Script hiệu ứng phá vỡ video.

Đoạn mã javascript kết hợp HTML5 tạo hiệu ứng phá vỡ tan nát Video Clip khi người dùng click chuột vào video trong lúc đang phát. Ngay sau đó các mãnh vỡ sẽ được liền lại.




<script type="text/javascript">
//<![CDATA[
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 createTiles1k(){
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};
createTiles1k();
}
//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.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;
}

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]}
}

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;
}

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>

<body onload="init()" style="margin:0px;">

<div style="display:none">
<video id="sourcevid" autoplay="true" loop="true">
<source src="http://craftymind.com/factory/html5video/BigBuckBunny_640x360.mp4" type="video/mp4"/>
<source src="http://craftymind.com/factory/html5video/BigBuckBunny_640x360.ogv" type="video/ogg"/>
</video>
<canvas id="sourcecopy" width="640" height="360"></canvas>
</div>

<div align="center">
<canvas id="output" width="1000" height="600" onmousedown="dropBomb(event, this)" ></canvas>
</div>
</body>
        DÁN CODE VÀO HTML/JA....THAY VIDEO KHÁC.    CHÚC THÀNH CÔNG.