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

const dot = 1;              //min = 0, max = 1, step = 1, (white, black)
const size = 90;
const grid = 100;
let radius = 0.7 * size / grid;

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

let x = 0;
let y = 0;

const xi = Math.floor(Math.random() * grid);
const yi = Math.floor(Math.random() * grid);

// The walk function will be called until it returns false.
function walk(i) {
    
    posx = x * (2 * size / grid) - size;
    posy = y * (2 * size / grid) - size;
    
    if(dot == 1){
        turtle.jump(posx, posy - radius);
        turtle.seth(0);
        turtle.circle(radius);
        
        if(x == xi && y == yi){
            for(let j = radius; j > 0 ; j -= 0.1){
                turtle.jump(posx, posy - j);
                turtle.seth(0);
                turtle.circle(j);
            }
        }
    } else {
        if(x != xi || y != yi){
            turtle.jump(posx, posy - radius);
            turtle.seth(0);
            turtle.circle(radius);
        }
    }

    

    if(x++ >= grid){
        x = 0;
        if(y++ >= grid) return false;
    }

    return true;
}