HTML5 Canvas 破碎重组的视频特效的示例代码

2020-04-25 07:39:58易采站长站整理

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。

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;