Dear László Zsidi
First of all, thanks for a well structured 3D rendering engine. The last few days I have been playing around with your code, to explore the possibilities for using it to render 3D files for an open source 3D file sharing platform that I've started working on.
The idea is to promote creativity and build up a community around the rapidly growing home-3Dprinter crowd.
I have taken your engine and tried to render a slightly different kind of 3D geometry. A geometry that could resemble some kind of 3D part that one would want to print. As for now it's just a triangle with a hole in it, to keep the file somewhat simple. 
The 3D file can be found here:
openthingie.com/rendererror/models/ ...
Now when I render the file I get something that looks slightly off:
openthingie.com/rendererror/view.ph ...
openthingie.com/rendererror/view.ph ...
I have tried to figure out where your engine needs fixing in order to render the file correctly but I have hit a brick wall. The last few hours I have spend time merely trying to figure out what all your variables does. For now It's resulted in the list, appended in the bottom of this email.
Can you point me in the right direction to where I need to rewrite your engine in order to get it rendering correctly?
All the best!
  David
	var $rgbR;  //Background R color
	var $rgbG;  //Background G color
	var $rgbB;  //Background B color
	var $_000;
	var $_001;     //Rendered image width
	var $_002;     //Rendered image height
	var $_003;     //Image center, height
	var $_004;     //Image center, width
	var $_005;     //Initial rotation, X
	var $_006;     //Initial rotation, Y
	var $_007;     //Rotation factor (degrees per render)
	var $_008;
	var $_009;     //Vertice count
	var $_010;     //Face count
	var $_011;    //
	var $_012	= Array();  //Face RGB color
	var $_013	= Array();
	var $_014	= Array();
	var $_015	= Array();   // XYZ coordinate face array
	var $_016	= Array();   // XYZ coordinate vertice array
	var $_017	= Array();