So, there's not really any built-in vector graphics stuff as such, Decker is pretty bitmap based. But if you look at the doco for the canvas widget it's got built in functions for drawing a polygon, a line, etc. I'd think if you write code to use these to dynamically draw whatever shape you want scaled to whatever size is necessary you could essentially do some vector-type graphics this way. If you come up with a particularly clever or general-purpose way of doing it then you could even make it a contraption or module and release it for others to use! This would take some coding though