// You can find the Turtle API reference here: https://turtletoy.net/syntax
Canvas.setpenopacity(1);

// Global code will be evaluated once.
const turtle = new Turtle();

const xfreq=2;    
const xphrase=0.5;  //min=0 max=1 step=0.1
const damping=0.01; //min=0.01 max=0.1 step=0.01

const yfreq=-2;
const yphrase=0.7;  //min=0.1 max=1 step=0.1

const iteration=10000;

turtle.penup();
turtle.goto(getxcoor(0),getycoor(0));
turtle.pendown();

function getxcoor(t){
    var x;
    x = Math.sin(t*xfreq)*(-1*damping*t);
    return x;
}
function getycoor(t){
    y = Math.sin(yfreq*(t+yphrase))*(-1*damping*t);
    return y;
}
// The walk function will be called until it returns false.
function walk(i) {
    var time=i*10;
    turtle.goto(getxcoor(time),getycoor(time));
    return i+1 < iteration;
}