From: Hidetoshi NAGAI <nagai@...>
Date: 2004-09-15T22:22:02+09:00
Subject: Re: ruby/tk - getting started

Hi, 

From: Martin DeMello <martindemello@yahoo.com>
Subject: ruby/tk - getting started
Date: Wed, 15 Sep 2004 21:19:56 +0900
Message-ID: <5pW1d.419414$M95.315449@pd7tw1no>
> on it; the bit I'm stuck at is getting the x,y coordinates of the
> mouseclick to be the coordinates on the canvas, rather than on the
> canvas display viewport. 

Probably, TkCanvas#canvasx (or canvasy) method satisfies you.

From Tcl/Tk's 'canvas' manual, 
-----------------------------------------------------------
 pathName canvasx screenx ?gridspacing?
       Given  a window x-coordinate in the canvas screenx,
       this command returns the canvas  x-coordinate  that
       is  displayed  at that location.  If gridspacing is
       specified, then the canvas coordinate is rounded to
       the nearest multiple of gridspacing units.
-----------------------------------------------------------

So, on Ruby/Tk, "<canvas>.canvasx(screenx, [gridspacing])" 
will return the value which you want.
-- 
                                  Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)