canvas如何实现七巧板图案和粒子时钟效果？下面本篇文章就来给大家介绍一下。有一定的参考价值，有需要的朋友可以参考一下，希望对大家有所帮助。
canvas实现七巧板
<canvas id="canvas" width="800" height="800"></canvas>
<script>
var rangram = [
{ p: [{ x: 0, y: 0 }, { x: 800, y: 0 }, { x: 400, y: 400 }], color: "#caff67" },
{ p: [{ x: 0, y: 0 }, { x: 400, y: 400 }, { x: 0, y: 800 }], color: "#67becf" },
{ p: [{ x: 800, y: 0 }, { x: 800, y: 400 }, { x: 600, y: 600 }, { x: 600, y: 200 }], color: "#ef3d61" },
{ p: [{ x: 600, y: 200 }, { x: 600, y: 600 }, { x: 400, y: 400 }], color: "#f9f51a" },
{ p: [{ x: 400, y: 400 }, { x: 600, y: 600 }, { x: 400, y: 800 }, { x: 200, y: 600 }], color: "#a594c0" },
{ p: [{ x: 200, y: 600 }, { x: 400, y: 800 }, { x: 0, y: 800 }], color: "#fa8ecc" },
{ p: [{ x: 800, y: 400 }, { x: 800, y: 800 }, { x: 400, y: 800 }], color: "#f6ca29" },
]
var canvas = document.getElementById('canvas');
if (canvas.getContext) {
var context = canvas.getContext("2d");
for(var i = 0; i < rangram.length; i++){
draw(rangram[i],context);
}
}
function draw(seat,context){
context.beginPath();
var pointArr = seat.p;
context.moveTo(pointArr[0].x, pointArr[0].y);
for(var i = 1; i < pointArr.length; i++){
context.lineTo(pointArr[i].x, pointArr[i].y);
}
context.closePath();
context.fillStyle=seat.color;
context.fill();
context.lineWidth=3;
context.stroke();
context.shadowColor='#ddd';
context.shadowBlur=30;
}
canvas实现粒子时钟
<canvas id="canvas"></canvas>
<script src="./digit.js"></script>
<script>
var SCREEN_WIDTH = document.body.clientWidth;
var SCREEN_HEIGHT = document.body.clientHeight;
var currentTime = null;
var MARGIN_LEFT = Math.round(SCREEN_WIDTH / 10);
var MARGIN_TOP = Math.round(SCREEN_HEIGHT / 10);
var RADIUS = Math.round(SCREEN_WIDTH * 4 / 5 / 108) - 1;
var timerArr = [];
var balls = [];
const colors = ["#33B5E5", "#0099CC", "#AA66CC", "#9933CC", "#99CC00", "#669900", "#FFBB33", "#FF8800", "#FF4444", "#CC0000"]
window.onload = function () {
var canvas = document.getElementById('canvas');
var context = canvas.getContext("2d");
canvas.width = SCREEN_WIDTH;
canvas.height = SCREEN_HEIGHT;
if (canvas.getContext) {
var context = canvas.getContext('2d');
setInterval(function () {
upData();
rander(context);
}, 50);
}
}
function upData() {
currentTime = new Date();
var curHours = currentTime.getHours();
var curMinutes = currentTime.getMinutes();
var curSeconds = currentTime.getSeconds();
var HoursOne = parseInt(curHours / 10);
var HoursTwo = parseInt(curHours % 10);
var MinutesOne = parseInt(curMinutes / 10);
var MinutesTwo = parseInt(curMinutes % 10);
var SecondsOne = parseInt(curSeconds / 10);
var SecondsTwo = parseInt(curSeconds % 10);
if (HoursOne != timerArr[0]) {
addBalls(MARGIN_LEFT + 0, MARGIN_TOP, HoursOne);
}
if (HoursTwo != timerArr[1]) {
addBalls(MARGIN_LEFT + 15 * (RADIUS + 1), MARGIN_TOP, HoursTwo);
}
if (MinutesOne != timerArr[2]) {
addBalls(MARGIN_LEFT + 39 * (RADIUS + 1), MARGIN_TOP, MinutesOne);
}
if (MinutesTwo != timerArr[3]) {
addBalls(MARGIN_LEFT + 54 * (RADIUS + 1), MARGIN_TOP, MinutesTwo);
}
if (SecondsOne != timerArr[4]) {
addBalls(MARGIN_LEFT + 78 * (RADIUS + 1), MARGIN_TOP, SecondsOne);
}
if (SecondsTwo != timerArr[5]) {
addBalls(MARGIN_LEFT + 93 * (RADIUS + 1), MARGIN_TOP, SecondsTwo);
}
timerArr = [HoursOne, HoursTwo, MinutesOne, MinutesTwo, SecondsOne, SecondsTwo];
updataBall();
}
function updataBall() {
for (var i = 0; i < balls.length; i++) {
balls[i].x = balls[i].x + balls[i].vx;
balls[i].vy = balls[i].vy + balls[i].g;
balls[i].y = balls[i].y + balls[i].vy;
if (balls[i].y + RADIUS > SCREEN_HEIGHT) {
balls[i].y = SCREEN_HEIGHT - RADIUS;
balls[i].vy = - balls[i].vy * 0.8;
}
}
var t = 0;
for (var i = 0; i < balls.length; i++) {
if (balls[i].x + RADIUS > 0 && balls[i].x - RADIUS < SCREEN_WIDTH) {
balls[t++] = balls[i];
}
}
while(balls.length > t){
balls.pop();
}
}
function addBalls(x, y, number) {
for (var i = 0; i < digit[number].length; i++)
for (var j = 0; j < digit[number][i].length; j++)
if (digit[number][i][j] == 1) {
var obj = {
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() * 100)) * 4,
vy: -5,
color: colors[Math.floor(Math.random() * colors.length)]
}
balls.push(obj);
}
}
function rander(context) {
context.clearRect(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT);
var hours = currentTime.getHours();
var minutes = currentTime.getMinutes();
var seconds = currentTime.getSeconds();
renderDigit(MARGIN_LEFT, MARGIN_TOP, parseInt(hours / 10), context)
renderDigit(MARGIN_LEFT + 15 * (RADIUS + 1), MARGIN_TOP, parseInt(hours % 10), context)
renderDigit(MARGIN_LEFT + 30 * (RADIUS + 1), MARGIN_TOP, 10, context)
renderDigit(MARGIN_LEFT + 39 * (RADIUS + 1), MARGIN_TOP, parseInt(minutes / 10), context);
renderDigit(MARGIN_LEFT + 54 * (RADIUS + 1), MARGIN_TOP, parseInt(minutes % 10), context);
renderDigit(MARGIN_LEFT + 69 * (RADIUS + 1), MARGIN_TOP, 10, context);
renderDigit(MARGIN_LEFT + 78 * (RADIUS + 1), MARGIN_TOP, parseInt(seconds / 10), context);
renderDigit(MARGIN_LEFT + 93 * (RADIUS + 1), MARGIN_TOP, parseInt(seconds % 10), context);
randerBall(context);
}
function randerBall(context) {
for (var i = 0; i < balls.length; i++) {
context.fillStyle = balls[i].color;
context.beginPath();
context.arc(balls[i].x, balls[i].y, RADIUS, 0, Math.PI * 2, 0);
context.closePath();
context.fill();
}
}
function renderDigit(x, y, number, context) {
context.fillStyle = 'rgb(0,102,153)';
for (var i = 0; i < digit[number].length; i++)
for (var j = 0; j < digit[number][i].length; j++)
if (digit[number][i][j] == 1) {
context.beginPath();
context.arc(x + j * 2 * (RADIUS + 1) + (RADIUS + 1), y + i * 2 * (RADIUS + 1) + (RADIUS + 1), RADIUS, 0, 2 * Math.PI)
context.closePath();
context.fill()
}
}
</script>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
[
[0,0,0,1,1,0,0],
[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]
],//1
......更多炫酷html5、javascript特效代码，尽在： javascript特效 栏目！！
