HTML Canvas 全屏 [英] HTML Canvas Full Screen
问题描述
我正在使用 HTML Canvas 使用以下应用程序:http://driz.co.uk/粒子/
I'm playing with the following application using the HTML Canvas: http://driz.co.uk/particles/
目前它设置为 640x480 像素，但我想让它全屏显示，因为它将显示在投影仪上.但是，据我所知，我不能将画布大小设置为 100% 作为变量，只有数字而不是 %.使用 CSS 只会拉伸它，而不是让它真正全屏.
At the moment it is set to 640x480 pixels, but I would like to make it full screen as it will be shown a projector. However as far as I can tell I cannot set the canvas size to be 100% as the variables only except numbers and not the %. Using CSS just stretches it rather than making it actual full screen.
有什么想法吗?
尝试使用 jQuery 查找高度和宽度，但它破坏了画布，为什么?
Tried finding the height and width using jQuery but it breaks the canvas any ideas why?
var $j = jQuery.noConflict();
var canvas;
var ctx;
var canvasDiv;
var outerDiv;
var canvasW = $j('body').width();
var canvasH = $j('body').height();
//var canvasW = 640;
//var canvasH = 480;
var numMovers = 550;
var movers = [];
var friction = .96;
var radCirc = Math.PI * 2;
var mouseX, mouseY, mouseVX, mouseVY, prevMouseX = 0, prevMouseY = 0;
var isMouseDown = true;
function init()
{
canvas = document.getElementById("mainCanvas");
if( canvas.getContext )
{
setup();
setInterval( run , 33 );
}
}
function setup()
{
outerDiv = document.getElementById("outer");
canvasDiv = document.getElementById("canvasContainer");
ctx = canvas.getContext("2d");
var i = numMovers;
while( i-- )
{
var m = new Mover();
m.x = canvasW * .5;
m.y = canvasH * .5;
m.vX = Math.cos(i) * Math.random() * 25;
m.vY = Math.sin(i) * Math.random() * 25;
m.size = 2;
movers[i] = m;
}
document.onmousedown = onDocMouseDown;
document.onmouseup = onDocMouseUp;
document.onmousemove = onDocMouseMove;
}
function run()
{
ctx.globalCompositeOperation = "source-over";
ctx.fillStyle = "rgba(8,8,12,.65)";
ctx.fillRect( 0 , 0 , canvasW , canvasH );
ctx.globalCompositeOperation = "lighter";
mouseVX = mouseX - prevMouseX;
mouseVY = mouseY - prevMouseY;
prevMouseX = mouseX;
prevMouseY = mouseY;
var toDist = canvasW / 1.15;
var stirDist = canvasW / 8;
var blowDist = canvasW / 2;
var Mrnd = Math.random;
var Mabs = Math.abs;
var Msqrt = Math.sqrt;
var Mcos = Math.cos;
var Msin = Math.sin;
var Matan2 = Math.atan2;
var Mmax = Math.max;
var Mmin = Math.min;
var i = numMovers;
while( i-- )
{
var m = movers[i];
var x = m.x;
var y = m.y;
var vX = m.vX;
var vY = m.vY;
var dX = x - mouseX;
var dY = y - mouseY;
var d = Msqrt( dX * dX + dY * dY );
var a = Matan2( dY , dX );
var cosA = Mcos( a );
var sinA = Msin( a );
if( isMouseDown )
{
if( d < blowDist )
{
var blowAcc = ( 1 - ( d / blowDist ) ) * 2;
vX += cosA * blowAcc + .5 - Mrnd();
vY += sinA * blowAcc + .5 - Mrnd();
}
}
if( d < toDist )
{
var toAcc = ( 1 - ( d / toDist ) ) * canvasW * .0014;
vX -= cosA * toAcc;
vY -= sinA * toAcc;
}
if( d < stirDist )
{
var mAcc = ( 1 - ( d / stirDist ) ) * canvasW * .00022;
vX += mouseVX * mAcc;
vY += mouseVY * mAcc;
}
vX *= friction;
vY *= friction;
var avgVX = Mabs( vX );
var avgVY = Mabs( vY );
var avgV = ( avgVX + avgVY ) * .5;
if( avgVX < .1 ) vX *= Mrnd() * 3;
if( avgVY < .1 ) vY *= Mrnd() * 3;
var sc = avgV * .45;
sc = Mmax( Mmin( sc , 3.5 ) , .4 );
var nextX = x + vX;
var nextY = y + vY;
if( nextX > canvasW )
{
nextX = canvasW;
vX *= -1;
}
else if( nextX < 0 )
{
nextX = 0;
vX *= -1;
}
if( nextY > canvasH )
{
nextY = canvasH;
vY *= -1;
}
else if( nextY < 0 )
{
nextY = 0;
vY *= -1;
}
m.vX = vX;
m.vY = vY;
m.x = nextX;
m.y = nextY;
ctx.fillStyle = m.color;
ctx.beginPath();
ctx.arc( nextX , nextY , sc , 0 , radCirc , true );
ctx.closePath();
ctx.fill();
}
//rect( ctx , mouseX - 3 , mouseY - 3 , 6 , 6 );
}
function onDocMouseMove( e )
{
var ev = e ? e : window.event;
mouseX = ev.clientX - outerDiv.offsetLeft - canvasDiv.offsetLeft;
mouseY = ev.clientY - outerDiv.offsetTop - canvasDiv.offsetTop;
}
function onDocMouseDown( e )
{
isMouseDown = true;
return false;
}
function onDocMouseUp( e )
{
isMouseDown = true;
return false;
}
// ==========================================================================================
function Mover()
{
this.color = "rgb(" + Math.floor( Math.random()*255 ) + "," + Math.floor( Math.random()*255 ) + "," + Math.floor( Math.random()*255 ) + ")";
this.y = 0;
this.x = 0;
this.vX = 0;
this.vY = 0;
this.size = 0;
}
// ==========================================================================================
function rect( context , x , y , w , h )
{
context.beginPath();
context.rect( x , y , w , h );
context.closePath();
context.fill();
}
// ==========================================================================================
推荐答案
javascript 有
The javascript has
var canvasW = 640;
var canvasH = 480;
在里面.尝试更改这些以及画布的 css.
in it. Try changing those as well as the css for the canvas.
或者更好的是，让 initialize 函数根据 css 确定画布的大小！
Or better yet, have the initialize function determine the size of the canvas from the css!
响应您的编辑，更改您的 init 函数:
in response to your edits, change your init function:
function init()
{
canvas = document.getElementById("mainCanvas");
canvas.width = document.body.clientWidth; //document.width is obsolete
canvas.height = document.body.clientHeight; //document.height is obsolete
canvasW = canvas.width;
canvasH = canvas.height;
if( canvas.getContext )
{
setup();
setInterval( run , 33 );
}
}
还要从包装器中删除所有 css，这只会把东西搞砸.不过，您必须编辑 js 才能完全摆脱它们...不过我可以全屏显示.
Also remove all the css from the wrappers, that just junks stuff up. You have to edit the js to get rid of them completely though... I was able to get it full screen though.
html, body {
overflow: hidden;
}
编辑:document.width 和 document.height 已过时.替换为 document.body.clientWidth 和 document.body.clientHeight
Edit: document.width and document.height are obsolete. Replace with document.body.clientWidth and document.body.clientHeight
这篇关于HTML Canvas 全屏的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
