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| − | /** @license
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| − | * DHTML Snowstorm! JavaScript-based snow for web pages
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| − | * Making it snow on the internets since 2003. You're welcome.
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| − | * -----------------------------------------------------------
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| − | * Version 1.44.20131208 (Previous rev: 1.44.20131125)
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| − | * Copyright (c) 2007, Scott Schiller. All rights reserved.
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| − | * Code provided under the BSD License
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| − | * http://schillmania.com/projects/snowstorm/license.txt
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| − | */
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| − |
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| − | /*jslint nomen: true, plusplus: true, sloppy: true, vars: true, white: true */
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| − | /*global window, document, navigator, clearInterval, setInterval */
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| − |
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| − | var snowStorm = (function(window, document) {
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| − |
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| − | // --- common properties ---
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| − |
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| − | this.autoStart = true; // Whether the snow should start automatically or not.
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| − | this.excludeMobile = true; // Snow is likely to be bad news for mobile phones' CPUs (and batteries.) Enable at your own risk.
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| − | this.flakesMax = 128; // Limit total amount of snow made (falling + sticking)
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| − | this.flakesMaxActive = 64; // Limit amount of snow falling at once (less = lower CPU use)
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| − | this.animationInterval = 33; // Theoretical "miliseconds per frame" measurement. 20 = fast + smooth, but high CPU use. 50 = more conservative, but slower
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| − | this.useGPU = true; // Enable transform-based hardware acceleration, reduce CPU load.
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| − | this.className = null; // CSS class name for further customization on snow elements
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| − | this.excludeMobile = false; // Snow is likely to be bad news for mobile phones' CPUs (and batteries.) By default, be nice.
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| − | this.flakeBottom = null; // Integer for Y axis snow limit, 0 or null for "full-screen" snow effect
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| − | this.followMouse = true; // Snow movement can respond to the user's mouse
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| − | this.snowColor = '#fff'; // Don't eat (or use?) yellow snow.
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| − | this.snowCharacter = '•'; // • = bullet, · is square on some systems etc.
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| − | this.snowStick = false; // Whether or not snow should "stick" at the bottom. When off, will never collect.
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| − | this.targetElement = null; // element which snow will be appended to (null = document.body) - can be an element ID eg. 'myDiv', or a DOM node reference
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| − | this.useMeltEffect = true; // When recycling fallen snow (or rarely, when falling), have it "melt" and fade out if browser supports it
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| − | this.useTwinkleEffect = false; // Allow snow to randomly "flicker" in and out of view while falling
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| − | this.usePositionFixed = false; // true = snow does not shift vertically when scrolling. May increase CPU load, disabled by default - if enabled, used only where supported
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| − | this.usePixelPosition = false; // Whether to use pixel values for snow top/left vs. percentages. Auto-enabled if body is position:relative or targetElement is specified.
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| − |
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| − | // --- less-used bits ---
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| − |
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| − | this.freezeOnBlur = true; // Only snow when the window is in focus (foreground.) Saves CPU.
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| − | this.flakeLeftOffset = 0; // Left margin/gutter space on edge of container (eg. browser window.) Bump up these values if seeing horizontal scrollbars.
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| − | this.flakeRightOffset = 0; // Right margin/gutter space on edge of container
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| − | this.flakeWidth = 8; // Max pixel width reserved for snow element
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| − | this.flakeHeight = 8; // Max pixel height reserved for snow element
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| − | this.vMaxX = 5; // Maximum X velocity range for snow
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| − | this.vMaxY = 4; // Maximum Y velocity range for snow
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| − | this.zIndex = 7000; // CSS stacking order applied to each snowflake
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| − |
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| − | // --- "No user-serviceable parts inside" past this point, yadda yadda ---
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| − |
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| − | var storm = this,
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| − | features,
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| − | // UA sniffing and backCompat rendering mode checks for fixed position, etc.
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| − | isIE = navigator.userAgent.match(/msie/i),
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| − | isIE6 = navigator.userAgent.match(/msie 6/i),
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| − | isMobile = navigator.userAgent.match(/mobile|opera m(ob|in)/i),
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| − | isBackCompatIE = (isIE && document.compatMode === 'BackCompat'),
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| − | noFixed = (isBackCompatIE || isIE6),
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| − | screenX = null, screenX2 = null, screenY = null, scrollY = null, docHeight = null, vRndX = null, vRndY = null,
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| − | windOffset = 1,
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| − | windMultiplier = 2,
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| − | flakeTypes = 6,
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| − | fixedForEverything = false,
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| − | targetElementIsRelative = false,
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| − | opacitySupported = (function(){
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| − | try {
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| − | document.createElement('div').style.opacity = '0.5';
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| − | } catch(e) {
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| − | return false;
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| − | }
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| − | return true;
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| − | }()),
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| − | didInit = false,
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| − | docFrag = document.createDocumentFragment();
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| − |
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| − | features = (function() {
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| − |
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| − | var getAnimationFrame;
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| − |
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| − | /**
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| − | * hat tip: paul irish
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| − | * http://paulirish.com/2011/requestanimationframe-for-smart-animating/
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| − | * https://gist.github.com/838785
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| − | */
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| − |
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| − | function timeoutShim(callback) {
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| − | window.setTimeout(callback, 1000/(storm.animationInterval || 20));
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| − | }
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| − |
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| − | var _animationFrame = (window.requestAnimationFrame ||
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| − | window.webkitRequestAnimationFrame ||
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| − | window.mozRequestAnimationFrame ||
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| − | window.oRequestAnimationFrame ||
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| − | window.msRequestAnimationFrame ||
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| − | timeoutShim);
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| − |
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| − | // apply to window, avoid "illegal invocation" errors in Chrome
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| − | getAnimationFrame = _animationFrame ? function() {
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| − | return _animationFrame.apply(window, arguments);
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| − | } : null;
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| − |
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| − | var testDiv;
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| − |
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| − | testDiv = document.createElement('div');
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| − |
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| − | function has(prop) {
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| − |
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| − | // test for feature support
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| − | var result = testDiv.style[prop];
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| − | return (result !== undefined ? prop : null);
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| − |
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| − | }
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| − |
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| − | // note local scope.
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| − | var localFeatures = {
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| − |
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| − | transform: {
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| − | ie: has('-ms-transform'),
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| − | moz: has('MozTransform'),
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| − | opera: has('OTransform'),
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| − | webkit: has('webkitTransform'),
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| − | w3: has('transform'),
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| − | prop: null // the normalized property value
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| − | },
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| − |
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| − | getAnimationFrame: getAnimationFrame
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| − |
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| − | };
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| − |
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| − | localFeatures.transform.prop = (
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| − | localFeatures.transform.w3 ||
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| − | localFeatures.transform.moz ||
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| − | localFeatures.transform.webkit ||
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| − | localFeatures.transform.ie ||
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| − | localFeatures.transform.opera
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| − | );
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| − |
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| − | testDiv = null;
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| − |
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| − | return localFeatures;
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| − |
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| − | }());
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| − |
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| − | this.timer = null;
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| − | this.flakes = [];
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| − | this.disabled = false;
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| − | this.active = false;
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| − | this.meltFrameCount = 20;
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| − | this.meltFrames = [];
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| − |
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| − | this.setXY = function(o, x, y) {
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| − |
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| − | if (!o) {
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| − | return false;
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| − | }
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| − |
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| − | if (storm.usePixelPosition || targetElementIsRelative) {
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| − |
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| − | o.style.left = (x - storm.flakeWidth) + 'px';
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| − | o.style.top = (y - storm.flakeHeight) + 'px';
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| − |
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| − | } else if (noFixed) {
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| − |
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| − | o.style.right = (100-(x/screenX*100)) + '%';
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| − | // avoid creating vertical scrollbars
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| − | o.style.top = (Math.min(y, docHeight-storm.flakeHeight)) + 'px';
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| − |
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| − | } else {
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| − |
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| − | if (!storm.flakeBottom) {
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| − |
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| − | // if not using a fixed bottom coordinate...
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| − | o.style.right = (100-(x/screenX*100)) + '%';
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| − | o.style.bottom = (100-(y/screenY*100)) + '%';
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| − |
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| − | } else {
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| − |
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| − | // absolute top.
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| − | o.style.right = (100-(x/screenX*100)) + '%';
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| − | o.style.top = (Math.min(y, docHeight-storm.flakeHeight)) + 'px';
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| − |
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| − | }
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| − |
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| − | }
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| − |
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| − | };
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| − |
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| − | this.events = (function() {
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| − |
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| − | var old = (!window.addEventListener && window.attachEvent), slice = Array.prototype.slice,
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| − | evt = {
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| − | add: (old?'attachEvent':'addEventListener'),
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| − | remove: (old?'detachEvent':'removeEventListener')
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| − | };
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| − |
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| − | function getArgs(oArgs) {
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| − | var args = slice.call(oArgs), len = args.length;
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| − | if (old) {
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| − | args[1] = 'on' + args[1]; // prefix
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| − | if (len > 3) {
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| − | args.pop(); // no capture
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| − | }
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| − | } else if (len === 3) {
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| − | args.push(false);
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| − | }
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| − | return args;
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| − | }
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| − |
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| − | function apply(args, sType) {
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| − | var element = args.shift(),
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| − | method = [evt[sType]];
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| − | if (old) {
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| − | element[method](args[0], args[1]);
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| − | } else {
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| − | element[method].apply(element, args);
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| − | }
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| − | }
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| − |
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| − | function addEvent() {
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| − | apply(getArgs(arguments), 'add');
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| − | }
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| − |
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| − | function removeEvent() {
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| − | apply(getArgs(arguments), 'remove');
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| − | }
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| − |
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| − | return {
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| − | add: addEvent,
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| − | remove: removeEvent
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| − | };
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| − |
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| − | }());
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| − |
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| − | function rnd(n,min) {
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| − | if (isNaN(min)) {
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| − | min = 0;
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| − | }
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| − | return (Math.random()*n)+min;
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| − | }
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| − |
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| − | function plusMinus(n) {
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| − | return (parseInt(rnd(2),10)===1?n*-1:n);
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| − | }
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| − |
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| − | this.randomizeWind = function() {
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| − | var i;
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| − | vRndX = plusMinus(rnd(storm.vMaxX,0.2));
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| − | vRndY = rnd(storm.vMaxY,0.2);
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| − | if (this.flakes) {
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| − | for (i=0; i<this.flakes.length; i++) {
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| − | if (this.flakes[i].active) {
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| − | this.flakes[i].setVelocities();
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| − | }
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| − | }
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| − | }
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| − | };
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| − |
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| − | this.scrollHandler = function() {
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| − | var i;
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| − | // "attach" snowflakes to bottom of window if no absolute bottom value was given
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| − | scrollY = (storm.flakeBottom ? 0 : parseInt(window.scrollY || document.documentElement.scrollTop || (noFixed ? document.body.scrollTop : 0), 10));
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| − | if (isNaN(scrollY)) {
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| − | scrollY = 0; // Netscape 6 scroll fix
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| − | }
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| − | if (!fixedForEverything && !storm.flakeBottom && storm.flakes) {
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| − | for (i=0; i<storm.flakes.length; i++) {
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| − | if (storm.flakes[i].active === 0) {
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| − | storm.flakes[i].stick();
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| − | }
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| − | }
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| − | }
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| − | };
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| − |
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| − | this.resizeHandler = function() {
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| − | if (window.innerWidth || window.innerHeight) {
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| − | screenX = window.innerWidth - 16 - storm.flakeRightOffset;
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| − | screenY = (storm.flakeBottom || window.innerHeight);
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| − | } else {
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| − | screenX = (document.documentElement.clientWidth || document.body.clientWidth || document.body.scrollWidth) - (!isIE ? 8 : 0) - storm.flakeRightOffset;
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| − | screenY = storm.flakeBottom || document.documentElement.clientHeight || document.body.clientHeight || document.body.scrollHeight;
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| − | }
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| − | docHeight = document.body.offsetHeight;
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| − | screenX2 = parseInt(screenX/2,10);
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| − | };
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| − |
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| − | this.resizeHandlerAlt = function() {
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| − | screenX = storm.targetElement.offsetWidth - storm.flakeRightOffset;
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| − | screenY = storm.flakeBottom || storm.targetElement.offsetHeight;
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| − | screenX2 = parseInt(screenX/2,10);
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| − | docHeight = document.body.offsetHeight;
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| − | };
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| − |
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| − | this.freeze = function() {
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| − | // pause animation
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| − | if (!storm.disabled) {
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| − | storm.disabled = 1;
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| − | } else {
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| − | return false;
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| − | }
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| − | storm.timer = null;
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| − | };
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| − |
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| − | this.resume = function() {
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| − | if (storm.disabled) {
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| − | storm.disabled = 0;
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| − | } else {
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| − | return false;
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| − | }
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| − | storm.timerInit();
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| − | };
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| − |
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| − | this.toggleSnow = function() {
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| − | if (!storm.flakes.length) {
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| − | // first run
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| − | storm.start();
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| − | } else {
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| − | storm.active = !storm.active;
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| − | if (storm.active) {
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| − | storm.show();
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| − | storm.resume();
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| − | } else {
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| − | storm.stop();
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| − | storm.freeze();
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| − | }
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| − | }
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| − | };
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| − |
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| − | this.stop = function() {
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| − | var i;
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| − | this.freeze();
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| − | for (i=0; i<this.flakes.length; i++) {
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| − | this.flakes[i].o.style.display = 'none';
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| − | }
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| − | storm.events.remove(window,'scroll',storm.scrollHandler);
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| − | storm.events.remove(window,'resize',storm.resizeHandler);
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| − | if (storm.freezeOnBlur) {
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| − | if (isIE) {
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| − | storm.events.remove(document,'focusout',storm.freeze);
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| − | storm.events.remove(document,'focusin',storm.resume);
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| − | } else {
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| − | storm.events.remove(window,'blur',storm.freeze);
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| − | storm.events.remove(window,'focus',storm.resume);
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| − | }
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| − | }
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| − | };
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| − |
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| − | this.show = function() {
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| − | var i;
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| − | for (i=0; i<this.flakes.length; i++) {
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| − | this.flakes[i].o.style.display = 'block';
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| − | }
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| − | };
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| − |
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| − | this.SnowFlake = function(type,x,y) {
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| − | var s = this;
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| − | this.type = type;
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| − | this.x = x||parseInt(rnd(screenX-20),10);
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| − | this.y = (!isNaN(y)?y:-rnd(screenY)-12);
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| − | this.vX = null;
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| − | this.vY = null;
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| − | this.vAmpTypes = [1,1.2,1.4,1.6,1.8]; // "amplification" for vX/vY (based on flake size/type)
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| − | this.vAmp = this.vAmpTypes[this.type] || 1;
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| − | this.melting = false;
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| − | this.meltFrameCount = storm.meltFrameCount;
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| − | this.meltFrames = storm.meltFrames;
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| − | this.meltFrame = 0;
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| − | this.twinkleFrame = 0;
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| − | this.active = 1;
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| − | this.fontSize = (10+(this.type/5)*10);
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| − | this.o = document.createElement('div');
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| − | this.o.innerHTML = storm.snowCharacter;
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| − | if (storm.className) {
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| − | this.o.setAttribute('class', storm.className);
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| − | }
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| − | this.o.style.color = storm.snowColor;
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| − | this.o.style.position = (fixedForEverything?'fixed':'absolute');
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| − | if (storm.useGPU && features.transform.prop) {
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| − | // GPU-accelerated snow.
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| − | this.o.style[features.transform.prop] = 'translate3d(0px, 0px, 0px)';
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| − | }
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| − | this.o.style.width = storm.flakeWidth+'px';
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| − | this.o.style.height = storm.flakeHeight+'px';
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| − | this.o.style.fontFamily = 'arial,verdana';
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| − | this.o.style.cursor = 'default';
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| − | this.o.style.overflow = 'hidden';
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| − | this.o.style.fontWeight = 'normal';
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| − | this.o.style.zIndex = storm.zIndex;
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| − | docFrag.appendChild(this.o);
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| − |
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| − | this.refresh = function() {
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| − | if (isNaN(s.x) || isNaN(s.y)) {
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| − | // safety check
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| − | return false;
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| − | }
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| − | storm.setXY(s.o, s.x, s.y);
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| − | };
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| − |
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| − | this.stick = function() {
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| − | if (noFixed || (storm.targetElement !== document.documentElement && storm.targetElement !== document.body)) {
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| − | s.o.style.top = (screenY+scrollY-storm.flakeHeight)+'px';
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| − | } else if (storm.flakeBottom) {
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| − | s.o.style.top = storm.flakeBottom+'px';
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| − | } else {
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| − | s.o.style.display = 'none';
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| − | s.o.style.bottom = '0%';
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| − | s.o.style.position = 'fixed';
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| − | s.o.style.display = 'block';
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| − | }
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| − | };
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| − |
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| − | this.vCheck = function() {
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| − | if (s.vX>=0 && s.vX<0.2) {
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| − | s.vX = 0.2;
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| − | } else if (s.vX<0 && s.vX>-0.2) {
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| − | s.vX = -0.2;
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| − | }
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| − | if (s.vY>=0 && s.vY<0.2) {
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| − | s.vY = 0.2;
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| − | }
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| − | };
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| − |
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| − | this.move = function() {
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| − | var vX = s.vX*windOffset, yDiff;
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| − | s.x += vX;
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| − | s.y += (s.vY*s.vAmp);
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| − | if (s.x >= screenX || screenX-s.x < storm.flakeWidth) { // X-axis scroll check
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| − | s.x = 0;
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| − | } else if (vX < 0 && s.x-storm.flakeLeftOffset < -storm.flakeWidth) {
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| − | s.x = screenX-storm.flakeWidth-1; // flakeWidth;
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| − | }
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| − | s.refresh();
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| − | yDiff = screenY+scrollY-s.y+storm.flakeHeight;
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| − | if (yDiff<storm.flakeHeight) {
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| − | s.active = 0;
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| − | if (storm.snowStick) {
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| − | s.stick();
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| − | } else {
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| − | s.recycle();
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| − | }
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| − | } else {
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| − | if (storm.useMeltEffect && s.active && s.type < 3 && !s.melting && Math.random()>0.998) {
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| − | // ~1/1000 chance of melting mid-air, with each frame
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| − | s.melting = true;
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| − | s.melt();
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| − | // only incrementally melt one frame
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| − | // s.melting = false;
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| − | }
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| − | if (storm.useTwinkleEffect) {
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| − | if (s.twinkleFrame < 0) {
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| − | if (Math.random() > 0.97) {
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| − | s.twinkleFrame = parseInt(Math.random() * 8, 10);
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| − | }
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| − | } else {
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| − | s.twinkleFrame--;
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| − | if (!opacitySupported) {
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| − | s.o.style.visibility = (s.twinkleFrame && s.twinkleFrame % 2 === 0 ? 'hidden' : 'visible');
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| − | } else {
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| − | s.o.style.opacity = (s.twinkleFrame && s.twinkleFrame % 2 === 0 ? 0 : 1);
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| − | }
| |
| − | }
| |
| − | }
| |
| − | }
| |
| − | };
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| − |
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| − | this.animate = function() {
| |
| − | // main animation loop
| |
| − | // move, check status, die etc.
| |
| − | s.move();
| |
| − | };
| |
| − |
| |
| − | this.setVelocities = function() {
| |
| − | s.vX = vRndX+rnd(storm.vMaxX*0.12,0.1);
| |
| − | s.vY = vRndY+rnd(storm.vMaxY*0.12,0.1);
| |
| − | };
| |
| − |
| |
| − | this.setOpacity = function(o,opacity) {
| |
| − | if (!opacitySupported) {
| |
| − | return false;
| |
| − | }
| |
| − | o.style.opacity = opacity;
| |
| − | };
| |
| − |
| |
| − | this.melt = function() {
| |
| − | if (!storm.useMeltEffect || !s.melting) {
| |
| − | s.recycle();
| |
| − | } else {
| |
| − | if (s.meltFrame < s.meltFrameCount) {
| |
| − | s.setOpacity(s.o,s.meltFrames[s.meltFrame]);
| |
| − | s.o.style.fontSize = s.fontSize-(s.fontSize*(s.meltFrame/s.meltFrameCount))+'px';
| |
| − | s.o.style.lineHeight = storm.flakeHeight+2+(storm.flakeHeight*0.75*(s.meltFrame/s.meltFrameCount))+'px';
| |
| − | s.meltFrame++;
| |
| − | } else {
| |
| − | s.recycle();
| |
| − | }
| |
| − | }
| |
| − | };
| |
| − |
| |
| − | this.recycle = function() {
| |
| − | s.o.style.display = 'none';
| |
| − | s.o.style.position = (fixedForEverything?'fixed':'absolute');
| |
| − | s.o.style.bottom = 'auto';
| |
| − | s.setVelocities();
| |
| − | s.vCheck();
| |
| − | s.meltFrame = 0;
| |
| − | s.melting = false;
| |
| − | s.setOpacity(s.o,1);
| |
| − | s.o.style.padding = '0px';
| |
| − | s.o.style.margin = '0px';
| |
| − | s.o.style.fontSize = s.fontSize+'px';
| |
| − | s.o.style.lineHeight = (storm.flakeHeight+2)+'px';
| |
| − | s.o.style.textAlign = 'center';
| |
| − | s.o.style.verticalAlign = 'baseline';
| |
| − | s.x = parseInt(rnd(screenX-storm.flakeWidth-20),10);
| |
| − | s.y = parseInt(rnd(screenY)*-1,10)-storm.flakeHeight;
| |
| − | s.refresh();
| |
| − | s.o.style.display = 'block';
| |
| − | s.active = 1;
| |
| − | };
| |
| − |
| |
| − | this.recycle(); // set up x/y coords etc.
| |
| − | this.refresh();
| |
| − |
| |
| − | };
| |
| − |
| |
| − | this.snow = function() {
| |
| − | var active = 0, flake = null, i, j;
| |
| − | for (i=0, j=storm.flakes.length; i<j; i++) {
| |
| − | if (storm.flakes[i].active === 1) {
| |
| − | storm.flakes[i].move();
| |
| − | active++;
| |
| − | }
| |
| − | if (storm.flakes[i].melting) {
| |
| − | storm.flakes[i].melt();
| |
| − | }
| |
| − | }
| |
| − | if (active<storm.flakesMaxActive) {
| |
| − | flake = storm.flakes[parseInt(rnd(storm.flakes.length),10)];
| |
| − | if (flake.active === 0) {
| |
| − | flake.melting = true;
| |
| − | }
| |
| − | }
| |
| − | if (storm.timer) {
| |
| − | features.getAnimationFrame(storm.snow);
| |
| − | }
| |
| − | };
| |
| − |
| |
| − | this.mouseMove = function(e) {
| |
| − | if (!storm.followMouse) {
| |
| − | return true;
| |
| − | }
| |
| − | var x = parseInt(e.clientX,10);
| |
| − | if (x<screenX2) {
| |
| − | windOffset = -windMultiplier+(x/screenX2*windMultiplier);
| |
| − | } else {
| |
| − | x -= screenX2;
| |
| − | windOffset = (x/screenX2)*windMultiplier;
| |
| − | }
| |
| − | };
| |
| − |
| |
| − | this.createSnow = function(limit,allowInactive) {
| |
| − | var i;
| |
| − | for (i=0; i<limit; i++) {
| |
| − | storm.flakes[storm.flakes.length] = new storm.SnowFlake(parseInt(rnd(flakeTypes),10));
| |
| − | if (allowInactive || i>storm.flakesMaxActive) {
| |
| − | storm.flakes[storm.flakes.length-1].active = -1;
| |
| − | }
| |
| − | }
| |
| − | storm.targetElement.appendChild(docFrag);
| |
| − | };
| |
| − |
| |
| − | this.timerInit = function() {
| |
| − | storm.timer = true;
| |
| − | storm.snow();
| |
| − | };
| |
| − |
| |
| − | this.init = function() {
| |
| − | var i;
| |
| − | for (i=0; i<storm.meltFrameCount; i++) {
| |
| − | storm.meltFrames.push(1-(i/storm.meltFrameCount));
| |
| − | }
| |
| − | storm.randomizeWind();
| |
| − | storm.createSnow(storm.flakesMax); // create initial batch
| |
| − | storm.events.add(window,'resize',storm.resizeHandler);
| |
| − | storm.events.add(window,'scroll',storm.scrollHandler);
| |
| − | if (storm.freezeOnBlur) {
| |
| − | if (isIE) {
| |
| − | storm.events.add(document,'focusout',storm.freeze);
| |
| − | storm.events.add(document,'focusin',storm.resume);
| |
| − | } else {
| |
| − | storm.events.add(window,'blur',storm.freeze);
| |
| − | storm.events.add(window,'focus',storm.resume);
| |
| − | }
| |
| − | }
| |
| − | storm.resizeHandler();
| |
| − | storm.scrollHandler();
| |
| − | if (storm.followMouse) {
| |
| − | storm.events.add(isIE?document:window,'mousemove',storm.mouseMove);
| |
| − | }
| |
| − | storm.animationInterval = Math.max(20,storm.animationInterval);
| |
| − | storm.timerInit();
| |
| − | };
| |
| − |
| |
| − | this.start = function(bFromOnLoad) {
| |
| − | if (!didInit) {
| |
| − | didInit = true;
| |
| − | } else if (bFromOnLoad) {
| |
| − | // already loaded and running
| |
| − | return true;
| |
| − | }
| |
| − | if (typeof storm.targetElement === 'string') {
| |
| − | var targetID = storm.targetElement;
| |
| − | storm.targetElement = document.getElementById(targetID);
| |
| − | if (!storm.targetElement) {
| |
| − | throw new Error('Snowstorm: Unable to get targetElement "'+targetID+'"');
| |
| − | }
| |
| − | }
| |
| − | if (!storm.targetElement) {
| |
| − | storm.targetElement = (document.body || document.documentElement);
| |
| − | }
| |
| − | if (storm.targetElement !== document.documentElement && storm.targetElement !== document.body) {
| |
| − | // re-map handler to get element instead of screen dimensions
| |
| − | storm.resizeHandler = storm.resizeHandlerAlt;
| |
| − | //and force-enable pixel positioning
| |
| − | storm.usePixelPosition = true;
| |
| − | }
| |
| − | storm.resizeHandler(); // get bounding box elements
| |
| − | storm.usePositionFixed = (storm.usePositionFixed && !noFixed && !storm.flakeBottom); // whether or not position:fixed is to be used
| |
| − | if (window.getComputedStyle) {
| |
| − | // attempt to determine if body or user-specified snow parent element is relatlively-positioned.
| |
| − | try {
| |
| − | targetElementIsRelative = (window.getComputedStyle(storm.targetElement, null).getPropertyValue('position') === 'relative');
| |
| − | } catch(e) {
| |
| − | // oh well
| |
| − | targetElementIsRelative = false;
| |
| − | }
| |
| − | }
| |
| − | fixedForEverything = storm.usePositionFixed;
| |
| − | if (screenX && screenY && !storm.disabled) {
| |
| − | storm.init();
| |
| − | storm.active = true;
| |
| − | }
| |
| − | };
| |
| − |
| |
| − | function doDelayedStart() {
| |
| − | window.setTimeout(function() {
| |
| − | storm.start(true);
| |
| − | }, 20);
| |
| − | // event cleanup
| |
| − | storm.events.remove(isIE?document:window,'mousemove',doDelayedStart);
| |
| − | }
| |
| − |
| |
| − | function doStart() {
| |
| − | if (!storm.excludeMobile || !isMobile) {
| |
| − | doDelayedStart();
| |
| − | }
| |
| − | // event cleanup
| |
| − | storm.events.remove(window, 'load', doStart);
| |
| − | }
| |
| − |
| |
| − | // hooks for starting the snow
| |
| − | if (storm.autoStart) {
| |
| − | storm.events.add(window, 'load', doStart, false);
| |
| − | }
| |
| − |
| |
| − | return this;
| |
| − |
| |
| − | }(window, document));
| |
| | | | |
| | /* Any JavaScript here will be loaded for all users on every page load. */ | | /* Any JavaScript here will be loaded for all users on every page load. */ |
