Javascript 画布拉伸,而不是裁剪和开始位置
我得到了一块画布,上面有一些掉落的五彩纸屑,我用这个jquery更改了画布在Croll上的高度:Javascript 画布拉伸,而不是裁剪和开始位置,javascript,jquery,css,html,canvas,Javascript,Jquery,Css,Html,Canvas,我得到了一块画布,上面有一些掉落的五彩纸屑,我用这个jquery更改了画布在Croll上的高度: $(window).on("scroll touchmove", function () { $('#world').toggleClass('tiny', $(document).scrollTop() > 0); }); 但是画布只是被拉伸而不是被裁剪,所以五彩纸屑看起来很奇怪。 那是我的五彩纸屑: (function() { var COLORS, Confetti, NU
$(window).on("scroll touchmove", function () {
$('#world').toggleClass('tiny', $(document).scrollTop() > 0);
});
但是画布只是被拉伸而不是被裁剪,所以五彩纸屑看起来很奇怪。
那是我的五彩纸屑:
(function() {
var COLORS, Confetti, NUM_CONFETTI, PI_2, canvas, confetti, context, drawCircle, i, range, resizeWindow, xpos;
NUM_CONFETTI = 350;
COLORS = [[85, 71, 106], [174, 61, 99], [219, 56, 83], [244, 92, 68], [248, 182, 70]];
PI_2 = 2 * Math.PI;
canvas = document.getElementById("world");
context = canvas.getContext("2d");
window.w = 0;
window.h = 0;
resizeWindow = function() {
window.w = canvas.width = window.innerWidth;
return window.h = canvas.height = window.innerHeight;
};
window.addEventListener('resize', resizeWindow, false);
window.onload = function() {
return setTimeout(resizeWindow, 0);
};
range = function(a, b) {
return (b - a) * Math.random() + a;
};
drawCircle = function(x, y, r, style) {
context.beginPath();
context.arc(x, y, r, 0, PI_2, false);
context.fillStyle = style;
return context.fill();
};
xpos = 0.5;
document.onmousemove = function(e) {
return xpos = e.pageX / w;
};
window.requestAnimationFrame = (function() {
return window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame || function(callback) {
return window.setTimeout(callback, 1000 / 60);
};
})();
Confetti = (function() {
function Confetti() {
this.style = COLORS[~~range(0, 5)];
this.rgb = "rgba(" + this.style[0] + "," + this.style[1] + "," + this.style[2];
this.r = ~~range(2, 6);
this.r2 = 2 * this.r;
this.replace();
}
Confetti.prototype.replace = function() {
this.opacity = 0;
this.dop = 0.03 * range(1, 4);
this.x = range(-this.r2, w - this.r2);
this.y = range(-20, h - this.r2);
this.xmax = w - this.r;
this.ymax = h - this.r;
this.vx = range(0, 2) + 8 * xpos - 5;
return this.vy = 0.7 * this.r + range(-1, 1);
};
Confetti.prototype.draw = function() {
var ref;
this.x += this.vx;
this.y += this.vy;
this.opacity += this.dop;
if (this.opacity > 1) {
this.opacity = 1;
this.dop *= -1;
}
if (this.opacity < 0 || this.y > this.ymax) {
this.replace();
}
if (!((0 < (ref = this.x) && ref < this.xmax))) {
this.x = (this.x + this.xmax) % this.xmax;
}
return drawCircle(~~this.x, ~~this.y, this.r, this.rgb + "," + this.opacity + ")");
};
return Confetti;
})();
confetti = (function() {
var j, ref, results;
results = [];
for (i = j = 1, ref = NUM_CONFETTI; 1 <= ref ? j <= ref : j >= ref; i = 1 <= ref ? ++j : --j) {
results.push(new Confetti);
}
return results;
})();
window.step = function() {
var c, j, len, results;
requestAnimationFrame(step);
context.clearRect(0, 0, w, h);
results = [];
for (j = 0, len = confetti.length; j < len; j++) {
c = confetti[j];
results.push(c.draw());
}
return results;
};
step();
}).call(this);
(函数(){
var颜色、五彩纸屑、NUM_五彩纸屑、PI_2、画布、五彩纸屑、上下文、绘图圈、i、范围、大小窗口、XPO;
五彩纸屑数量=350;
颜色=[[85,71,106],[174,61,99],[219,56,83],[244,92,68],[248,182,70];
PI_2=2*Math.PI;
canvas=document.getElementById(“世界”);
context=canvas.getContext(“2d”);
窗口w=0;
h=0;
resizeWindow=函数(){
window.w=canvas.width=window.innerWidth;
返回窗口.h=canvas.height=window.innerHeight;
};
addEventListener('resize',resizeWindow,false);
window.onload=函数(){
返回setTimeout(resizeWindow,0);
};
范围=功能(a,b){
return(b-a)*Math.random()+a;
};
drawCircle=功能(x、y、r、样式){
context.beginPath();
弧(x,y,r,0,PI_2,false);
context.fillStyle=样式;
返回context.fill();
};
xpos=0.5;
document.onmousemove=函数(e){
返回xpos=e.pageX/w;
};
window.requestAnimationFrame=(函数(){
返回window.requestAnimationFrame | | window.webkitRequestAnimationFrame | | window.mozRequestAnimationFrame | | | window.oRequestAnimationFrame | | window.msRequestAnimationFrame | | |函数(回调){
返回窗口。设置超时(回调,1000/60);
};
})();
五彩纸屑=(函数(){
功能五彩纸屑(){
this.style=颜色[~~范围(0,5)];
this.rgb=“rgba(“+this.style[0]+”、“+this.style[1]+”、“+this.style[2]”);
这个.r=~~范围(2,6);
this.r2=2*this.r;
这个。替换();
}
Confetti.prototype.replace=函数(){
这是不透明度=0;
这个.dop=0.03*范围(1,4);
该.x=范围(-this.r2,w-this.r2);
this.y=范围(-20,h-this.r2);
this.xmax=w-this.r;
this.ymax=h-this.r;
这个.vx=范围(0,2)+8*xpos-5;
返回this.vy=0.7*this.r+范围(-1,1);
};
Confetti.prototype.draw=函数(){
var-ref;
this.x+=this.vx;
this.y+=this.vy;
this.opacity+=this.dop;
如果(this.opacity>1){
这是不透明度=1;
这个参数为.dop*=-1;
}
if(this.opacity<0 | | this.y>this.ymax){
这个。替换();
}
如果(!((0<(ref=this.x)和&ref 对于(i=j=1,ref=NUM_CONFETTI;1问题是,当画布尝试检测窗口。调整大小事件时,动画不会更改窗口的大小。相反,它只是收缩画布的包装,这使得动画很奇怪。我想你要做的是将溢出:隐藏;
添加到画布的容器,以便在更改大小时,画布内部可以保留其大小(通过在画布上设置高度:\uuuupx;
规则)
希望这有助于:
您可能可以删除窗口的侦听器。调整大小
编辑-溢出:隐藏;
不起作用:
只需从画布中删除规则position:fixed;
和height:100%;
。在页面加载时,画布已调整到正确的大小并保持在正确的位置。固定位置的元素将显示在静态位置的元素上。删除这两种样式,一切都应该与JSFIDL中的一样e