建我创建了一个下拉阴影的SVG图像,采用纯SVG工作正常(见a live demo):SVG彩色投影滤镜失败时使用JavaScript
<!DOCTYPE html>
<html>
<body>
<svg xmlns="http://www.w3.org/2000/svg" version="1.1">
<defs>
<filter id="drop">
<feComponenttransfer result="offOut" in="SourceAlpha">
<feFuncA type="linear" />
<feFuncR type="discrete" tablevalues="1" />
<feFuncG type="discrete" />
<feFuncB type="discrete" />
</feComponentTransfer>
<feOffset result="shadow" dx="67" dy="0" in="offOut" />
<feGaussianBlur stdDeviation="8" result="blurOut" in="shadow" />
<feBlend in="SourceGraphic" in2="blurOut" mode="normal" />
</filter>
</defs>
<g>
<g filter="url(#drop)">
<image x="10" y="100" width="440" height="60" xlink:href="/images/pulpit.jpg"
preserveAspectRatio="defer"></image>
</g>
</g>
</svg>
</body>
</html>
这里的图像与红色的创建阴影,符合市场预期,但比我尝试创建和修改通过JavaScript的SVG,使用下面的代码(见a live demo):
<!DOCTYPE html>
<html>
<body>
<svg xmlns="http://www.w3.org/2000/svg" version="1.1" id="sv">
<rect width="90" height="90" stroke="green" stroke-width="3" fill="rgba(255,25,8,1)"
/>
<g id="gr">
<image x="10" y="100" width="440" height="60" xlink:href="/images/pulpit.jpg"
preserveAspectRatio="defer"></image>
</g>
</svg>
</body>
<script>
var feoffset = document.createElementNS("http://www.w3.org/2000/svg", "feOffset");
var feGaussianBlur = document.createElementNS("http://www.w3.org/2000/svg", "feGaussianBlur");
var filter = document.createElementNS("http://www.w3.org/2000/svg", "filter");
var definition = document.createElementNS("http://www.w3.org/2000/svg", "defs");
filter.setAttribute("id", "fPicture5");
filter.setAttribute("filterUnits", "userSpaceOnUse");
feoffset.setAttribute("result", "shadow");
feoffset.setAttribute("in", "offOut");
feoffset.setAttribute("dx", "67");
feoffset.setAttribute("dy", "0");
feGaussianBlur.setAttribute("result", "blurOut");
feGaussianBlur.setAttribute("in", "shadow");
feGaussianBlur.setAttribute("stdDeviation", "8");
var feBlend = document.createElementNS("http://www.w3.org/2000/svg", "feBlend");
var feCTransfer = document.createElementNS("http://www.w3.org/2000/svg", "feComponentTransfer");
var feFuncR = document.createElementNS("http://www.w3.org/2000/svg", "feFuncR");
var feFuncG = document.createElementNS("http://www.w3.org/2000/svg", "feFuncG");
var feFuncB = document.createElementNS("http://www.w3.org/2000/svg", "feFuncB");
feCTransfer.setAttribute("in", "SourceAlpha");
feCTransfer.setAttribute("result", "offOut");
feBlend.setAttribute("in", "SourceGraphic");
feBlend.setAttribute("in2", "blurOut");
feBlend.setAttribute("mode", "normal");
feFuncR.setAttribute("type", "discrete");
feFuncG.setAttribute("type", "discrete");
feFuncB.setAttribute("type", "discrete");
feFuncR.setAttribute("tablevalues", "1");
feFuncG.setAttribute("tablevalues", "0");
feFuncB.setAttribute("tablevalues", "0");
feCTransfer.appendChild(feFuncR);
feCTransfer.appendChild(feFuncG);
feCTransfer.appendChild(feFuncB);
filter.appendChild(feCTransfer);
filter.appendChild(feoffset);
filter.appendChild(feGaussianBlur);
filter.appendChild(feBlend);
definition.appendChild(filter);
document.getElementById("sv").appendChild(definition);
document.getElementById("gr").setAttribute("filter", "url(#fPicture5)");
</script>
</html>
结果是成功创建了图像,但阴影是黑色的。
我无法找到一种方法使其成为预期的红色,任何想法?
不,阴影应该是红色的,而不是像第一个小提琴那样黑色 – 2013-02-14 11:12:13
它们在Firefox上都是黑色的。 – 2013-02-14 11:16:05
我想让第二个小提琴变成红色,奇怪的是,第一个小提琴的阴影在Chrome上是红色的,而在Firefox上是黑色的(测试过),而第二个小提琴在浏览器上都是黑色的 – 2013-02-14 11:25:12