From jorismeys at gmail.com  Tue Feb 15 14:44:03 2011
From: jorismeys at gmail.com (Joris Meys)
Date: Tue, 15 Feb 2011 14:44:03 +0100
Subject: [Rd] readPNG gives warnings and doesn't execute sample code
 from help files
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	<C425001D-55D4-4411-BAE2-8308E76E310B@r-project.org>
	<AANLkTi=dW4Ch7CgRhsXx-Fz4LrkbuDHdm9sgLaKY672-@mail.gmail.com>
	<loom.20110215T141928-342@post.gmane.org>
	<AANLkTi=vq+JZd3Nvtr5VDMrLveei60VUxXei_bvqH4hw@mail.gmail.com>
Message-ID: <AANLkTik=z=u-jyCtSd8Ko0jJDERp=+apGzjnh00Txzv2@mail.gmail.com>

Sorry, correction. X11() is not supposed to do that. So on Windows,
per-pixel alpha is no option apparently. Any chance this will be
implemented in the future?

Cheers
Joris

PS : also thx to Simon for his helpful answer earlier.

On Tue, Feb 15, 2011 at 2:40 PM, Joris Meys <jorismeys at gmail.com> wrote:
> Thx again for your answer. I've tried X11() - which is supposed to
> support alpha per pixel as well, but on Windows that's still no avail.
> So basically, on Windows I can forget about alpha?
>
> Cheers
> Jors
>
> On Tue, Feb 15, 2011 at 2:20 PM, Ben Bolker <bbolker at gmail.com> wrote:
>> Joris Meys <jorismeys <at> gmail.com> writes:
>>
>>>
>>> I believed the standard plotting device on R in 2.12.1 would support
>>> per-pixel alpha. It does support alpha, as
>>>
>>> ?plot(1:2,type="l")
>>> ?polygon(c(1,1,2,2),c(1,2,2,1),col=rgb(60,100,60,60,maxColorValue=255))
>>>
>>> plots correctly. Which device should I use then?
>>
>> See
>>
>> http://developer.r-project.org/Raster/raster-RFC.html
>>
>> (near the bottom of the page, where it explains that the
>> Windows device supports alpha but not per-pixel alpha ...)
>>
>> ?cheers
>> ? ?Ben Bolker
>>
>> ______________________________________________
>> R-devel at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-devel
>>
>
>
>
> --
> Joris Meys
> Statistical consultant
>
> Ghent University
> Faculty of Bioscience Engineering
> Department of Applied mathematics, biometrics and process control
>
> tel : +32 9 264 59 87
> Joris.Meys at Ugent.be
> -------------------------------
> Disclaimer : http://helpdesk.ugent.be/e-maildisclaimer.php
>



-- 
Joris Meys
Statistical consultant

Ghent University
Faculty of Bioscience Engineering
Department of Applied mathematics, biometrics and process control

tel : +32 9 264 59 87
Joris.Meys at Ugent.be
-------------------------------
Disclaimer : http://helpdesk.ugent.be/e-maildisclaimer.php



[Rd] readPNG gives warnings and doesn't execute sample code from help files
Joris Meys