3D Silverlight 1.0: Simple Collada parser

A while ago I made a very simple Collada parser that was written in JavaScript and drew on a HTML 5 <canvas>.
Silverlight 1.0 also makes use of JavaScript so converting it seemed like a good excercise. You can see it here. Fortunately I didn’t have to change much. Only the way in which the lines are drawn and filled.
Compare the JavaScript/HTML 5 syntax (this.ctx is the drawing context):

this.ctx.beginPath();
this.ctx.moveTo( point1.x, point1.y + 500 );
this.ctx.lineTo( point2.x, point2.y + 500 );
this.ctx.lineTo( point3.x, point3.y + 500 );
this.ctx.closePath();
this.ctx.stroke();
if( this.enableZFlatShading || this.enableFlatShading ) this.ctx.fill();

To the way it’s done in Silverlight 1.0 (if there’s another way to do this, please tell me, because I haven’t found out yet):

this.drawLine = function( fillColor, strokeWidth, strokeColor, point1, point2, point3 )
{
	var xamlString = '<Path Stroke="' +strokeColor+ '" StrokeThickness="' +strokeWidth+ '" StrokeLineJoin="Miter" StrokeMiterLimit="0" '
	if( fillColor != null )
		xamlString += 'Fill="' +fillColor+ '" ';

	xamlString += 'Data="M' + point1.x +','+ ( point1.y + 500 ) +
		' L' + point2.x +','+ ( point2.y + 500 ) +
		' ' + point3.x +','+ ( point3.y + 500 ) +
		' z"/>';

	var line = this.control.content.CreateFromXaml( xamlString );
	this.rootElem.children.add( line );
};

A bit more elaborate and less structured as you can see.

The Silverlight Downloader Object

Another thing I changed is the asynchronous loading of the collada document. Instead of using a JavaScript XMLHTTP request I use Silverlight’s Downloader object:

var plugin = self.rootElement.getHost();
var downloader = plugin.createObject( "downloader" );

downloader.addEventListener( "completed", self.parseCollada );
downloader.addEventListener( "downloadfailed", self.showErrorMessage );

downloader.open( "GET", colladaFile );
downloader.send();

There’s still a little cross browser stuff to do in the handler for the completed event:

var responseXML;

if ( window.ActiveXObject )
{
	responseXML = new ActiveXObject( "Microsoft.XMLDOM" );
	responseXML.async = false;
	responseXML.loadXML( sender.responseText );
}
else
{
	var parser = new DOMParser();
	responseXML = parser.parseFromString( sender.responseText, "text/xml" );
}

Files

• The HTML file
• collada.js
• SilverlightCollada.js
• util.js