I am trying to work out why the code below no-longer works in Firefox or Chrome.
The files were last modified over ten years ago.
The static svg dispays, but the script does not run. To my considerable surprise, it does work as it should in Edge, as does a more complicated diagram with interactive elements.
There is probably some obscure setting I need to doctor in Firefox, but I don't know where to look. I don't know when I last tried one of these files, but I would be fairly sure they still worked a couple of years ago.
The code is probably full of daftnesses, as I have done very little javascript, and I probably should now be using requestanimationframe, but that is not the point - it has worked, and still does in Edge.
(Question edited to remove link to irrelevant SMIL version of the animation.)
This is the html file:
<html>
<head>
<title>
SVG slider-crank animated by script
</title>
</head>
<body onload="main()">
<script type="text/javascript">
<!--
var svgdoc = null;
var crank = null;
var crosshead = null;
var conrod = null;
var pi = Math.PI;
function main()
{
var timer = null;
var angle = 0;
var diagram = document.getElementById('svg');
if (diagram && diagram.contentDocument)
{
svgdoc = diagram.contentDocument;
}
else
{
try
{
svgdoc = diagram.getSVGDocument();
}
catch(exception)
{
alert("Unable to get SVG document");
}
}
crank = svgdoc.getElementById('ShowCrank');
crosshead = svgdoc.getElementById('ShowCrosshead');
conrod = svgdoc.getElementById('ShowConRod');
timer = setInterval(function(){(angle = rotation(angle))}, 25);
}
function rotation(angle)
{
var step = 3;
var theta = angle * pi / 180;
var alpha = Math.asin(Math.sin(theta) / 5);
var offset = 100 * (Math.cos(theta) -1) - 500 * (Math.cos(alpha) - 1);
crank.setAttributeNS(null, 'transform', ("rotate(" + angle + ", 800, 300)"));
crosshead.setAttributeNS(null, 'transform', ("translate(" + offset + ", 0)"));
conrod.setAttributeNS(null, 'transform', ("translate(" + offset + ", 0) rotate(" + (alpha * 180 / pi) + ", 400, 300)"));
angle = angle < 360 - step ? angle + step : 0;
return angle;
}
-->
</script>
<object id="svg" type="image/svg+xml" data="Slider_Crank.svg" width="1200" height="800">
<param name="src" value="Slider_Crank.svg">
</object>
</body>
</html>
This is the svg file:
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg version="1.1"
baseProfile="full"
xmlns="http://www.w3.org/2000/svg"
xmlns:xlink="http://www.w3.org/1999/xlink"
xmlns:ev="http://www.w3.org/2001/xml-events"
width="1200"
height="800">
<title> Slider-Crank </title>
<defs>
<rect
id="Slidebar"
stroke-width="1"
stroke="black"
fill="silver"
fill-opacity="1"
x="0"
y="-12"
width="300"
height="24"
/>
<g id="Crosshead" stroke-width="1" stroke="black" fill-opacity="1">
<rect
fill="gold"
x="-50"
y="-25"
width="100"
height="50"
/>
<circle cx="0" cy="0" r="15" fill="white"/>
</g>
<g id="Crank" stroke-width="1" stroke="black" fill-opacity="1">
<path fill="silver"
d="M 99.959 40.000
A 40 40 0 0 0 99.959, -40.000
A 450 450 0 0 1 9.950, -49.000
A 50 50 0 1 0 9.950, 49.000
A 450 450 0 0 1 99.959, 40.000
z"/>
<circle cx="100" cy="0" r="25" fill="white"/>
<circle cx="0" cy="0" r="30" fill="lightgrey"/>
</g>
<g id="ConRod" stroke-width="1" stroke="black" fill-opacity="0.7">
<path fill="silver"
d="M 12.387 21.715
A 30 30 0 0 1 27.551 17.776
L 453.475 22.035
A 30 30 0 0 1 473.243 29.733
A 40 40 0 0 1 473.243 -29.733
A 30 30 0 0 1 453.475 -22.035
L 27.551 -17.776
A 30 30 0 0 1 12.387 -21.715
A 25 25 0 0 1 12.387 21.715
z"/>
<circle cx="0" cy="0" r="25" fill="silver"/>
<circle cx="0" cy="0" r="15" fill="white"/>
<circle cx="500" cy="0" r="40" fill="silver"/>
<circle cx="500" cy="0" r="25" fill="white"/>
</g>
</defs>
<use id="ShowTopSlidebar" xlink:href="#Slidebar" x="150" y="263"/>
<use id="ShowBottomSlidebar" xlink:href="#Slidebar" x="150" y="337"/>
<use id="ShowCrosshead" xlink:href="#Crosshead" x="400" y="300"/>
<use id="ShowCrank" xlink:href="#Crank" x="800" y="300"/>
<use id="ShowConRod" xlink:href="#ConRod" x="400" y="300"/>
</svg>