createCanvas(510, 510);

  frameRate(3);

}

​

function draw() {

  let rColor = 255;

  let gColor = 255;

  let bColor = 255;

  background((random(mouseX, rColor), random(mouseY, gColor), random((mouseX+mouseY)/2, bColor)));

  let unitWidth = 20+mouseY/20;

  let unitHeight = 20+mouseY/20;

  let strokeWidth = 0.3+(mouseX/120);

  stroke(0, 0, 0);

  if (mouseIsPressed) {

    background(0);

    fill(255);

    let strokeWidth = 0

    stroke(0);

  }

  for (i=0; i<width; i=i+unitWidth) {

    for (k=0; k<height; k=k+unitHeight) {

      let x = round(random(3))

      fill(random(mouseX, rColor), random(mouseY, gColor), random((mouseX+mouseY)/2, bColor));

      if (mouseIsPressed) {

        //background(255);

        fill(0);

        let strokeWidth = 0

        stroke(255);

      }

      strokeWeight(strokeWidth);

      if (x==0){

        rect(i, k+unitHeight/2, i+unitWidth, k+unitHeight/2);

      } else if (x==1) {

        rect(i+unitWidth/2, k, i+unitWidth/2, k+unitHeight);

      } else if (x==2) {

        rect(i, k, i+unitWidth, k+unitHeight);

      } else if (x==3) {

        rect(i+unitWidth, k, i, k+unitHeight);

      }

    }

  }

}