createCanvas(400, 400);

  var butt=createButton("Press Here");

  background("skyblue");

  text("Press when lightning obvserved.", 100,100);

}

​

var timestart;         // Millis at the first press

var timeend;           // Millis at the second press

var timediff;          // Time difference between the 2

var presscount=0;      // Tracks whether its 1st/2nd press

var dis;                // Calculates the distance

​

​

function draw() {

  //background(220);

}

​

//function mousePressed()

function touchStarted()

{

background("skyblue");

text("Press again when thunder heard to calculate distance.", 100,100);

presscount++;

if(presscount%2)

{

timestart=millis();

}

else

{

background("skyblue");

timeend=millis(); 

​

timediff=timeend-timestart;

timediff=timediff/1000;

//console.log("Time: " + round(timediff, 2) + " seconds");  

dis=timediff*343;      // number of seconds * speed sound

​

dis=dis/1609.34;       // Convert meters to miles

//console.log("Approx distance: " + round(dis,2) + " miles");   

text("Distance approx: " + round(dis,2) + " miles.", 100,100);

text("Press again when lighning observed.", 100, 300);

}

​

}