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From: erik quanstrom <quanstro@quanstro.net>
To: 9fans@9fans.net
Subject: Re: [9fans] radar for plan 9, and two draw funnies.
Date: Sat, 12 Dec 2009 15:00:49 -0500	[thread overview]
Message-ID: <94e0e78e118b2061dfbc997c199f14f6@ladd.quanstro.net> (raw)
In-Reply-To: <<20091212144519.GA2904@zoidberg.hsd1.mi.comcast.net>>

> On Fri, Dec 11, 2009 at 08:51:21PM -0500, erik quanstrom wrote:
> > 1.  for some reason the hw.gif (interstates) are
> > in cyan not red.  drawing the radar first and the
> > hw second yields inverse radar colors.
> In what order are you layering the images? According to [1] they are layered
> left to right as on the toggle bar.
>
> [1]http://www.srh.noaa.gov/jetstream/doppler/ridge_download.htm

i think that's beside the point here.  the colors get inverted regardless
of the order of composition.  try compose -t topo.jpg radar.gif hw.gif.
(this is the same order as on the site).  in this case the radar image has
the wrong colors.

it looks like an α² problem, but i don't think it is.  if you use an r8g8b8
base image, the color effects still happen.  m8a8 yields black.  i didn't
know that was legal, yet:
; gif -9 radar.gif|dd -count 1 -bs 50>[2=]; echo
       m8a8           0           0         600   ;

it's especially odd to try these two:
	; compose -c m8 -t topo.jpg radar.gif hw.gif
	; compose -c m8 -t topo.jpg hw.gif radar.gif

- erik



       reply	other threads:[~2009-12-12 20:00 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <<20091212144519.GA2904@zoidberg.hsd1.mi.comcast.net>
2009-12-12 20:00 ` erik quanstrom [this message]
     [not found] <<dd6fe68a0912120745w38f491a5y65da039556f936ab@mail.gmail.com>
2009-12-12 16:09 ` erik quanstrom
2009-12-12 18:57   ` Russ Cox
     [not found] <<dd6fe68a0912120655q18c8e3f3pd056284626b0ae4f@mail.gmail.com>
2009-12-12 15:25 ` erik quanstrom
2009-12-12 15:45   ` Russ Cox
2009-12-12  1:51 erik quanstrom
2009-12-12 14:45 ` Jacob Todd
2009-12-12 14:55 ` Russ Cox

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