Re: [9fans] psutils et al

[Theo Honohan <theoh@chiark.greenend.org.uk>]

rog@vitanuova.com wrote:
> > I'm not sure whether managing the display orientation should be part
> > of "page"'s job.  Judging from the presence of the "u" option, and by
> > analogy with the way I seem to use real photos and sheets of paper,
> > I'm inclined to think that it is.
>
> well, it's certainly to do with the presentation end of the process
> (given the postscript "%%Orientation: (Portrait|Landscape)" header)
> however, i'm somewhat surprised there's not some way of specifying a
> page transformation to ghostscript which would avoid the painful
> process of doing it via bit manipulation of the displayed image...

It is perhaps surprising that there isn't a general mechanism.  On the
other hand, it is a driver-specific issue, which is addressed
adequately for the X11 case, at least.  As long as the driver used by
page produces images rather than drawing directly in a window, the
question of whether it's page or the driver that does the bit
manipulation is moot.  (And, if we agree that page should provide the
facility of rotating any displayed image, then page might as well do
it.)

>
> from a brief glance at the documentation, a ghostscript driver can
> specify an arbitrary transformation between user coords and device
> coords, so i imagine it should be possible to tell the plan 9 driver to
> rotate the page if the page orientation said so.

Yes, at the very least.