南强小屋 Design By 杰米

也许你见过HTML5图片破碎动画特效,实现的原理也挺简单的。但是你应该没有见过视频也可以破碎重组,这个HTML5动画就是利用Canvas的相关特性,实现了点击鼠标让视频破碎重组的效果。在视频区域点击鼠标,即可让该区域的视频破碎,让后经过一段时间后,破碎的区域又可以重组还原,视觉效果非常棒。

HTML5 Canvas 破碎重组的视频特效的示例代码

HTML代码
 

        <video id="sourcevid" autoplay="true" loop="true">
            <source src="BigBuckBunny_640x360.mp4" type="video/mp4"/>
            <source src="BigBuckBunny_640x360.ogv" type="video/ogg"/>
        </video>
        <canvas id="sourcecopy" width="640" height="360"></canvas>
</div>
<div>
<center>
    <div style="z-index:1;position:relative;text-align:center;font-size:16px;font-weight:bold;width:1000px;top:60px;">Click video to blow it up!</div>
    <canvas id="output" width="1000" height="600" onmousedown="dropBomb(event, this)" style="border: 0 none">        </canvas>
</center>
</div>

JavaScript代码

var video;
var copy;
var copycanvas;
var draw;

var TILE_WIDTH = 32;
var TILE_HEIGHT = 24;
var TILE_CENTER_WIDTH = 16;
var TILE_CENTER_HEIGHT = 12;
var SOURCERECT = {x:0, y:0, width:0, height:0};
var PAINTRECT = {x:0, y:0, width:1000, height:600};

function init(){
    video = document.getElementById('sourcevid');
    copycanvas = document.getElementById('sourcecopy');
    copy = copycanvas.getContext('2d');
    var outputcanvas = document.getElementById('output');
    draw = outputcanvas.getContext('2d');
    setInterval("processFrame()", 33);
}
function createTiles(){
    var offsetX = TILE_CENTER_WIDTH+(PAINTRECT.width-SOURCERECT.width)/2;
    var offsetY = TILE_CENTER_HEIGHT+(PAINTRECT.height-SOURCERECT.height)/2;
    var y=0;
    while(y < SOURCERECT.height){
        var x=0;
        while(x < SOURCERECT.width){
            var tile = new Tile();
            tile.videoX = x;
            tile.videoY = y;
            tile.originX = offsetX+x;
            tile.originY = offsetY+y;
            tile.currentX = tile.originX;
            tile.currentY = tile.originY;
            tiles.push(tile);
            x+=TILE_WIDTH;
        }
        y+=TILE_HEIGHT;
    }
}

var RAD = Math.PI/180;
var randomJump = false;
var tiles = [];
var debug = false;
function processFrame(){
    if(!isNaN(video.duration)){
        if(SOURCERECT.width == 0){
            SOURCERECT = {x:0,y:0,width:video.videoWidth,height:video.videoHeight};
            createTiles();
        }
        //this is to keep my sanity while developing
        if(randomJump){
            randomJump = false;
            video.currentTime = Math.random()*video.duration;
        }
        //loop
        if(video.currentTime == video.duration){
            video.currentTime = 0;
        }
    }
    var debugStr = "";
    //copy tiles
    copy.drawImage(video, 0, 0);
    draw.clearRect(PAINTRECT.x, PAINTRECT.y,PAINTRECT.width,PAINTRECT.height);

    for(var i=0; i<tiles.length; i++){
        var tile = tiles[i];
        if(tile.force > 0.0001){
            //expand
            tile.moveX *= tile.force;
            tile.moveY *= tile.force;
            tile.moveRotation *= tile.force;
            tile.currentX += tile.moveX;
            tile.currentY += tile.moveY;
            tile.rotation += tile.moveRotation;
            tile.rotation %= 360;
            tile.force *= 0.9;
            if(tile.currentX <= 0 || tile.currentX >= PAINTRECT.width){
                tile.moveX *= -1;
            }
            if(tile.currentY <= 0 || tile.currentY >= PAINTRECT.height){
                tile.moveY *= -1;
            }
        }else if(tile.rotation != 0 || tile.currentX != tile.originX || tile.currentY != tile.originY){
            //contract
            var diffx = (tile.originX-tile.currentX)*0.2;
            var diffy = (tile.originY-tile.currentY)*0.2;
            var diffRot = (0-tile.rotation)*0.2;

            if(Math.abs(diffx) < 0.5){
                tile.currentX = tile.originX;
            }else{
                tile.currentX += diffx;
            }
            if(Math.abs(diffy) < 0.5){
                tile.currentY = tile.originY;
            }else{
                tile.currentY += diffy;
            }
            if(Math.abs(diffRot) < 0.5){
                tile.rotation = 0;
            }else{
                tile.rotation += diffRot;
            }
        }else{
            tile.force = 0;
        }
        draw.save();
        draw.translate(tile.currentX, tile.currentY);
        draw.rotate(tile.rotation*RAD);
        draw.drawImage(copycanvas, tile.videoX, tile.videoY, TILE_WIDTH, TILE_HEIGHT, -TILE_CENTER_WIDTH, -TILE_CENTER_HEIGHT, TILE_WIDTH, TILE_HEIGHT);
        draw.restore();
    }
    if(debug){
        debug = false;
        document.getElementById('trace').innerHTML = debugStr;
    }
}

function explode(x, y){
    for(var i=0; i<tiles.length; i++){
        var tile = tiles[i];

        var xdiff = tile.currentX-x;
        var ydiff = tile.currentY-y;
        var dist = Math.sqrt(xdiff*xdiff + ydiff*ydiff);

        var randRange = 220+(Math.random()*30);
        var range = randRange-dist;
        var force = 3*(range/randRange);
        if(force > tile.force){
            tile.force = force;
            var radians = Math.atan2(ydiff, xdiff);
            tile.moveX = Math.cos(radians);
            tile.moveY = Math.sin(radians);
            tile.moveRotation = 0.5-Math.random();
        }
    }
    tiles.sort(zindexSort);
    processFrame();
}
function zindexSort(a, b){
    return (a.force-b.force);
}

function dropBomb(evt, obj){
    var posx = 0;
    var posy = 0;
    var e = evt || window.event;
    if (e.pageX || e.pageY){
        posx = e.pageX;
        posy = e.pageY;
    }else if (e.clientX || e.clientY) {
        posx = e.clientX + document.body.scrollLeft + document.documentElement.scrollLeft;
        posy = e.clientY + document.body.scrollTop + document.documentElement.scrollTop;
    }
    var canvasX = posx-obj.offsetLeft;
    var canvasY = posy-obj.offsetTop;
    explode(canvasX, canvasY);
}

function Tile(){
    this.originX = 0;
    this.originY = 0;
    this.currentX = 0;
    this.currentY = 0;
    this.rotation = 0;
    this.force = 0;
    this.z = 0;
    this.moveX= 0;
    this.moveY= 0;
    this.moveRotation = 0;

    this.videoX = 0;
    this.videoY = 0;
}

/*
    getPixel
    return pixel object {r,g,b,a}
*/
function getPixel(imageData, x, y){
    var data = imageData.data;
    var pos = (x + y * imageData.width) * 4;
    return {r:data[pos], g:data[pos+1], b:data[pos+2], a:data[pos+3]}
}
/*
    setPixel
    set pixel object {r,g,b,a}
*/
function setPixel(imageData, x, y, pixel){
    var data = imageData.data;
    var pos = (x + y * imageData.width) * 4;
    data[pos] = pixel.r;
    data[pos+1] = pixel.g;
    data[pos+2] = pixel.b;
    data[pos+3] = pixel.a;
}
/*
    copyPixel
    faster then using getPixel/setPixel combo
*/
function copyPixel(sImageData, sx, sy, dImageData, dx, dy){
    var spos = (sx + sy * sImageData.width) * 4;
    var dpos = (dx + dy * dImageData.width) * 4;
    dImageData.data[dpos] = sImageData.data[spos];     //R
    dImageData.data[dpos+1] = sImageData.data[spos+1]; //G
    dImageData.data[dpos+2] = sImageData.data[spos+2]; //B
    dImageData.data[dpos+3] = sImageData.data[spos+3]; //A
}
</script>

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持。

标签:
HTML5,Canvas,破碎重组

南强小屋 Design By 杰米
广告合作:本站广告合作请联系QQ:858582 申请时备注:广告合作(否则不回)
免责声明:本站文章均来自网站采集或用户投稿,网站不提供任何软件下载或自行开发的软件! 如有用户或公司发现本站内容信息存在侵权行为,请邮件告知! 858582#qq.com
南强小屋 Design By 杰米

评论“HTML5 Canvas 破碎重组的视频特效的示例代码”

暂无HTML5 Canvas 破碎重组的视频特效的示例代码的评论...

稳了!魔兽国服回归的3条重磅消息!官宣时间再确认!

昨天有一位朋友在大神群里分享,自己亚服账号被封号之后居然弹出了国服的封号信息对话框。

这里面让他访问的是一个国服的战网网址,com.cn和后面的zh都非常明白地表明这就是国服战网。

而他在复制这个网址并且进行登录之后,确实是网易的网址,也就是我们熟悉的停服之后国服发布的暴雪游戏产品运营到期开放退款的说明。这是一件比较奇怪的事情,因为以前都没有出现这样的情况,现在突然提示跳转到国服战网的网址,是不是说明了简体中文客户端已经开始进行更新了呢?