data_low = 0;
	int data_high = 0;
	int pec = 0;
        int x;
        
	i2c_start_wait(dev+I2C_WRITE);
	i2c_write(0x07);

	// read
	i2c_rep_start(dev+I2C_READ);
	data_low = i2c_readAck(); //Read 1 byte and then send ack
	data_high = i2c_readAck(); //Read 1 byte and then send ack
	pec = i2c_readNak();
	i2c_stop();

	//This converts high and low bytes together and processes temperature, MSB is a error bit and is ignored for temps
	double tempFactor = 0.02; // 0.02 degrees per LSB (measurement resolution of the MLX90614)
	double tempData = 0x0000; // zero out the data
	int frac; // data past the decimal point

	// This masks off the error bit of the high byte, then moves it left 8 bits and adds the low byte.
	tempData = (double)(((data_high & 0x007F) << 8) + data_low);
	tempData = (tempData * tempFactor)-0.01;
	float celsius = tempData - 273.15;
	float fahrenheit = (celsius*1.8) + 32;
	//Serial.println(fahrenheit);
	float state = normf(fahrenheit, lowReading, highReading);

	
	int hue = map(celsius,-15,50,15,315); // i primi due parametri indicano le temperatura minima e massima da misurare, i secondi il range di tonalità edl colore, per orientarsi http://hslpicker.com/
	setLedColorHSV(hue,1,1); //We are using Saturation and Value constant at 1
        Serial.print(state,2);
        Serial.print(" ");
	Serial.print(tempData);
	Serial.print(" gradi Kelvin, ");
	Serial.print(celsius);
	Serial.print(" gradi Celsius, ");
	Serial.print(330 - hue);
	Serial.println(" tonalita ");

}
//Convert a given HSV (Hue Saturation Value) to RGB(Red Green Blue) and set the led to the color
// h is hue value, integer between 0 and 360
// s is saturation value, double between 0 and 1
// v is value, double between 0 and 1
//http://splinter.com.au/blog/?p=29
void setLedColorHSV(int h, double s, double v) {
	//this is the algorithm to convert from RGB to HSV
	double r=0;
	double g=0;
	double b=0;

	double hf=h/60.0;

	int i=(int)floor(h/60.0);
	double f = h/60.0 - i;
	double pv = v * (1 - s);
	double qv = v * (1 - s*f);
	double tv = v * (1 - s * (1 - f));

	switch (i)
	{
		case 0: //rojo dominante
			r = v;
			g = tv;
			b = pv;
			break;
		case 1: //verde
			r = qv;
			g = v;
			b = pv;
			break;
		case 2:
			r = pv;
			g = v;
			b = tv;
			break;
		case 3: //azul
			r = pv;
			g = qv;
			b = v;
			break;
		case 4:
			r = tv;
			g = pv;
			b = v;
			break;
		case 5: //rojo
			r = v;
			g = pv;
			b = qv;
			break;
	}

	//set each component to a integer value between 0 and 255
	int red=constrain(255-(int)255*r,0,255);
	int green=constrain(255-(int)255*g,0,255);
	int blue=constrain(255-(int)255*b,0,255);

	setLedColor(red,green,blue);
}

//Sets the current color for the RGB LED
void setLedColor(int red, int green, int blue) {
	byte i = 0;                                             // posizione del led sul bus
	pixels.setPixelColor(i, pixels.Color(red,green,blue)); // Moderately bright green color.
	pixels.show(); 
}