html火焰文字特效

下面是代码：

<!DOCTYPE html>
<html><head><meta charset="UTF-8"><title>HTML5火焰文字特效DEMO演示</title><link rel="stylesheet" href="css/style.css" media="screen" type="text/css" /></head><body>
<div style="text-align:center;clear:both;position:absolute;top:10px;left:260px;z-index:999">
<script src="/gg_bd_ad_720x90.js" type="text/javascript"></script>
<script src="/follow.js" type="text/javascript"></script>
</div><div id="canvasContainer"></div><span id="textInputSpan">Your name (max 10 chars) :<input id="textInput" maxlength="10" type="text" width="150" /><button onclick="changeText()">GO!</button>
</span><script src="js/index.js"></script></body></html>

style.css：

html, body{margin : 0px;width : 100%;height : 100%;overflow: hidden;background-color: #000000;font-family: sans-serif;
}#canvasContainer{margin : 0px;width : 100%;height : 100%;
}#textInputSpan{position: absolute;color: #FFFFFF;font-family: sans-serif;
}

index.js：

/** Stats.js 1.1* http://code.google.com/p/mrdoob/wiki/stats_js**/function Stats()
{this.init();
}Stats.prototype ={init: function(){this.frames = 0;this.framesMin = 100;this.framesMax = 0;this.time = new Date().getTime();this.timePrev = new Date().getTime();this.container = document.createElement("div");this.container.style.position = 'absolute';this.container.style.fontFamily = 'Arial';this.container.style.fontSize = '10px';this.container.style.backgroundColor = '#000020';this.container.style.opacity = '0.9';this.container.style.width = '80px';this.container.style.paddingTop = '2px';this.framesText = document.createElement("div");this.framesText.style.color = '#00ffff';this.framesText.style.marginLeft = '3px';this.framesText.style.marginBottom = '3px';this.framesText.innerHTML = '<strong>FPS</strong>';this.container.appendChild(this.framesText);this.canvas = document.createElement("canvas");this.canvas.width = 74;this.canvas.height = 30;this.canvas.style.display = 'block';this.canvas.style.marginLeft = '3px';this.canvas.style.marginBottom = '3px';this.container.appendChild(this.canvas);this.context = this.canvas.getContext("2d");this.context.fillStyle = '#101030';this.context.fillRect(0, 0, this.canvas.width, this.canvas.height );this.contextImageData = this.context.getImageData(0, 0, this.canvas.width, this.canvas.height);setInterval( bargs( function( _this ) { _this.update(); return false; }, this ), 1000 );},getDisplayElement: function(){return this.container;},tick: function(){this.frames++;},update: function(){this.time = new Date().getTime();this.fps = Math.round((this.frames * 1000 ) / (this.time - this.timePrev)); //.toPrecision(2);this.framesMin = Math.min(this.framesMin, this.fps);this.framesMax = Math.max(this.framesMax, this.fps);this.framesText.innerHTML = '<strong>' + this.fps + ' FPS</strong> (' + this.framesMin + '-' + this.framesMax + ')';this.contextImageData = this.context.getImageData(1, 0, this.canvas.width - 1, 30);this.context.putImageData(this.contextImageData, 0, 0);this.context.fillStyle = '#101030';this.context.fillRect(this.canvas.width - 1, 0, 1, 30);this.index = ( Math.floor(30 - Math.min(30, (this.fps / 60) * 30)) );this.context.fillStyle = '#80ffff';this.context.fillRect(this.canvas.width - 1, this.index, 1, 1);this.context.fillStyle = '#00ffff';this.context.fillRect(this.canvas.width - 1, this.index + 1, 1, 30 - this.index);this.timePrev = this.time;this.frames = 0;}
}// Hack by Spitefunction bargs( _fn )
{var args = [];for( var n = 1; n < arguments.length; n++ )args.push( arguments[ n ] );return function () { return _fn.apply( this, args ); };
}(function (window){var Sakri = window.Sakri || {};window.Sakri = window.Sakri || Sakri;Sakri.MathUtil = {};//return number between 1 and 0Sakri.MathUtil.normalize = function(value, minimum, maximum){return (value - minimum) / (maximum - minimum);};//map normalized number to valuesSakri.MathUtil.interpolate = function(normValue, minimum, maximum){return minimum + (maximum - minimum) * normValue;};//map a value from one set to anotherSakri.MathUtil.map = function(value, min1, max1, min2, max2){return Sakri.MathUtil.interpolate( Sakri.MathUtil.normalize(value, min1, max1), min2, max2);};Sakri.MathUtil.hexToRgb = function(hex) {// Expand shorthand form (e.g. "03F") to full form (e.g. "0033FF")var shorthandRegex = /^#?([a-f\d])([a-f\d])([a-f\d])$/i;hex = hex.replace(shorthandRegex, function(m, r, g, b) {return r + r + g + g + b + b;});var result = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i.exec(hex);return result ? {r: parseInt(result[1], 16),g: parseInt(result[2], 16),b: parseInt(result[3], 16)} : null;}Sakri.MathUtil.getRandomNumberInRange = function(min, max){return min + Math.random() * (max - min);};Sakri.MathUtil.getRandomIntegerInRange = function(min, max){return Math.round(Sakri.MathUtil.getRandomNumberInRange(min, max));};}(window));//has a dependency on Sakri.MathUtil(function (window){var Sakri = window.Sakri || {};window.Sakri = window.Sakri || Sakri;Sakri.Geom = {};//==================================================//=====================::POINT::====================//==================================================Sakri.Geom.Point = function (x,y){this.x = isNaN(x) ? 0 : x;this.y = isNaN(y) ? 0 : y;};Sakri.Geom.Point.prototype.clone = function(){return new Sakri.Geom.Point(this.x,this.y);};Sakri.Geom.Point.prototype.update = function(x, y){this.x = isNaN(x) ? this.x : x;this.y = isNaN(y) ? this.y : y;};//==================================================//===================::RECTANGLE::==================//==================================================Sakri.Geom.Rectangle = function (x, y, width, height){this.update(x, y, width, height);};Sakri.Geom.Rectangle.prototype.update = function(x, y, width, height){this.x = isNaN(x) ? 0 : x;this.y = isNaN(y) ? 0 : y;this.width = isNaN(width) ? 0 : width;this.height = isNaN(height) ? 0 : height;};Sakri.Geom.Rectangle.prototype.getRight = function(){return this.x + this.width;};Sakri.Geom.Rectangle.prototype.getBottom = function(){return this.y + this.height;};Sakri.Geom.Rectangle.prototype.getCenter = function(){return new Sakri.Geom.Point(this.getCenterX(), this.getCenterY());};Sakri.Geom.Rectangle.prototype.getCenterX = function(){return this.x + this.width/2;};Sakri.Geom.Rectangle.prototype.getCenterY=function(){return this.y + this.height/2;};Sakri.Geom.Rectangle.prototype.containsPoint = function(x, y){return x >= this.x && y >= this.y && x <= this.getRight() && y <= this.getBottom();};Sakri.Geom.Rectangle.prototype.clone = function(){return new Sakri.Geom.Rectangle(this.x, this.y, this.width, this.height);};Sakri.Geom.Rectangle.prototype.toString = function(){return "Rectangle{x:"+this.x+" , y:"+this.y+" , width:"+this.width+" , height:"+this.height+"}";};}(window));/*** Created by sakri on 27-1-14.* has a dependecy on Sakri.Geom* has a dependecy on Sakri.BitmapUtil*/(function (window){var Sakri = window.Sakri || {};window.Sakri = window.Sakri || Sakri;Sakri.CanvasTextUtil = {};//returns the biggest font size that best fits into given widthSakri.CanvasTextUtil.getFontSizeForWidth = function(string, fontProps, width, canvas, fillStyle, maxFontSize){if(!canvas){var canvas = document.createElement("canvas");}if(!fillStyle){fillStyle = "#000000";}if(isNaN(maxFontSize)){maxFontSize = 500;}var context = canvas.getContext('2d');context.font = fontProps.getFontString();context.textBaseline = "top";var copy = fontProps.clone();//console.log("getFontSizeForWidth() 1  : ", copy.fontSize);context.font = copy.getFontString();var textWidth = context.measureText(string).width;//SOME DISAGREEMENT WHETHER THIS SHOOULD BE WITH && or ||if(textWidth < width){while(context.measureText(string).width < width){copy.fontSize++;context.font = copy.getFontString();if(copy.fontSize > maxFontSize){console.log("getFontSizeForWidth() max fontsize reached");return null;}}}else if(textWidth > width){while(context.measureText(string).width > width){copy.fontSize--;context.font = copy.getFontString();if(copy.fontSize < 0){console.log("getFontSizeForWidth() min fontsize reached");return null;}}}//console.log("getFontSizeForWidth() 2  : ", copy.fontSize);return copy.fontSize;};//=========================================================================================//==============::CANVAS TEXT PROPERTIES::====================================//========================================================Sakri.CanvasTextProperties = function(fontWeight, fontStyle, fontSize, fontFace){this.setFontWeight(fontWeight);this.setFontStyle(fontStyle);this.setFontSize(fontSize);this.fontFace = fontFace ? fontFace : "sans-serif";};Sakri.CanvasTextProperties.NORMAL = "normal";Sakri.CanvasTextProperties.BOLD = "bold";Sakri.CanvasTextProperties.BOLDER = "bolder";Sakri.CanvasTextProperties.LIGHTER = "lighter";Sakri.CanvasTextProperties.ITALIC = "italic";Sakri.CanvasTextProperties.OBLIQUE = "oblique";Sakri.CanvasTextProperties.prototype.setFontWeight = function(fontWeight){switch (fontWeight){case Sakri.CanvasTextProperties.NORMAL:case Sakri.CanvasTextProperties.BOLD:case Sakri.CanvasTextProperties.BOLDER:case Sakri.CanvasTextProperties.LIGHTER:this.fontWeight = fontWeight;break;default:this.fontWeight = Sakri.CanvasTextProperties.NORMAL;}};Sakri.CanvasTextProperties.prototype.setFontStyle = function(fontStyle){switch (fontStyle){case Sakri.CanvasTextProperties.NORMAL:case Sakri.CanvasTextProperties.ITALIC:case Sakri.CanvasTextProperties.OBLIQUE:this.fontStyle = fontStyle;break;default:this.fontStyle = Sakri.CanvasTextProperties.NORMAL;}};Sakri.CanvasTextProperties.prototype.setFontSize = function(fontSize){if(fontSize && fontSize.indexOf && fontSize.indexOf("px")>-1){var size = fontSize.split("px")[0];fontProperites.fontSize = isNaN(size) ? 24 : size;//24 is just an arbitrary numberreturn;}this.fontSize = isNaN(fontSize) ? 24 : fontSize;//24 is just an arbitrary number};Sakri.CanvasTextProperties.prototype.clone = function(){return new Sakri.CanvasTextProperties(this.fontWeight, this.fontStyle, this.fontSize, this.fontFace);};Sakri.CanvasTextProperties.prototype.getFontString = function(){return this.fontWeight + " " + this.fontStyle + " " + this.fontSize + "px " + this.fontFace;};}(window));window.requestAnimationFrame =window.__requestAnimationFrame ||window.requestAnimationFrame ||window.webkitRequestAnimationFrame ||window.mozRequestAnimationFrame ||window.oRequestAnimationFrame ||window.msRequestAnimationFrame ||(function () {return function (callback, element) {var lastTime = element.__lastTime;if (lastTime === undefined) {lastTime = 0;}var currTime = Date.now();var timeToCall = Math.max(1, 33 - (currTime - lastTime));window.setTimeout(callback, timeToCall);element.__lastTime = currTime + timeToCall;};})();var readyStateCheckInterval = setInterval( function() {if (document.readyState === "complete") {clearInterval(readyStateCheckInterval);init();}
}, 10);//========================
//general properties for demo set up
//========================var canvas;
var context;
var canvasContainer;
var htmlBounds;
var bounds;
var minimumStageWidth = 250;
var minimumStageHeight = 250;
var maxStageWidth = 1000;
var maxStageHeight = 600;
var resizeTimeoutId = -1;
var stats;function init(){canvasContainer = document.getElementById("canvasContainer");window.onresize = resizeHandler;stats = new Stats();canvasContainer.appendChild( stats.getDisplayElement() );commitResize();
}function getWidth( element ){return Math.max(element.scrollWidth,element.offsetWidth,element.clientWidth );}
function getHeight( element ){return Math.max(element.scrollHeight,element.offsetHeight,element.clientHeight );}//avoid running resize scripts repeatedly if a browser window is being resized by dragging
function resizeHandler(){context.clearRect(0,0,canvas.width, canvas.height);clearTimeout(resizeTimeoutId);clearTimeoutsAndIntervals();resizeTimeoutId = setTimeout(commitResize, 300 );
}function commitResize(){if(canvas){canvasContainer.removeChild(canvas);}canvas = document.createElement('canvas');canvas.style.position = "absolute";context = canvas.getContext("2d");canvasContainer.appendChild(canvas);htmlBounds = new Sakri.Geom.Rectangle(0,0, getWidth(canvasContainer) , getHeight(canvasContainer));if(htmlBounds.width >= maxStageWidth){canvas.width = maxStageWidth;canvas.style.left = htmlBounds.getCenterX() - (maxStageWidth/2)+"px";}else{canvas.width = htmlBounds.width;canvas.style.left ="0px";}if(htmlBounds.height > maxStageHeight){canvas.height = maxStageHeight;canvas.style.top = htmlBounds.getCenterY() - (maxStageHeight/2)+"px";}else{canvas.height = htmlBounds.height;canvas.style.top ="0px";}bounds = new Sakri.Geom.Rectangle(0,0, canvas.width, canvas.height);context.clearRect(0,0,canvas.width, canvas.height);if(bounds.width<minimumStageWidth || bounds.height<minimumStageHeight){stageTooSmallHandler();return;}var textInputSpan = document.getElementById("textInputSpan");textInputSpan.style.top = htmlBounds.getCenterY() + (bounds.height/2) + 20 +"px";textInputSpan.style.left = (htmlBounds.getCenterX() - getWidth(textInputSpan)/2)+"px";startDemo();
}function stageTooSmallHandler(){var warning = "Sorry, bigger screen required :(";context.font = "bold normal 24px sans-serif";context.fillText(warning, bounds.getCenterX() - context.measureText(warning).width/2, bounds.getCenterY()-12);
}//========================
//Demo specific properties
//========================var animating = false;
var particles = [];
var numParticles = 4000;
var currentText = "SAKRI";
var fontRect;
var fontProperties = new Sakri.CanvasTextProperties(Sakri.CanvasTextProperties.BOLD, null, 100);
var animator;
var particleSource = new Sakri.Geom.Point();;
var particleSourceStart = new Sakri.Geom.Point();
var particleSourceTarget = new Sakri.Geom.Point();var redParticles = ["#fe7a51" , "#fdd039" , "#fd3141"];
var greenParticles = ["#dbffa6" , "#fcf8fd" , "#99de5e"];
var pinkParticles = ["#fef4f7" , "#f2a0c0" , "#fb3c78"];
var yellowParticles = ["#fdfbd5" , "#fff124" , "#f4990e"];
var blueParticles = ["#9ca2df" , "#222a6d" , "#333b8d"];var particleColorSets = [redParticles, greenParticles, pinkParticles, yellowParticles, blueParticles];
var particleColorIndex = 0;var renderParticleFunction;
var renderBounds;
var particleCountOptions = [2000, 4000, 6000, 8000, 10000, 15000, 20000 ];
var pixelParticleCountOptions = [10000, 40000, 60000, 80000, 100000, 150000 ];function clearTimeoutsAndIntervals(){animating = false;
}function startDemo(){fontRect = new Sakri.Geom.Rectangle(Math.floor(bounds.x + bounds.width*.2), 0, Math.floor(bounds.width - bounds.width*.4), bounds.height);fontProperties.fontSize = 100;fontProperties.fontSize = Sakri.CanvasTextUtil.getFontSizeForWidth(currentText, fontProperties, fontRect.width, canvas);fontRect.y = Math.floor(bounds.getCenterY() - fontProperties.fontSize/2);fontRect.height = fontProperties.fontSize;renderBounds = fontRect.clone();renderBounds.x -= Math.floor(canvas.width *.1);renderBounds.width += Math.floor(canvas.width *.2);renderBounds.y -= Math.floor(fontProperties.fontSize *.5);renderBounds.height += Math.floor(fontProperties.fontSize *.6);context.font = fontProperties.getFontString();createParticles();context.globalAlpha = globalAlpha;animating = true;loop();
}function loop(){if(!animating){return;}stats.tick();renderParticles();window.requestAnimationFrame(loop, canvas);
}function createParticles(){context.clearRect(0,0,canvas.width, canvas.height);context.fillText(currentText, fontRect.x, fontRect.y);var imageData = context.getImageData(fontRect.x, fontRect.y, fontRect.width, fontRect.height);var data = imageData.data;var length = data.length;var rowWidth = fontRect.width*4;var i, y, x;particles = [];for(i=0; i<length; i+=4){if(data[i+3]>0){y = Math.floor(i / rowWidth);x = fontRect.x + (i - y * rowWidth) / 4;particles.push(x);//xparticles.push(fontRect.y + y);//yparticles.push(x);//xOriginparticles.push(fontRect.y + y);//yOrigin}}//console.log(particles.length);context.clearRect(0,0,canvas.width, canvas.height);//pre calculate random numbers used for particle movementxDirections = [];yDirections = [];for(i=0; i<directionCount; i++){xDirections[i] = -7 + Math.random() * 14;yDirections[i] = Math.random()* - 5;}
}var xDirections, yDirections;
//fidget with these to manipulate effect
var globalAlpha = .11; //amount of trails or tracers
var xWind = 0; //all particles x is effected by this
var threshold = 60; //if a pixels red component is less than this, return particle to it's original position
var amountRed = 25; //amount of red added to a pixel occupied by a particle
var amountGreen = 12; //amount of green added to a pixel occupied by a particle
var amountBlue = 1; //amount of blue added to a pixel occupied by a particle
var directionCount = 100; //number of random pre-calculated x and y directionsfunction renderParticles(){//fill renderBounds area with a transparent black, and render a nearly black textcontext.fillStyle = "#000000";context.fillRect(renderBounds.x, renderBounds.y, renderBounds.width, renderBounds.height);context.fillStyle = "#010000";context.fillText(currentText, fontRect.x, fontRect.y);var randomRed = amountRed -5 + Math.random()*10;var randomGreen = amountGreen -2 + Math.random()*4;var imageData = context.getImageData(renderBounds.x, renderBounds.y, renderBounds.width, renderBounds.height);var data = imageData.data;var rowWidth = imageData.width * 4;var index, i, length = particles.length;var d = Math.floor(Math.random()*30);xWind += (-.5 + Math.random());//move randomly left or rightxWind = Math.min(xWind, 1.5);//clamp to a maximum windxWind = Math.max(xWind, -1.5);//clamp to a minimum windfor(i=0; i<length; i+=4, d++ ){particles[i] += (xDirections[d % directionCount] + xWind);particles[i+1] += yDirections[d % directionCount];index = Math.round(particles[i] - renderBounds.x) * 4 + Math.round(particles[i+1] - renderBounds.y) * rowWidth;data[index] += randomRed;data[index + 1] += randomGreen;data[index + 2] += amountBlue;//if pixels red component is below set threshold, return particle to orginif( data[index] < threshold){particles[i] = particles[i+2];particles[i+1] = particles[i+3];}}context.putImageData(imageData, renderBounds.x, renderBounds.y);
}var maxCharacters = 10;function changeText(){var textInput = document.getElementById("textInput");if(textInput.value && textInput.text!=""){if(textInput.value.length > maxCharacters){alert("Sorry, there is only room for "+maxCharacters+" characters. Try a shorter name.");return;}if(textInput.value.indexOf(" ")>-1){alert("Sorry, no support for spaces right now :(");return;}currentText = textInput.value;clearTimeoutsAndIntervals();animating = false;setTimeout(commitResize, 100);}
}function changeSettings(){clearTimeoutsAndIntervals();animating = false;setTimeout(commitResize, 100);
}function setParticleNumberOptions(values){var selector = document.getElementById("particlesSelect");if(selector.options.length>0 && parseInt(selector.options[0].value) == values[0] ){return;}while(selector.options.length){selector.remove(selector.options.length-1);}for(var i=0;i <values.length; i++){selector.options[i] = new Option(values[i], values[i], i==0, i==0);}
}

运行效果：