best GUI library for vector drawing program

[chewie54]

Hello,

What would be the best cross-platform GUI library to use for a vector
based CAD program ( something like Visio on Windows )   WxWidgets,
Tk,   PyQt,  Java Swing,  Java SWT,????   I need the capibility to
draw and edit in a window that looks like a page of paper so WYSIWYG
is very important,  and I need to save the drawings in vector based
file formats like PS, EPS,  SVG, as well as image formats like jpg,
png, and gif.  Also, the images need to be high resolution so that
they can be pasted into various other programs in Windows OS,  and
Linux OS,  and the Mac OS.

Thanks in advance,
Dan