canvas背景
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2022-03-18 22:36:52
加入绘制字母 ......
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>canvas字母喷射效果</title>
<style>
*{
margin:0;
padding:0;
}
body{
background:#000000;
overflow:hidden;
}
</style>
</head>
<body>
<canvas id=canvas></canvas>
<script>
//页面命名空间 命名空间就是对象 需要用到this
var Canvas={};
Canvas.anim={
//初始化
init:function(){
var canvas=document.getElementById("canvas");
this.ctx=canvas.getContext("2d");//画笔，创建2d空间，加this相当于全局变量
canvas.width=window.innerWidth;
canvas.height=window.innerHeight;
this.letters="ABCDEFGHIJKLMNOPQRSTUVWXYZ";
this.cw=canvas.width;
this.ch=canvas.height;
this.particles=[];
},
//执行动画
render:function(){
//粒子的属性
var particle={
//显示的位置random为随机数0-1
x:this.cw/2,
y:this.ch,
character:this.letters[Math.floor(Math.random()*this.letters.length)],
//速度值
xSpeed: (Math.random()*20)-10,
ySpeed: (Math.random()*20)-10
}
this.particles.push(particle);
this.drawParticles();
},
//绘制字母
drawParticles: function(){
this.fadeCanvas();
var particleCount=this.particles.length;
var c=this.ctx;
for(var i=0;i<particleCount;i++){
var particle=this.particles[i];
c.font="12px sans-serif";
c.fillStyle="#ffffff";
c.fillText(particle.character,particle.x,particle.y);
particle.x += particle.xSpeed;
particle.y += particle.ySpeed;
// 驶近Y轴
particle.y *= 0.97;
}
},
//清除画布
fadeCanvas: function(){
this.ctx.fillStyle = "rgba(0,0,0,0.5)";
this.ctx.fillRect(0,0,this.cw,this.ch);
}
};
Canvas.anim.init();
setInterval(function(){
Canvas.anim.render();
},13);
</script>
</body>
</html>
加入绘制字母
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>canvas字母喷射</title>
<style>
*{
padding: 0px;
margin: 0px;
}
#canvas{
background-color:#000;
}
</style>
<body>
<canvas id="canvas"></canvas>
</body>
<script>
// 页面命名空间
var Canvas = {}
Canvas.anim = {
// 初始化
init: function(){
var canvas = document.getElementById("canvas");
this.ctx = canvas.getContext("2d");
canvas.width = window.innerWidth;
canvas.height = window.innerHeight;
this.cw = canvas.width;
this.ch = canvas.height;
// 随机字母
this.letters = "QWERTYUIOPLKJHGFDSAZXCVBNM";
// 位置
this.particles = [];
},
// 执行动画
rander: function(){
// 显示的位置
var particle = {
x: this.cw/2,
y: this.ch,
// 随机字母
character: this.letters[Math.floor(Math.random()*this.letters.length)],
// 速度值
xSpeed: (Math.random()*20)-10,
ySpeed: (Math.random()*20)-10
}
this.particles.push(particle);
this.drawParticles();
},
// 绘制字母
drawParticles: function(){
this.fadeCanvas();
var c = this.ctx;
// 喷射字母
var particleCount = this.particles.length;
for(var i=0;i<particleCount;i++){
var particle = this.particles[i];
c.font = "12px";
c.fillStyle = "#ffffff";
c.fillText(particle.character,particle.x,particle.y);
particle.x += particle.xSpeed;
particle.y += particle.ySpeed;
// 驶近Y轴
particle.y *= 0.97;
}
// 绘制名字
var fontParticleCount = Font.particles.length;
for(var i=0;i<fontParticleCount;i++){
var particle = Font.particles[i];
c.font = "12px";
c.fillStyle = "#ff00cc";
c.fillText(particle.character,particle.x,particle.y);
}
},
// 清除画布
fadeCanvas: function(){
this.ctx.fillStyle = "rgba(0,0,0,0.5)";
this.ctx.fillRect(0,0,this.cw,this.ch);
}
};
Canvas.anim.init();
var Font = {
init: function(){
this.startX = window.innerWidth/2-150;
this.startY = window.innerHeight/2-200;
this.speed = 130; // 速度值
this.smallSpace = 10; // 字母间隔
// 字母位置
this.particles = [];
},
// 执行动画
rander: function(xPoint, yPoint){
// 显示的位置
var particle = {
x: xPoint,
y: yPoint,
// 随机字母
character: "0",
}
this.particles.push(particle);
},
// 画I
draw_i: function(callback){
var _this = this;
var width=40,height=100;
// 画-
var draw_1 = function(){
var i = 0;
var intVal = setInterval(function(){
i++;
_this.rander(_this.startX+_this.smallSpace*i,_this.startY);
if(_this.smallSpace*i >= width){
clearInterval(intVal);
draw_2();
}
},_this.speed);
}
// 画|
var draw_2 = function(){
var i = 0;
var intVal = setInterval(function(){
i++;
_this.rander(_this.startX+width/2+_this.smallSpace/2,_this.startY+_this.smallSpace*i);
if(_this.smallSpace*i >= height){
clearInterval(intVal);
draw_3();
}
},_this.speed);
}
// 画-
var draw_3 = function(){
var i = 0;
var intVal = setInterval(function(){
i++;
_this.rander(_this.startX+_this.smallSpace*i,_this.startY+height+_this.smallSpace);
if(_this.smallSpace*i >= width){
clearInterval(intVal);
callback();
}
},_this.speed);
}
draw_1();
},
// 画心形
draw_v: function(callback){
var _this = this;
var v_startX = _this.startX;
var v_startY = _this.startY;
var width=80,height=100;
// 凹度,高
var concave = 15;
// 斜边，宽高
var hypotenuseWidth = 20;
var hypotenuseHeight = 100;
var draw_1 = function(){
var i = 0;
_this.rander(v_startX,v_startY+concave);
var intVal = setInterval(function(){
i++;
// 每次偏移量
var y = concave/(width/2/_this.smallSpace)*i;
_this.rander(v_startX-_this.smallSpace*i,v_startY+concave-y);
if(_this.smallSpace*i >= width/2){
v_startX = v_startX-_this.smallSpace*i;
v_startY = v_startY+concave-y;
clearInterval(intVal);
draw_2();
}
},_this.speed);
}
var draw_2 = function(){
var i = 0;
var intVal = setInterval(function(){
i++;
// 每次偏移量
var y = hypotenuseHeight/_this.smallSpace*i;
_this.rander(v_startX-_this.smallSpace*i,v_startY+y);
if(_this.smallSpace*i >= hypotenuseWidth){
v_startX = v_startX-_this.smallSpace*i;
v_startY = v_startY+y;
clearInterval(intVal);
draw_3();
}
},_this.speed);
}
var draw_3 = function(){
var i = 0;
var intVal = setInterval(function(){
i++;
// 每次偏移量
var x = (width/2+hypotenuseWidth)/_this.smallSpace*i;
_this.rander(v_startX+x,v_startY+_this.smallSpace*i);
if(_this.smallSpace*i >= height){
v_startX = v_startX+x;
v_startY = v_startY+_this.smallSpace*i;
clearInterval(intVal);
draw_4();
}
},_this.speed);
}
var draw_4 = function(){
var i = 0;
var intVal = setInterval(function(){
i++;
// 每次偏移量
var x = (width/2+hypotenuseWidth)/_this.smallSpace*i;
_this.rander(v_startX+x,v_startY-_this.smallSpace*i);
if(_this.smallSpace*i >= height){
v_startX = v_startX+x;
v_startY = v_startY-_this.smallSpace*i;
clearInterval(intVal);
draw_5();
}
},_this.speed);
}
var draw_5 = function(){
var i = 0;
var intVal = setInterval(function(){
i++;
// 每次偏移量
var y = hypotenuseHeight/_this.smallSpace*i;
_this.rander(v_startX-_this.smallSpace*i,v_startY-y);
if(_this.smallSpace*i >= hypotenuseWidth){
v_startX = v_startX-_this.smallSpace*i;
v_startY = v_startY-y;
clearInterval(intVal);
draw_6();
}
},_this.speed);
}
var draw_6 = function(){
var i = 0;
var intVal = setInterval(function(){
i++;
// 每次偏移量
var y = concave/(width/2/_this.smallSpace)*i;
_this.rander(v_startX-_this.smallSpace*i,v_startY+y);
if(_this.smallSpace*i >= width/2){
clearInterval(intVal);
callback();
}
},_this.speed);
}
draw_1();
},
// 画U
draw_u: function(callback){
var _this = this;
var width=60,height=120;
// 画U_|
var draw_1 = function(){
var i = 0;
var intVal = setInterval(function(){
i++;
_this.rander(_this.startX,_this.startY+_this.smallSpace*i);
if(_this.smallSpace*(i+2) >= height){
clearInterval(intVal);
draw_2();
}
},_this.speed);
}
// 画U_-
var draw_2 = function(){
var function1 = function(){
var i = 0;
// 处理的高度
var cHeight = _this.smallSpace*2;
var intVal = setInterval(function(){
i++;
/*
* 每次偏移量
* _this.smallSpace*2留的高度
*/
var y = cHeight/(width/_this.smallSpace)*i;
var y_point = _this.startY+(height-cHeight)+y;
_this.rander(_this.startX+_this.smallSpace*i,y_point);
if(_this.smallSpace*i >= width/2){
clearInterval(intVal);
function2();
}
},_this.speed);
}
var function2 = function(){
var i = 0;
var intVal = setInterval(function(){
i++;
// 处理的高度
var cHeight = _this.smallSpace*2;
/*
* 每次偏移量
* _this.smallSpace*2留的高度
*/
var y = cHeight/(width/_this.smallSpace)*i;
var y_point = _this.startY+(height-_this.smallSpace)-y;
_this.rander(_this.startX+width/2+_this.smallSpace*i,y_point);
if(_this.smallSpace*i >= width/2){
clearInterval(intVal);
draw_3();
}
},_this.speed);
}
function1();
}
// 画U_|
var draw_3 = function(){
var i = 0;
// 处理的高度
var cHeight = _this.smallSpace*2;
var intVal = setInterval(function(){
i++;
var y_point = _this.startY+(height-cHeight)-_this.smallSpace*i;
_this.rander(_this.startX+width,y_point);
if(_this.smallSpace*(i+3) >= height){
clearInterval(intVal);
callback();
}
},_this.speed);
}
draw_1();
}
};
Font.init();
setInterval(function(){
Canvas.anim.rander();
},20);
//Font.draw_v();
Font.draw_i(function(){
Font.startX += 150;
Font.draw_v(function(){
Font.startX += 120;
Font.draw_u(function(){});
});
});
</script>
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