R devel - Dec 2007 - [R] color palette from red to blue passing white (shifted from R-help)

Hi,
The move to sRGB is nice, is there any interest in adding an interface
to lcms, http://www.littlecms.com,
to allow gamut matching? I can think of a lot of instances where I would
like to render a
figure as it would appear on my printer. This is probably best done as a
separate package though,
at least at first.

Nicholas


Martin Maechler wrote:
>>>>>> "Paul" == Paul Murrell <p.murrell at
auckland.ac.nz>
>>>>>>     on Wed, 05 Dec 2007 08:53:10 +1300 writes:
> 
>     Paul> Hi
>     Paul> Achim and I have been looking at tidying up the colorspace
package (see
>     Paul> http://r-forge.r-project.org/projects/colorspace/) to fix a
few
>     Paul> inaccuracies, PLUS the possibility of declaring R's
internal color space
>     Paul> to be sRGB.
> 
>     Paul> I have started an RFC on the r-developer site
>     Paul> (http://developer.r-project.org/sRGB-RFC.html) to discuss some
possible
>     Paul> changes to the core engine and add-on packages.
> 
>     Paul> One of the issues will be consolidating some of the double-ups
(e.g.,
>     Paul> hcl() in base and the counterpart in package
'colorspace';  I did not
>     Paul> even know about convertColor()!).
> 
>     Paul> Ideally, we would have only one copy of the conversions
between the
>     Paul> various colorspaces (probably C code, then the various R-level
front
>     Paul> ends can all just run off the same internal code).
> 
>     Paul> A lot of these conversions exist now in 'colorspace',
but as Thomas
>     Paul> pointed out, the S4-ness of 'colorspace' is a problem
for making these
>     Paul> conversions part of base R.
> 
> Hmm, I think we are currently only required to keep 'base' not
> dependent on 'methods'.
> Why should 'grDevices' or new "standard R" package not be
> dependent on 'methods' ?
> Many of us would like to see S4 been used much more widely.

Great.  I will keep working on the RFC to see if I can propose a way to
reconcile all of the color-conversion and palette-selection code based
on a single sRGB representation in the R core and only one set of
conversion functions.

Paul

> Martin

Hi


Nicholas Lewin-Koh wrote:
> Hi,
> The move to sRGB is nice, is there any interest in adding an interface
> to lcms, http://www.littlecms.com,
> to allow gamut matching? I can think of a lot of instances where I would
> like to render a
> figure as it would appear on my printer. This is probably best done as a
> separate package though,
> at least at first.

I saw a mention of this when I began looking at Krita the other day
(because I had heard that it had good colour support).  Screen-to-print
would be a great thing to support.

Paul

> Nicholas
> 
> 
> Martin Maechler wrote:
>>>>>>> "Paul" == Paul Murrell <p.murrell at
auckland.ac.nz>
>>>>>>>     on Wed, 05 Dec 2007 08:53:10 +1300 writes:
>>     Paul> Hi
>>     Paul> Achim and I have been looking at tidying up the colorspace
package (see
>>     Paul> http://r-forge.r-project.org/projects/colorspace/) to fix
a few
>>     Paul> inaccuracies, PLUS the possibility of declaring R's
internal color space
>>     Paul> to be sRGB.
>>
>>     Paul> I have started an RFC on the r-developer site
>>     Paul> (http://developer.r-project.org/sRGB-RFC.html) to discuss
some possible
>>     Paul> changes to the core engine and add-on packages.
>>
>>     Paul> One of the issues will be consolidating some of the
double-ups (e.g.,
>>     Paul> hcl() in base and the counterpart in package
'colorspace';  I did not
>>     Paul> even know about convertColor()!).
>>
>>     Paul> Ideally, we would have only one copy of the conversions
between the
>>     Paul> various colorspaces (probably C code, then the various
R-level front
>>     Paul> ends can all just run off the same internal code).
>>
>>     Paul> A lot of these conversions exist now in
'colorspace', but as Thomas
>>     Paul> pointed out, the S4-ness of 'colorspace' is a
problem for making these
>>     Paul> conversions part of base R.
>>
>> Hmm, I think we are currently only required to keep 'base' not
>> dependent on 'methods'.
>> Why should 'grDevices' or new "standard R" package
not be
>> dependent on 'methods' ?
>> Many of us would like to see S4 been used much more widely.
> 
> 
> Great.  I will keep working on the RFC to see if I can propose a way to
> reconcile all of the color-conversion and palette-selection code based
> on a single sRGB representation in the R core and only one set of
> conversion functions.
> 
> Paul
> 
> 
>> Martin
> 
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
-- 
Dr Paul Murrell
Department of Statistics
The University of Auckland
Private Bag 92019
Auckland
New Zealand
64 9 3737599 x85392
paul at stat.auckland.ac.nz
http://www.stat.auckland.ac.nz/~paul/