XSLT stylesheets for MathML

Publishing XHTML+MathML Documents on the Web

At the current time few browsers have "native" support for MathML, and none have native support for the Content part of MathML. However Mozilla and Amaya have good support for Presentation MathML, and for other browsers there are a range of extensions that will render MathML (in particular, WebEQ and MathPlayer from Design Science and Techexplorer from IBM).

The main disadvantage of using a third party extension to render MathML within a web page is that it requires specific markup to specify the rendering extension (so <applet> for Java applets, <embed> for plugins and <object> for Microsoft Behavior extensions). The use of such markup ties the document to one particular platform, whereas the ideal of publishing information on the Web is that it should be accessible to all using a range of tools. We present here a proposed mechanism for using the XSLT transformation language to avoid these drawbacks and to allow XML files that conform to the XHTML and MathML Recommendations to be rendered on a range of browsers, with no browser specific markup in the document. The document just requires a single processing instruction linking to the stylesheet described here. The stylesheet transforms the supplied XML file, adding whatever markup is required to render MathML in the current browser, and pass the resulting document to the browser for rendering. Clearly this does require that the browser supports XSLT transformations, which does mean that a relatively new browser is required, however the current versions of (at least) Internet Explorer, Netscape and Mozilla all support XSLT, so while XSLT support is not universal it is, or soon will be, available on the majority of desktop browsers.

Linking to stylesheets

In order to use these stylesheets you need to add one line such as the following to your document, before the top level <html> element.

<?xml-stylesheet type="text/xsl" href="mathml.xsl"?>
<?xml-stylesheet type="text/xsl" href="http://www.w3.org/Math/XSL/mathml.xsl"?>

The stylesheet mathml.xsl will render documents containing any part of MathML, including Content Elements. If the document does not contain any Content MathML, then as an alternative one may link to a slightly simpler stylesheet:

<?xml-stylesheet type="text/xsl" href="pmathml.xsl"?>
<?xml-stylesheet type="text/xsl" href="http://www.w3.org/Math/XSL/pmathml.xsl"?>

This avoids loading the XSLT required to transform Content MathML to Presentation MathML that is needed to display Content MathML in some platforms. Most of the examples presented here will use this second stylesheet as this is sufficient to demonstrate the rendering capabilities of the various systems.

Examples

Specifying Preferences

Normally the stylesheet will transform the input document to use a suitable MathML renderer, depending on the browser in use and any browser extensions that it detects. It tries a list of possibilities and selects the first one which appears to be installed.

One may control this behaviour, adding one rendering possibility to the front of the list of renderers to be attempted. This is accomplised by adding an attribute from the MathML preferences namespace to the top level html element of the input document. For example:

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
    "http://www.w3.org/TR/html4/loose.dtd">
<html pref:renderer="css">


</html>

from the pmathml-css example file specifies that the "css" rendering is to be preferred (in preference to Techexplorer or MathPlayer that might otherwise have been chosen in Internet Explorer).

Still to do....

There are still improvements to be made to these stylesheets and the documentation...

In particular the JavaScript code is not very robust at present.

Support for more browsers is particularly important, including porting the JavaScript/CSS code from Internet Explorer to Netscape to give an alternative on no-MathML builds of Mozilla and Netscape.

Current Browser support

OS	Browser	XSLT	MathML Renderer
OS	Browser	XSLT	Native Presentation	MathPlayer Behaviour	Techexplorer Behaviour	Techexplorer Plugin	CSS/Java Script
Windows	IE x, x < 5.0	no	no	no	no	no	no
	IE 5.0	wd-xsl	no	no	no	yes	no
	IE 5.5	wd-xsl	no	yes	yes	yes	no
	IE 5.0/MSXML3	yes	no	no	no	yes	no
	IE 5.5/MSXML3	yes	no	yes	yes	yes	yes
	IE 6	yes	no	yes	yes	yes	yes
	Netscape x, x <= 6.0	no	no	no	no	no	no
	Netscape 6.1	yes	no	no	no	yes	no
	Netscape 7.0	yes	yes	no	no	no	no
	Mozilla 0.9.4	yes	no	no	no	no	no
	Mozilla 0.9.4/MathML	yes	yes	no	no	no	no
	Mozilla 0.9.5+	yes	yes	no	no	no	no
	Amaya	no	yes	no	no	no	no
	Opera	no	no	no	no	no	no
	Lynx	no	no	no	no	no	no
Macintosh	IE 5.0	wd-xsl	no	no	no	yes	no
	Netscape x, x <= 6.0	no	no	no	no	no	no
	Netscape 6.1	yes	no	no	no	yes	no
	Mozilla	yes	no	no	no	no	no
	Opera	no	no	no	no	no	no
	Lynx	no	no	no	no	no	no
Linux / Unix	Netscape x, x <= 6.0	no	no	no	no	no	no
	Netscape 6.1	yes	no	no	no	yes	no
	Netscape 7.0	yes	yes	no	no	no	no
	Mozilla 0.9.4	yes	no	no	no	no	no
	Mozilla 0.9.4/MathML	yes	yes	no	no	no	no
	Mozilla 0.9.5+	yes	yes	no	no	no	no
	Amaya	no	yes	no	no	no	no
	Opera	no	no	no	no	no	no
	Lynx	no	no	no	no	no	no

Files in the Distribution