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

[Joris Meys]

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