bLue

let vecLocation = [0]; //位置ベクトル

let vecVelocity = [0]; //速度ベクトル

const NUM = 100; //定数

​

function setup() {

  createCanvas(windowWidth,  windowHeight);

  frameRate(50); //60fps (Frame per Second)

  for(let i = 0; i < NUM; i++){

   vecLocation[i] = createVector(width/2, height/2);

  vecVelocity[i] = createVector(random(-10, 10), random(-10, 10)); 

  }

}

​

function draw() {

  background (0);

  noStroke();

  fill(random(50), random(225), random(255), random(100, 150));

  for(let i = 0; i < NUM; i++){

  ellipse(vecLocation[i].x, vecLocation[i].y, random(20, 50), random(20, 50));

  vecLocation[i].add(vecVelocity[i]);

  if(vecLocation[i].x > width || vecLocation[i].x < 0){

    vecVelocity[i].x = vecVelocity[i].x * -1;

  }

  if(vecLocation[i].y > height || vecLocation[i].y < 0){

    vecVelocity[i].y= vecVelocity[i].y * -1;

    }

  }

}