Blob basic

let diameter; //直径

let position; //位置

let velocity; //速度

​

function setup() {

  //初期設定

  createCanvas(windowWidth, windowHeight);

  diameter = 100.0;

  position = createVector(width / 2, height / 2);

  velocity = createVector(random(-2, 2), random(2, 2));

}

​

function draw() {

  background(0);

  position.add(velocity); //位置を更新

  //壁でバウンド

  if (position.x < diameter / 2 || position.x > width - diameter / 2) {

    velocity.x *= -1;

  }

  if (position.y < diameter / 2 || position.y > height - diameter / 2) {

    velocity.y *= -1;

  }

  //色の設定

  noStroke();

  fill(255, 127);

  //プヨプヨする動きを計算

  currentDiameter = sin(frameCount * 0.1) * (diameter / 4) + diameter;

  //周囲の円を描画

  circle(position.x, position.y, currentDiameter);

  //核となる円を描画

  fill(255);

  circle(position.x, position.y, diameter / 6.0);

}