蛍

let num =25;

let vecLocation=[];

let vecVelocity=[];

​

​

function setup() {

  createCanvas(windowWidth,windowHeight);

  frameRate(30);

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

    vecLocation[i] =createVector(random(0,windowWidth),random(0,windowHeight));

  }

}

​

function draw() {

  background(72,61,110);

  noStroke();

  fill(238,173,14,random(30,200));

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

    let size=random(2,20)

    vecVelocity[i] =createVector(random(-10,10),random(-3,3));

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

    ellipse(vecLocation[i].x,vecLocation[i].y,size,size);

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

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

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

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

    }

  }