[plt-scheme] 'grabbing' the canvas/pasteboard? to scroll with the mouse pointer

Hi,

I'm trying to implement a 'grab and scroll' method that lets the
canvas be moved by the mouse pointer.

I'm pretty happy with getting the location via   get-x  get-y and
dc-location-to-editor-location,
but I'm trying to find an alternative to the 'scroll-to' to actually
do the moving?

(The idea is that while the left mouse button is down, the mouse
position is static with respect to the pasteboard position, but moves
with respect to the canvas.)

Cheers,

Stephen

--
Stephen De Gabrielle
s.degabrielle at ucl.ac.uk
Telephone +44 (0)20 7679 5242 (x45242)
Mobile                  079 851 890 45
Project: Making Sense of Information (MaSI)
http://www.uclic.ucl.ac.uk/annb/MaSI.html

UCLIC: University College London Interaction Centre
http://www.uclic.ucl.ac.uk/

Remax House - 31/32 Alfred Place
London - WC1E 7DP