From bbolker at gmail.com  Tue Feb 15 14:20:59 2011
From: bbolker at gmail.com (Ben Bolker)
Date: Tue, 15 Feb 2011 13:20:59 +0000
Subject: [Rd]
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References: <AANLkTinVuFBRCoHHjQ_fAF5BXFFQ+sQPm7-Yq79MtqOL@mail.gmail.com>
	<C425001D-55D4-4411-BAE2-8308E76E310B@r-project.org>
	<AANLkTi=dW4Ch7CgRhsXx-Fz4LrkbuDHdm9sgLaKY672-@mail.gmail.com>
Message-ID: <loom.20110215T141928-342@post.gmane.org>

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



[Rd] =?utf-8?q?readPNG_gives_warnings_and_doesn=27t_execute_sampl?= =?utf-8?q?e_code=09from_help_files?=
Ben Bolker