时间:2021-07-01 10:21:17 帮助过:39人阅读
这是一款基于HTML5的树叶飘落动画,树叶都是图片,并非CSS3绘制,但是树叶飘落的动画效果非常逼真。这款HTML5树叶飘落动画是基于webkit内核的,也就是说要在webkit内核的浏览器上才能使用这款动画。
在线演示源码下载
<p id="container"> <!-- The container is dynamically populated using the init function in leaves.js --> <!-- Its dimensions and position are defined using its id selector in leaves.css --> <p id="leafContainer"></p> <!-- its appearance, dimensions, and position are defined using its id selector in leaves.css --> <p id="message"> <em>这是基于webkit的落叶动画</em> </p> </p>
#container { position: relative; height: 700px; width: 500px; margin: 10px auto; overflow: hidden; border: 4px solid #5C090A; background: #4E4226 url('images/backgroundLeaves.jpg') no-repeat top left; } /* Defines the position and dimensions of the leafContainer p */ #leafContainer { position: absolute; width: 100%; height: 100%; } /* Defines the appearance, position, and dimensions of the message p */ #message { position: absolute; top: 160px; width: 100%; height: 300px; background:transparent url('images/textBackground.png') repeat-x center; color: #5C090A; font-size: 220%; font-family: 'Georgia'; text-align: center; padding: 20px 10px; -webkit-box-sizing: border-box; -webkit-background-size: 100% 100%; z-index: 1; } p { margin: 15px; } a { color: #5C090A; text-decoration: none; } /* Sets the color of the "Dino's Gardening Service" message */ em { font-weight: bold; font-style: normal; } .phone { font-size: 150%; vertical-align: middle; } /* This CSS rule is applied to all p elements in the leafContainer p. It styles and animates each leafp. */ #leafContainer > p { position: absolute; width: 100px; height: 100px; /* We use the following properties to apply the fade and drop animations to each leaf. Each of these properties takes two values. These values respectively match a setting for fade and drop. */ -webkit-animation-iteration-count: infinite, infinite; -webkit-animation-direction: normal, normal; -webkit-animation-timing-function: linear, ease-in; } /* This CSS rule is applied to all img elements directly inside p elements which are directly inside the leafContainer p. In other words, it matches the 'img' elements inside the leafps which are created in the createALeaf() function. */ #leafContainer > p > img { position: absolute; width: 100px; height: 100px; /* We use the following properties to adjust the clockwiseSpin or counterclockwiseSpinAndFlip animations on each leaf. The createALeaf function in the Leaves.js file determines whether a leaf has the clockwiseSpin or counterclockwiseSpinAndFlip animation. */ -webkit-animation-iteration-count: infinite; -webkit-animation-direction: alternate; -webkit-animation-timing-function: ease-in-out; -webkit-transform-origin: 50% -100%; } /* Hides a leaf towards the very end of the animation */ @-webkit-keyframes fade { /* Show a leaf while into or below 95 percent of the animation and hide it, otherwise */ 0% { opacity: 1; } 95% { opacity: 1; } 100% { opacity: 0; } } /* Makes a leaf fall from -300 to 600 pixels in the y-axis */ @-webkit-keyframes drop { /* Move a leaf to -300 pixels in the y-axis at the start of the animation */ 0% { -webkit-transform: translate(0px, -50px); } /* Move a leaf to 600 pixels in the y-axis at the end of the animation */ 100% { -webkit-transform: translate(0px, 650px); } } /* Rotates a leaf from -50 to 50 degrees in 2D space */ @-webkit-keyframes clockwiseSpin { /* Rotate a leaf by -50 degrees in 2D space at the start of the animation */ 0% { -webkit-transform: rotate(-50deg); } /* Rotate a leaf by 50 degrees in 2D space at the end of the animation */ 100% { -webkit-transform: rotate(50deg); } } /* Flips a leaf and rotates it from 50 to -50 degrees in 2D space */ @-webkit-keyframes counterclockwiseSpinAndFlip { /* Flip a leaf and rotate it by 50 degrees in 2D space at the start of the animation */ 0% { -webkit-transform: scale(-1, 1) rotate(50deg); } /* Flip a leaf and rotate it by -50 degrees in 2D space at the end of the animation */ 100% { -webkit-transform: scale(-1, 1) rotate(-50deg); } }
/* Define the number of leaves to be used in the animation */ const NUMBER_OF_LEAVES = 30; /* Called when the "Falling Leaves" page is completely loaded. */ function init() { /* Get a reference to the element that will contain the leaves */ var container = document.getElementById('leafContainer'); /* Fill the empty container with new leaves */ for (var i = 0; i < NUMBER_OF_LEAVES; i++) { container.appendChild(createALeaf()); } } /* Receives the lowest and highest values of a range and returns a random integer that falls within that range. */ function randomInteger(low, high) { return low + Math.floor(Math.random() * (high - low)); } /* Receives the lowest and highest values of a range and returns a random float that falls within that range. */ function randomFloat(low, high) { return low + Math.random() * (high - low); } /* Receives a number and returns its CSS pixel value. */ function pixelValue(value) { return value + 'px'; } /* Returns a duration value for the falling animation. */ function durationValue(value) { return value + 's'; } /* Uses an img element to create each leaf. "Leaves.css" implements two spin animations for the leaves: clockwiseSpin and counterclockwiseSpinAndFlip. This function determines which of these spin animations should be applied to each leaf. */ function createALeaf() { /* Start by creating a wrapper p, and an empty img element */ var leafp = document.createElement('p'); var image = document.createElement('img'); /* Randomly choose a leaf image and assign it to the newly created element */ image.src = 'images/realLeaf' + randomInteger(1, 5) + '.png'; leafp.style.top = "-100px"; /* Position the leaf at a random location along the screen */ leafp.style.left = pixelValue(randomInteger(0, 500)); /* Randomly choose a spin animation */ var spinAnimationName = (Math.random() < 0.5) ? 'clockwiseSpin' : 'counterclockwiseSpinAndFlip'; /* Set the -webkit-animation-name property with these values */ leafp.style.webkitAnimationName = 'fade, drop'; image.style.webkitAnimationName = spinAnimationName; /* Figure out a random duration for the fade and drop animations */ var fadeAndDropDuration = durationValue(randomFloat(5, 11)); /* Figure out another random duration for the spin animation */ var spinDuration = durationValue(randomFloat(4, 8)); /* Set the -webkit-animation-duration property with these values */ leafp.style.webkitAnimationDuration = fadeAndDropDuration + ', ' + fadeAndDropDuration; var leafDelay = durationValue(randomFloat(0, 5)); leafp.style.webkitAnimationDelay = leafDelay + ', ' + leafDelay; image.style.webkitAnimationDuration = spinDuration; // add the <img> to the <p> leafp.appendChild(image); /* Return this img element so it can be added to the document */ return leafp; } /* Calls the init function when the "Falling Leaves" page is full loaded */ window.addEventListener('load', init, false);
以上就是逼真的HTML5树叶飘落动画图文代码详解的内容,更多相关内容请关注PHP中文网(www.gxlcms.com)!