function clamp(x, min_x, max_x) {
    return min(max(x, min_x), max_x)
}

class Walker {
    constructor(x = 0, y = 0) {
        this.pos = createVector(x, y)
    }

    step() {
        let vel = createVector(0, 0)
        if (random(1) < 0.5) {
            vel.x = clamp(mouseX - this.pos.x, -1, 1)
            vel.y = clamp(mouseY - this.pos.y, -1, 1)
        } else {
            vel.x = floor(random(3)) - 1
            vel.y = floor(random(3)) - 1
        }

        this.pos.add(vel)
    }

    draw() {
        stroke(0)
        point(this.pos)
    }
}

let walker

function setup() {
    createCanvas(640, 240)
    background(255)
    walker = new Walker(320, 120)
}

function draw() {
    walker.step();
    walker.draw();
}