canvas制作倒计时炫丽效果
<!DOCTYPE html>
<head>
<title>canvas倒计时</title>
<style>
.canvas{
display: block;
border: 1px solid #000;
margin: 50px auto;
}
</style>
</head>
<body>
<canvas class="canvas" id="canvas"></canvas>
<script>
var digit = [
[
[0,0,1,1,1,0,0],
[0,1,1,0,1,1,0],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[0,1,1,0,1,1,0],
[0,0,1,1,1,0,0]
], //
[
[0,0,0,1,1,0,0],
[0,1,1,1,1,0,0],
[0,0,0,1,1,0,0],
[0,0,0,1,1,0,0],
[0,0,0,1,1,0,0],
[0,0,0,1,1,0,0],
[0,0,0,1,1,0,0],
[0,0,0,1,1,0,0],
[0,0,0,1,1,0,0],
[1,1,1,1,1,1,1]
], //
[
[0,1,1,1,1,1,0],
[1,1,0,0,0,1,1],
[0,0,0,0,0,1,1],
[0,0,0,0,1,1,0],
[0,0,0,1,1,0,0],
[0,0,1,1,0,0,0],
[0,1,1,0,0,0,0],
[1,1,0,0,0,0,0],
[1,1,0,0,0,1,1],
[1,1,1,1,1,1,1]
], //
[
[1,1,1,1,1,1,1],
[0,0,0,0,0,1,1],
[0,0,0,0,1,1,0],
[0,0,0,1,1,0,0],
[0,0,1,1,1,0,0],
[0,0,0,0,1,1,0],
[0,0,0,0,0,1,1],
[0,0,0,0,0,1,1],
[1,1,0,0,0,1,1],
[0,1,1,1,1,1,0]
], //
[
[0,0,0,0,1,1,0],
[0,0,0,1,1,1,0],
[0,0,1,1,1,1,0],
[0,1,1,0,1,1,0],
[1,1,0,0,1,1,0],
[1,1,1,1,1,1,1],
[0,0,0,0,1,1,0],
[0,0,0,0,1,1,0],
[1,1,0,0,1,1,0],
[0,0,0,1,1,1,1]
], //
[
[1,1,1,1,1,1,1],
[1,1,0,0,0,0,0],
[1,1,0,0,0,0,0],
[1,1,1,1,1,1,0],
[0,0,0,0,0,1,1],
[0,0,0,0,0,1,1],
[0,0,0,0,0,1,1],
[0,0,0,0,0,1,1],
[1,1,0,0,0,1,1],
[0,1,1,1,1,1,0]
], //
[
[0,0,0,0,1,1,1],
[0,0,1,1,0,0,0],
[0,1,1,0,0,0,0],
[1,1,0,0,0,0,0],
[1,1,0,1,1,1,0],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[0,1,1,1,1,1,0]
], //
[
[1,1,1,1,1,1,1],
[1,1,0,0,0,1,1],
[0,0,0,0,1,1,0],
[0,0,0,0,1,1,0],
[0,0,0,1,1,0,0],
[0,0,0,1,1,0,0],
[0,0,1,1,0,0,0],
[0,0,1,1,0,0,0],
[0,0,1,1,0,0,0],
[0,0,1,1,0,0,0]
], //
[
[0,1,1,1,1,1,0],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[0,1,1,1,1,1,0],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[0,1,1,1,1,1,0]
], //
[
[0,1,1,1,1,1,0],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[0,1,1,1,0,1,1],
[0,0,0,0,0,1,1],
[0,0,0,0,0,1,1],
[0,0,0,0,1,1,0],
[0,0,0,1,1,0,0],
[0,1,1,0,0,0,0]
], //
[
[0,0,0,0],
[0,0,0,0],
[0,1,1,0],
[0,1,1,0],
[0,0,0,0],
[0,0,0,0],
[0,1,1,0],
[0,1,1,0],
[0,0,0,0],
[0,0,0,0],
] //: ]; var WINDOW_HEIGHT = 468;
var WINDOW_WIDTH = 1024;
var RADIUS = 8;
var MARGIN_TOP = 60;
var MARGIN_LEFT = 30; //const endTime = new Date(2017,1,03,28,18,09);
var endTime = new Date();
endTime.setTime(endTime.getTime()+3600*1000);
var curShowTimeSeconds = 0; var balls = [];
var colors = ['#33B5E5','#0099CC','#AA66CC','#9933CC','#99CC00','#669900','#FF8800','FF8888','#CC0000']; window.onload = function(){
var canvas = document.getElementById('canvas');
var cxt = canvas.getContext('2d'); canvas.height = WINDOW_HEIGHT;
canvas.width = WINDOW_WIDTH; curShowTimeSeconds = getCurrentShowTimeSeconds(); setInterval(function(){
render(cxt);
update();
},50);
}
function getCurrentShowTimeSeconds(){
var curTime = new Date();
var ret = endTime.getTime() - curTime.getTime();
ret = Math.round(ret/1000); return ret >=0? ret : 0;
}
function update(){ var nextShowTimeSeconds = getCurrentShowTimeSeconds(); var nextHours = parseInt(nextShowTimeSeconds / 3600);
var nextMinutes = parseInt((nextShowTimeSeconds -nextHours*3600)/ 60);
var nextSeconds = nextShowTimeSeconds % 60; var curHours = parseInt(curShowTimeSeconds / 3600);
var curMinutes = parseInt((curShowTimeSeconds -curHours*3600)/ 60);
var curSeconds = curShowTimeSeconds% 60; if(nextSeconds != curSeconds){ if(parseInt(curHours/10) != parseInt(nextHours/10)){
addBalls(MARGIN_LEFT + 0, MARGIN_TOP, parseInt(curHours/10));
}
if(parseInt(curHours%10) != parseInt(nextHours%10)){
addBalls(MARGIN_LEFT + 15*(RADIUS+1), MARGIN_TOP, parseInt(curHours/10));
}
if(parseInt(curMinutes/10) != parseInt(nextMinutes/10)){
addBalls(MARGIN_LEFT + 39*(RADIUS+1), MARGIN_TOP, parseInt(curMinutes/10));
}
if(parseInt(curMinutes%10) != parseInt(nextMinutes%10)){
addBalls(MARGIN_LEFT + 54*(RADIUS+1), MARGIN_TOP, parseInt(curMinutes%10));
}
if(parseInt(curSeconds/10) != parseInt(nextSeconds/10)){
addBalls(MARGIN_LEFT + 78*(RADIUS+1), MARGIN_TOP, parseInt(curSeconds/10));
}
if(parseInt(curSeconds%10) != parseInt(nextSeconds%10)){
addBalls(MARGIN_LEFT + 93*(RADIUS+1), MARGIN_TOP, parseInt(curSeconds%10));
} curShowTimeSeconds = nextShowTimeSeconds;
} updateBalls();
}
function updateBalls(){
for(var i= 0; i< balls.length; i++){
balls[i].x += balls[i].vx;
balls[i].y += balls[i].vy;
balls[i].vy += balls[i].g; if(balls[i].y >= canvas.height -RADIUS){ balls[i].y = canvas.height - RADIUS;
balls[i].vy = -balls[i].vy*0.65; //加一个摩擦力系数
}
} var cnt = 0;
for(var i= 0; i< balls.length; i++){
if(balls[i].x + RADIUS > 0 && balls[i].x - RADIUS < WINDOW_WIDTH){
balls[cnt++] = balls[i];
}
}
while(balls.length > Math.min(300,cnt)){
balls.pop();
}
}
function addBalls(x, y, num){
for(var i=0; i<digit[num].length; i++){
for(var j=0; j<digit[num][i].length; j++){
if(digit[num][i][j] == 1){
var aBall = {
x: x+j*2*(RADIUS+1) +(RADIUS+1),
y: y+i*2*(RADIUS+1) +(RADIUS+1),
g: 1.5+Math.random(),
vx: Math.pow(-1, Math.ceil(Math.random()*1000))*4,
vy: -5,
color: colors[Math.floor(Math.random()*colors.length)]
}; balls.push(aBall);
}
} }
}
function render(cxt){ cxt.clearRect(0,0, WINDOW_WIDTH, WINDOW_HEIGHT); var hours = parseInt(curShowTimeSeconds / 3600);
var minutes = parseInt((curShowTimeSeconds -hours*3600)/ 60);
var seconds = curShowTimeSeconds% 60; renderDigit(MARGIN_LEFT, MARGIN_TOP, parseInt(hours/10), cxt);
renderDigit(MARGIN_LEFT+15*(RADIUS+1), MARGIN_TOP, parseInt(hours%10), cxt);
renderDigit(MARGIN_LEFT+30*(RADIUS+1), MARGIN_TOP, 10, cxt);
renderDigit(MARGIN_LEFT+39*(RADIUS+1), MARGIN_TOP, parseInt(minutes/10), cxt);
renderDigit(MARGIN_LEFT+54*(RADIUS+1), MARGIN_TOP, parseInt(minutes%10), cxt);
renderDigit(MARGIN_LEFT+69*(RADIUS+1), MARGIN_TOP, 10, cxt);
renderDigit(MARGIN_LEFT+78*(RADIUS+1), MARGIN_TOP, parseInt(seconds/10), cxt);
renderDigit(MARGIN_LEFT+93*(RADIUS+1), MARGIN_TOP, parseInt(seconds%10), cxt); for(var i=0; i < balls.length; i++){
cxt.fillStyle = balls[i].color; cxt.beginPath();
cxt.arc(balls[i].x, balls[i].y, RADIUS, 0, 2*Math.PI, true);
cxt.closePath(); cxt.fill();
}
}
function renderDigit(x,y, num, cxt){ cxt.fillStyle = 'rgb(0,102,153)'; for(var i =0; i<digit[num].length; i++){
for(var j =0; j<digit[num][i].length; j++){
if(digit[num][i][j] == 1){
cxt.beginPath();
cxt.arc( x+j*2*(RADIUS+1)+(RADIUS+1), y+i*2*(RADIUS+1)+(RADIUS+1), RADIUS, 0, 2*Math.PI);
cxt.closePath();
cxt.fill();
}
}
}
}
</script> </body>
</html>
<!DOCTYPE html>
<head>
<title>canvas倒计时</title>
<style>
.canvas{
display: block;
border: 1px solid #000;
margin: 50px auto;
}
</style>
</head>
<body>
<canvas class="canvas" id="canvas"></canvas> <script>
var ball = {x: 512, y:100, r:20, g:2, vx: -1, vy: 0, color: '#005588'};
window.onload = function(){
var canvas = document.getElementById('canvas');
var cxt = canvas.getContext('2d'); canvas.width = 1024;
canvas.height = 468; setInterval(function(){
render(cxt);
update();
},50);
}
function update(){
ball.x += ball.vx;
ball.y += ball.vy;
ball.vy += ball.g;
}
function render(cxt){
cxt.clearRect(0,0,cxt.canvas.width,canvas.height); cxt.fillStyle = ball.color;
cxt.beginPath();
cxt.arc(ball.x, ball.y, ball.r, 0, 2*Math.PI);
cxt.closePath(); cxt.fill();
}
</script>
</body>
</html>
<!DOCTYPE html>
<head>
<title>canvas倒计时</title>
<style>
.canvas{
display: block;
border: 1px solid #000;
margin: 50px auto;
}
</style>
</head>
<body>
<canvas class="canvas" id="canvas"></canvas>
<script>
var digit = [
[
[0,0,1,1,1,0,0],
[0,1,1,0,1,1,0],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[0,1,1,0,1,1,0],
[0,0,1,1,1,0,0]
], //
[
[0,0,0,1,1,0,0],
[0,1,1,1,1,0,0],
[0,0,0,1,1,0,0],
[0,0,0,1,1,0,0],
[0,0,0,1,1,0,0],
[0,0,0,1,1,0,0],
[0,0,0,1,1,0,0],
[0,0,0,1,1,0,0],
[0,0,0,1,1,0,0],
[1,1,1,1,1,1,1]
], //
[
[0,1,1,1,1,1,0],
[1,1,0,0,0,1,1],
[0,0,0,0,0,1,1],
[0,0,0,0,1,1,0],
[0,0,0,1,1,0,0],
[0,0,1,1,0,0,0],
[0,1,1,0,0,0,0],
[1,1,0,0,0,0,0],
[1,1,0,0,0,1,1],
[1,1,1,1,1,1,1]
], //
[
[1,1,1,1,1,1,1],
[0,0,0,0,0,1,1],
[0,0,0,0,1,1,0],
[0,0,0,1,1,0,0],
[0,0,1,1,1,0,0],
[0,0,0,0,1,1,0],
[0,0,0,0,0,1,1],
[0,0,0,0,0,1,1],
[1,1,0,0,0,1,1],
[0,1,1,1,1,1,0]
], //
[
[0,0,0,0,1,1,0],
[0,0,0,1,1,1,0],
[0,0,1,1,1,1,0],
[0,1,1,0,1,1,0],
[1,1,0,0,1,1,0],
[1,1,1,1,1,1,1],
[0,0,0,0,1,1,0],
[0,0,0,0,1,1,0],
[1,1,0,0,1,1,0],
[0,0,0,1,1,1,1]
], //
[
[1,1,1,1,1,1,1],
[1,1,0,0,0,0,0],
[1,1,0,0,0,0,0],
[1,1,1,1,1,1,0],
[0,0,0,0,0,1,1],
[0,0,0,0,0,1,1],
[0,0,0,0,0,1,1],
[0,0,0,0,0,1,1],
[1,1,0,0,0,1,1],
[0,1,1,1,1,1,0]
], //
[
[0,0,0,0,1,1,1],
[0,0,1,1,0,0,0],
[0,1,1,0,0,0,0],
[1,1,0,0,0,0,0],
[1,1,0,1,1,1,0],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[0,1,1,1,1,1,0]
], //
[
[1,1,1,1,1,1,1],
[1,1,0,0,0,1,1],
[0,0,0,0,1,1,0],
[0,0,0,0,1,1,0],
[0,0,0,1,1,0,0],
[0,0,0,1,1,0,0],
[0,0,1,1,0,0,0],
[0,0,1,1,0,0,0],
[0,0,1,1,0,0,0],
[0,0,1,1,0,0,0]
], //
[
[0,1,1,1,1,1,0],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[0,1,1,1,1,1,0],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[0,1,1,1,1,1,0]
], //
[
[0,1,1,1,1,1,0],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[1,1,0,0,0,1,1],
[0,1,1,1,0,1,1],
[0,0,0,0,0,1,1],
[0,0,0,0,0,1,1],
[0,0,0,0,1,1,0],
[0,0,0,1,1,0,0],
[0,1,1,0,0,0,0]
], //
[
[0,0,0,0],
[0,0,0,0],
[0,1,1,0],
[0,1,1,0],
[0,0,0,0],
[0,0,0,0],
[0,1,1,0],
[0,1,1,0],
[0,0,0,0],
[0,0,0,0],
] //: ]; var WINDOW_HEIGHT = 468;
var WINDOW_WIDTH = 1024;
var RADIUS = 8;
var MARGIN_TOP = 60;
var MARGIN_LEFT = 30; const endTime = new Date(2017,1,03,28,18,09);
var curShowTimeSeconds = 0; window.onload = function(){
var canvas = document.getElementById('canvas');
var cxt = canvas.getContext('2d'); canvas.height = WINDOW_HEIGHT;
canvas.width = WINDOW_WIDTH; curShowTimeSeconds = getCurrentShowTimeSeconds(); setInterval(function(){
render(cxt);
update();
},50);
}
function getCurrentShowTimeSeconds(){
var curTime = new Date();
var ret = endTime.getTime() - curTime.getTime();
ret = Math.round(ret/1000); return ret >=0? ret : 0;
}
function update(){ var nextShowTimeSeconds = getCurrentShowTimeSeconds(); var nextHours = parseInt(nextShowTimeSeconds / 3600);
var nextMinutes = parseInt((nextShowTimeSeconds -nextHours*3600)/ 60);
var nextSeconds = nextShowTimeSeconds % 60; var curHours = parseInt(curShowTimeSeconds / 3600);
var curMinutes = parseInt((curShowTimeSeconds -curHours*3600)/ 60);
var curSeconds = curShowTimeSeconds% 60; if(nextSeconds != curSeconds){ curShowTimeSeconds = nextShowTimeSeconds;
}
}
function render(cxt){ cxt.clearRect(0,0, WINDOW_WIDTH, WINDOW_HEIGHT); var hours = parseInt(curShowTimeSeconds / 3600);
var minutes = parseInt((curShowTimeSeconds -hours*3600)/ 60);
var seconds = curShowTimeSeconds% 60; renderDigit(MARGIN_LEFT, MARGIN_TOP, parseInt(hours/10), cxt);
renderDigit(MARGIN_LEFT+15*(RADIUS+1), MARGIN_TOP, parseInt(hours%10), cxt);
renderDigit(MARGIN_LEFT+30*(RADIUS+1), MARGIN_TOP, 10, cxt);
renderDigit(MARGIN_LEFT+39*(RADIUS+1), MARGIN_TOP, parseInt(minutes/10), cxt);
renderDigit(MARGIN_LEFT+54*(RADIUS+1), MARGIN_TOP, parseInt(minutes%10), cxt);
renderDigit(MARGIN_LEFT+69*(RADIUS+1), MARGIN_TOP, 10, cxt);
renderDigit(MARGIN_LEFT+78*(RADIUS+1), MARGIN_TOP, parseInt(seconds/10), cxt);
renderDigit(MARGIN_LEFT+93*(RADIUS+1), MARGIN_TOP, parseInt(seconds%10), cxt);
}
function renderDigit(x,y, num, cxt){ cxt.fillStyle = 'rgb(0,102,153)'; for(var i =0; i<digit[num].length; i++){
for(var j =0; j<digit[num][i].length; j++){
if(digit[num][i][j] == 1){
cxt.beginPath();
cxt.arc( x+j*2*(RADIUS+1)+(RADIUS+1), y+i*2*(RADIUS+1)+(RADIUS+1), RADIUS, 0, 2*Math.PI);
cxt.closePath();
cxt.fill();
}
}
}
}
</script>
<script>
var ball = {x: 512, y:100, r:20, g:2, vx: -1, vy: 0, color: '#005588'};
window.onload = function(){
var canvas = document.getElementById('canvas');
var cxt = canvas.getContext('2d'); canvas.width = 1024;
canvas.height = 468; setInterval(function(){
render(cxt);
update();
},50);
}
function update(){
ball.x += ball.vx;
ball.y += ball.vy;
ball.vy += ball.g; if(ball.y >= canvas.height -ball.r){ ball.y = canvas.height - ball.r;
ball.vy = -ball.vy*0.6; //加一个摩擦力系数
}
}
function render(cxt){
cxt.clearRect(0,0,cxt.canvas.width,canvas.height); cxt.fillStyle = ball.color;
cxt.beginPath();
cxt.arc(ball.x, ball.y, ball.r, 0, 2*Math.PI);
cxt.closePath(); cxt.fill();
}
</script>
</body>
</html>
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