window.addEventListener("load", init); function init() { var stage = new createjs.Stage("myCanvas"); // var ball = new createjs.Shape(); ball.graphics.beginFill('#888888').drawCircle(0, 0, 10); stage.addChild(ball); // var angle = 0; var centerX = stage.canvas.width / 2; var centerY = stage.canvas.height / 2; var radius = 100; var speed = .01; // 時間経過 createjs.Ticker.addEventListener("tick", handleTick); function handleTick() { ball.x = centerX + Math.cos(angle) * radius; ball.y = centerY + Math.sin(angle) * radius; angle += speed; stage.update(); // 画面更新 } // var bg = new createjs.Shape(); bg.graphics.setStrokeStyle(1).beginStroke("LightGray").drawCircle(centerX, centerY, radius); stage.addChildAt(bg, 0); createjs.Ticker.timingMode = createjs.Ticker.RAF; }