html - 如何优化 CSS 动画(缩放、旋转、模糊)

Question

下面的 HTML 示例由两张图片组成；一个是背景，另一个是对象。两者都使用缩放和旋转进行动画处理。在全高清显示器上，它往往是不稳定的。当您查看 Firefox 中的性能时，它会达到大约 20 fps。

首先我使用了 jQuery；为了提高性能我选择了 CSS，但它仍然不完美。为了重现问题，请转到全屏。我怎样才能让它变得更好？

.html,
body {
  height: 100%;
  margin: 0;
  padding: 0;
  overflow: hidden;
  background-color: #121212;
}

.maincontainer {
  width: 100%;
  padding-bottom: 100%;
  position: fixed;
  overflow: hidden;
}

.bg {
  background-image: url(http://wallpaper-gallery.net/images/beautiful-pictures-of-nature/beautiful-pictures-of-nature-2.jpg);
  height: 100%;
  width: 100%;
  display: block;
  position: absolute;
  z-index: -99;
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
  background-position: top;
  background-size: 100% auto;
  background-repeat: no-repeat;
}

.bg2 {
  height: 100%;
  width: 100%;
  display: block;
  position: absolute;
  z-index: -99;
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
  background-position: top;
  background-size: 100% auto;
  background-repeat: no-repeat;
}

.rain {
  background-image: url(https://media.giphy.com/media/OvFQrZk8b5N0Q/source.gif);
  height: 100%;
  width: 100%;
  display: block;
  position: absolute;
  z-index: -1;
  -webkit-filter: blur(1px);
}

.animate-bg {
  -webkit-animation-name: animateBg;
  animation-name: animateBg;
}

.animate {
  -webkit-animation-duration: 35000;
  animation-duration: 35000ms;
  -webkit-animation-fill-mode: both;
  animation-fill-mode: both;
  -webkit-animation-timing-function: cubic-bezier(.3, 0, .7, 1);
  animation-timing-function: cubic-bezier(.3, 0, .7, 1);
  animation-iteration-count: infinite;
}


/* Zoom in Keyframes */

@-webkit-keyframes animateBg {
  0% {
    transform: scale(1) rotate(0deg);
  }
  50% {
    transform: scale(1.3) rotate(4deg);
  }
  100% {
    transform: scale(1) rotate(0deg);
  }
}

@keyframes animateBg {
  0% {
    transform: scale(1) rotate(0deg);
  }
  50% {
    transform: scale(1.3) rotate(4deg);
  }
  100% {
    transform: scale(1) rotate(0deg);
  }
}


/*End of Zoom in Keyframes */

.eagle {
  background-image: url(https://pngriver.com/wp-content/uploads/2018/04/Download-Flying-Eagle-PNG-Image.png);
  height: 100%;
  width: 100%;
  display: block;
  position: absolute;
  z-index: 900;
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
  background-position: top;
  background-size: 100% auto;
  background-repeat: no-repeat;
}

.animate-eagle {
  -webkit-animation-duration: 35000;
  animation-duration: 35000ms;
  -webkit-animation-fill-mode: both;
  animation-fill-mode: both;
  -webkit-animation-timing-function: cubic-bezier(.3, 0, .7, 1);
  animation-timing-function: cubic-bezier(.3, 0, .7, 1);
  animation-iteration-count: infinite;
  -webkit-animation-name: animateeagle;
  animation-name: animateeagle;
}


/* Zoom in Keyframes */

@-webkit-keyframes animateeagle {
  0% {
    transform: scale(0.8) rotate(0deg);
  }
  30% {
    transform: scale(1.05) rotate(-2deg);
  }
  50% {
    transform: scale(1.1) rotate(0deg);
  }
  80% {
    transform: scale(1.05) rotate(2deg);
  }
  100% {
    transform: scale(1) rotate(0deg);
  }
}

@keyframes animateeagle {
  0% {
    transform: scale(1) rotate(0deg);
  }
  30% {
    transform: scale(1.05) rotate(-2deg);
  }
  50% {
    transform: scale(1.1) rotate(0deg);
  }
  80% {
    transform: scale(1.05) rotate(2deg);
  }
  100% {
    transform: scale(1) rotate(0deg);
  }
}


/*End of Zoom in Keyframes */

.blur {
  animation: blur 5000ms;
}

@keyframes blur {
  0% {
    -webkit-filter: blur(0px);
  }
  20% {
    -webkit-filter: blur(3px);
  }
  40% {
    -webkit-filter: blur(5px);
  }
  60% {
    -webkit-filter: blur(7px);
  }
  80% {
    -webkit-filter: blur(5px);
  }
  100% {
    -webkit-filter: blur(0px);
  }
}

@-webkit-keyframes blur {
  0% {
    -webkit-filter: blur(0px);
  }
  20% {
    -webkit-filter: blur(3px);
  }
  40% {
    -webkit-filter: blur(5px);
  }
  60% {
    -webkit-filter: blur(7px);
  }
  80% {
    -webkit-filter: blur(5px);
  }
  100% {
    -webkit-filter: blur(0px);
  }
}

.unblur {
  animation: unblur 1000ms;
}

@keyframes unblur {
  0% {
    -webkit-filter: blur(5px);
  }
  100% {
    -webkit-filter: blur(0px);
  }
}

@-webkit-keyframes unblur {
  0% {
    -webkit-filter: blur(5px);
  }
  100% {
    -webkit-filter: blur(0px);
  }
}

<div class="maincontainer">

  <div id="bg2" class="bg2">
    <div id="bg" class="bg animate animate-bg">
      <div class="rain"></div>
      <div class="drops"></div>
    </div>
  </div>

  <div id="eagle">
    <div class="eagle animate-eagle">
    </div>
  </div>
</div>

建议的重复问题不相关，因为我不知道如何用 Canvas 解决这个问题。

Answer 1

看看 will-change 属性，这可能会帮助你让它更平滑一些，你可以阅读它 here

它没有最好的浏览器支持，这是唯一的事情。

我怀疑你在雨中的 1px 模糊可能非常强烈，你正在模糊不断变化的东西。我不太明白您在哪里使用 .blur 类和相关动画，但这对性能来说会非常昂贵。

transform: translate3d(0,0,0); Robert Moore 建议帮助 webkit 特别是使用硬件加速，你可以阅读它 here但是在这种情况下，当您使用过滤器时，它们已经在利用硬件加速