export default { data() { return { canvas: null, ctx: null, arcObj: {} }; }, mounted() { this.canvas = document.getElementById("canvas"); this.ctx = this.canvas.getContext("2d"); // this.move(); // 矩形的边缘碰撞函数 // this.moveArc(); // 绘制碰撞圆形，对象形式 this.moveRect() }, methods: { move() { let x = 0; let y = 0; let width = 100; let height = 100; let speedX = 2; let speedY = 2; let ctx = this.ctx; ctx.fillStyle = "red"; ctx.fillRect(x, y, width, height); setInterval(() => { ctx.clearRect(x, y, this.canvas.width, this.canvas.height); x += speedX; if (x > this.canvas.width - width) { speedX *= -1; } else if (x < 0) { speedX *= -1; } y += speedY; if (y > this.canvas.height - height) { speedY *= -1; } else if (y < 0) { speedY *= -1; } ctx.fillRect(x, y, width, height); }, 10); // this.requestmove(x,y,width,height,ctx,speedX,speedY); // 请求帧的动画过程 }, requestmove(x, y, width, height, ctx, speedX, speedY) { ctx.clearRect(x, y, this.canvas.width, this.canvas.height); x += speedX; if (x > this.canvas.width - width) { speedX *= -1; } else if (x < 0) { speedX *= -1; } y += speedY; if (y > this.canvas.height - height) { speedY *= -1; } else if (y < 0) { speedY *= -1; } ctx.fillRect(x, y, width, height); window.requestAnimationFrame( this.requestmove(x, y, width, height, ctx, speedX, speedY) ); }, moveArc(x, y, r, speedX, speedY) { this.x = x; this.y = y; this.r = r; this.speedX = speedX; this.speedY = speedY; this.moveUpdata = function() { this.x += this.speedX; if (this.x > this.canvas.width - this.r) { this.speedX *= -1; } else if (this.x < 0) { this.speedX *= -1; } this.y += this.speedY; if (this.y > this.canvas.height - this.r) { this.speedY *= -1; } else if (this.y < 0) { this.speedY *= -1; } }; }, moveRect(){ // 面向对象编程 function Rect(x,y,width,height,color,speedX,speedY,ctx,canvas) { this.x = x; this.y = y; this.width = width; this.height = height; this.color = color this.speedX = speedX this.speedY = speedY this.ctxRect = ctx this.canvas = canvas } Rect.prototype.draw = function() { this.ctxRect.beginPath(); this.ctxRect.fillStyle = this.color this.ctxRect.fillRect(this.x,this.y,this.width,this.height) this.ctxRect.closePath(); } Rect.prototype.move = function() { this.x += this.speedX if(this.x > this.canvas.width - this.width){ this.speedX *= -1 } else if(this.x < 0){ this.speedX *= -1 } this.y += this.speedY if(this.y > this.canvas.height - this.height){ this.speedY *= -1 } else if(this.y < 0){ this.speedY *= -1 } } let rect1 = new Rect(0,100,100,100,'red',2,2,this.ctx,this.canvas) let rect2 = new Rect(300,100,100,100,'blue',-2,-2,this.ctx,this.canvas) // rect1.draw(); // rect2.draw() let animate = ()=>{ this.ctx.clearRect(0,0,this.canvas.width,this.canvas.height) rect1.draw() rect1.move() rect2.draw() rect2.move() let rect1Min = rect1.x; let rect1Max = rect1.x + rect1.width let rect2Min = rect2.x let rect2Max = rect2.x + rect2.width let min = Math.max(rect1Min,rect2Min) let max = Math.min(rect1Max,rect2Max) if(min < max){ rect1.speedX *= -1; rect1.speedY *= 1; rect2.speedX *= -1 rect2.speedY *= 1 } window.requestAnimationFrame(animate) } animate() } } };
样式控制
#canvas { border: 1px solid black; }