Today, we continue to share examples of the effects of JavaScript implementations, and this article describes the use of JavaScript for water ripple effects. The water wave effect takes the picture as the background, the click image anywhere will trigger. Sometimes, we can create a very interesting solution using normal Javascript .
Online Demo Source Download
Step 1. Html
As before, the first is the HTML code:
<! DOCTYPE html>Step 2. CssHere is the CSS code used:
Body{background: #eee; Margin:0;padding:0}.example{background: #FFF; width:600px;border:1px #000 solid;margin:20px AUTO;PADDING:15PX;-MOZ-BORDER-RADIUS:3PX;-WEBKIT-BORDER-RADIUS:3PX} #water { width:500px; height:400px; Display:block; margin:0px Auto; Cursor:pointer;} #switcher { text-align:center; Overflow:hidden; margin:15px;} #switcher img { width:160px; height:120px;}
Step 3. JsHere's the main JavaScript code:
function Drop (x, Y, damping, shading, refraction, CTX, ScreenWidth, screenheight) {this.x = x; This.y = y; this.shading = shading; This.refraction = refraction; This.buffersize = this.x * THIS.Y; this.damping = damping; This.background = ctx.getimagedata (0, 0, screenwidth, screenheight). data; This.imagedata = ctx.getimagedata (0, 0, screenwidth, screenheight); This.buffer1 = []; This.buffer2 = []; for (var i = 0; i < this.buffersize; i++) {this.buffer1.push (0); This.buffer2.push (0); } this.update = function () {for (var i = this.x + 1, x = 1; i < this.buffersize-this.x; i++, X + +) { if ((x < this.x)) {This.buffer2[i] = ((This.buffer1[i-1] + this.buffer1[i + 1] + this.buffer1[i-t His.x] + this.buffer1[i + this.x])/2)-this.buffer2[i]; This.buffer2[i] *= this.damping; } else x = 0; } var temp = This.buffer1; This.buffer1 = This.buffer2;This.buffer2 = temp; } This.draw = function (CTX) {var imagedataarray = This.imageData.data; for (var i = this.x + 1, index = (this.x + 1) * 4; I < this.buffersize-(1 + this.x); i++, index + = 4) {var Xoffset = ~ ~ (this.buffer1[i-1]-this.buffer1[i + 1]); var yoffset = ~ ~ (this.buffer1[i-this.x]-this.buffer1[i + this.x]); var shade = xoffset * this.shading; var texture = index + (xoffset * this.refraction + yoffset * this.refraction * this.x) * 4; Imagedataarray[index] = this.background[texture] + shade; Imagedataarray[index + 1] = this.background[texture + 1] + shade; Imagedataarray[index + 2] = + This.background[texture + 2] + shade; } ctx.putimagedata (this.imagedata, 0, 0); }}var fps = 0;var Watereff = {//variables timestep:20, Refractions:2, Shading:3, damping:0.99, screenwidth:500, screenheight:400, Pond:null, TexTureimg:null, Interval:null, Backgroundurl: ' data_images/underwater1.jpg ',//initialization init:funct Ion () {var canvas = document.getElementById (' water '); if (canvas.getcontext) {//fps countrt fps = 0; SetInterval (function () {document.getElementById (' fps '). InnerHTML = fps/2 + ' fps '; fps = 0; }, 2000); Canvas.onmousedown = function (e) {var mouse = Watereff.getmouseposition (e). Sub (new Vector2d (canvas.offsetl EFT, Canvas.offsettop)); WATEREFF.POND.BUFFER1[MOUSE.Y * watereff.pond.x + mouse.x] + = 200; } canvas.onmouseup = function (e) {canvas.onmousemove = null; } canvas.width = This.screenwidth; Canvas.height = This.screenheight; this.textureimg = new Image (256, 256); THIS.TEXTUREIMG.SRC = This.backgroundurl; Canvas.getcontext (' 2d '). DrawImage (this.textureimg, 0, 0); This.pond = new Drop (this.screenwidth, This.screenheight, this.damping, This.shading, This.refractions, Canvas.getcontext (' 2d '), THIS.S Creenwidth, This.screenheight); if (this.interval! = null) {clearinterval (this.interval); } This.interval = SetInterval (Watereff.run, this.timestep); }},//Change image func changepicture:function (URL) {this.backgroundurl = URL; This.init (); },//Get mouse position func getmouseposition:function (e) {if (!e) {var e = window.event; } if (E.pagex | | e.pagey) {return new vector2d (E.pagex, E.pagey); } else if (E.clientx | | e.clienty) {return new vector2d (E.clientx, E.clienty); }},//Loop drawing run:function () {VAr ctx = document.getElementById (' water '). GetContext (' 2d '); Watereff.pond.update (); Watereff.pond.draw (CTX); fps++; }}window.onload = function () {watereff.init ();}
As you can see, the VECTOR2D function is used here, and this function is provided in the vector2d.js. Another difficult way is to use pure mathematics to achieve, interested can experiment with their own.
Related articles that may be of interest to you
- Web front-end developers and designers must read the essence of the article recommended
- Carefully selected excellent jquery Ajax page plug-ins and tutorials
- 12 Amazing ideas for 404 error page Design
- Let the website Move! 12 Excellent jQuery animation plugins
- 8 Cutting-Edge HTML5 & CSS3 effects "with source download"
This article links: How to use HTML5 Canvas to create water ripple effect
Compilation Source: Dream Sky focus on front-end development technology sharing web design resources
This article comes from "Dream Sky (http://www.cnblogs.com/lhb25/)"
How to use HTML5 Canvas to create water ripple effects