Thunder Brush

function setup() {

  createCanvas(windowWidth, windowHeight);

}

​

let a = [];

​

function draw() {

  // background(220);

  if (mouseIsPressed) {

    fill(255, 220);

    rect(0, 0, width, height);

  a.push({mouseX, mouseY, xdist: mouseX-pmouseX, ydist: mouseY-pmouseY});

  a.forEach(({mouseX, mouseY, xdist, ydist}, index) => {

    // a[index].mouseX +=random(-1, 1)/(xdist+0.5);

    // a[index].mouseY += random(-1, 1)/(ydist+0.5);

    const m = 3;

    a[index].mouseX += random(-1, 1) * m

    a[index].mouseY += random(-1, 1) * m

    a[index].xdist /= 2;

    a[index].ydist /= 2;

    //print(a.length - index)

    stroke(a.length - index);

    for( let i = 1; i < 4; i++ ) {

    if (a[index -i]) {

      line(a[index].mouseX, a[index].mouseY, a[index - i].mouseX, a[index -i].mouseY);

    }

    }

​

  });

  } else {

    a = [];

  }

}