sketch.js

let x = 300; //円のX座標に使う変数
let y = 300;
let speedX = 5; //円の進む距離
let speedY = 3;
let iroMode = 1; //色モード
function setup() {
  createCanvas(600, 600); //ウィンドウサイズの指定
  background(0, 0, 0, 100); //背景色を指定して1回だけ塗る。
}

function draw() {
  background(255, 255, 255, 3); //背景色を指定して1回だけ塗る。
  noStroke();
  if (iroMode == 1) {
    fill(y, mouseX, mouseY);
  }
  if (iroMode == 2) {
    fill(mouseY, y, mouseX);
  }
  if (iroMode == 3) {
    fill(mouseX, mouseY, x);
  }
  if (iroMode == 4) {
    fill(mouseX, x, mouseY);
  }
  circle(x, y, 100);
  x = x + speedX;
  y = y + speedY;
  if (x > 550) {
    speedX = speedX * -1;
  }
  if (x < 50) {
    speedX = speedX * -1;
  }
  if (y > 550) {
    speedY = speedY * -1;
  }
  if (y < 50) {
    speedY = speedY * -1;
  }
}

function mousePressed() {
  //マウスのボタンが押し下げられた時の処理
}

function mouseReleased() {
  //マウスのボタンが離された時の処理
}

function keyPressed() {
  if (keyCode == UP_ARROW) {
    speedY = speedY - 3;
    iroMode = 1;
  }
  if (keyCode == DOWN_ARROW) {
    speedY = speedY + 3;
    iroMode = 2;
  }
  if (keyCode == LEFT_ARROW) {
    speedX = speedX - 3;
    iroMode = 3;
  }
  if (keyCode == RIGHT_ARROW) {
    speedX = speedX + 3;
    iroMode = 4;
  }
  if (key == "s") {
    saveCanvas();
  }
}