//import Serial communication library
import processing.serial.*;

//init variables
Serial commPort;
float tempC;
float tempF;
int yDist;
PFont font12;
PFont font24;
float[] tempHistory = new float[100];

void setup()
{
 //setup fonts for use throughout the application
 font12 = loadFont("Verdana-12.vlw"); 
 font24 = loadFont("Verdana-24.vlw"); 
 
 //set the size of the window
 size(210, 200);
 
 //init serial communication port
 commPort = new Serial(this, "COM10", 9600);
 
 //fill tempHistory with default temps
 for(int index = 0; index<100; index++)
 tempHistory[index] = 0;
}

void draw()
{
 //get the temp from the serial port
 while (commPort.available() > 0) 
 {
 tempC = commPort.read();
 
 //refresh the background to clear old data
 background(123);

 //draw the temp rectangle
 colorMode(RGB, 160); //use color mode sized for fading
 stroke (0);
 rect (49,19,22,162);
 //fade red and blue within the rectangle
 for (int colorIndex = 0; colorIndex <= 160; colorIndex++) 
 {
 stroke(160 - colorIndex, 0, colorIndex);
 line(50, colorIndex + 20, 70, colorIndex + 20);
 }
 
 //draw graph
 stroke(0);
 fill(255,255,255);
 rect(90,80,100,100);
 for (int index = 0; index<100; index++)
 { 
 if(index == 99)
 tempHistory[index] = tempC;
 else
 tempHistory[index] = tempHistory[index + 1];
 point(90 + index, 180 - tempHistory[index]); 
 }
 
 //write reference values
 fill(0,0,0);
 textFont(font12); 
 textAlign(RIGHT);
 text("212 F", 45, 25); 
 text("32 F", 45, 187);
 
 //draw triangle pointer
 yDist = int(160 - (160 * (tempC * 0.01)));
 stroke(0);
 triangle(75, yDist + 20, 85, yDist + 15, 85, yDist + 25);
 
 //write the temp in C and F
 fill(0,0,0);
 textFont(font24); 
 textAlign(LEFT);
 text(str(int(tempC)) + " C", 115, 37);
 tempF = ((tempC*9)/5) + 32;
 text(str(int(tempF)) + " F", 115, 65);
 }
}