Message-ID: <06B0F37F-413F-4883-B86D-63239022E880@r-project.org>
Date: 2005-12-05T23:14:54Z
From: Simon Urbanek
Subject: sizing of quartz and x11 windows
In-Reply-To: <6D9ABFF1-D530-4150-93BD-8C5F7B8ED45A@mac.com>
On Dec 5, 2005, at 5:36 PM, Parlamis Franklin wrote:
> i am more wondering why 3" in the function call turns into 2 6/32"
> displayed. is this a standard error for everyone, or is it just
> my monitor/card-combo that creates it?
The discrepancy comes from the fact that the DPI density is not
necessarily calibrated exactly to your monitor. I don't remember what
Quartz uses (it is initialized to 72dpi, but I see no code that
changes it later), but the DPI for X11 is usually set to an arbitrary
default of 75 or 100 (see xdpyinfo|grep resol) which may not match
your display (in fact my 23" Apple display has 99.5x98.3 DPI
according to OS X so Apple knows what they're doing). You can use the
-dpi argument to specify your real DPI in X11. As of Quartz, unless
there is a way to set ipr in R directly I don't think you can change
it. Given that most modern displays have at least 100dpi, I'd vote to
change the Quartz default to 100...
Cheers,
Simon