[Rd] Plotmath on Fedora 31 broken with with pango >= 1.44 - workarounds?

[Paul Murrell]

The R-symfam branch (r78176) is now working, for my basic tests, on ...

Ubuntu (pango < 1.44)
Ubuntu (no pango)
Fedora (pango > 1.44)
Windows

I need help to confirm that this builds on macOS and that the basic 
tests work ...

https://github.com/pmur002/R-symfam-testing

Brian has been helping with the build, but I am still looking for 
someone who can run the tests please.  Happy to be fed PDF files to 
scrutinize myself;  it's generating the PDF files on macOS that I need 
help with.

Paul

On 6/04/20 2:59 pm, Paul Murrell wrote:
> Hi
> 
> The R branch ...
> 
> https://svn.r-project.org/R/branches/R-symfam/
> 
> ... is now set up so that it works "out of the box" on Fedora by setting 
> the default to be 'symbolfamily=cairoSymbolFont(family, usePUA=FALSE)' 
> when grSoftVersion()["pango"] is greater than "1.44".
> 
> This means that on Fedora 31 (at least on the Docker container I am 
> testing on) "sans"->"NimubusSans" is used as the symbol font by default 
> and R converts Adobe Symbol Encoding code points to non-PUA UTF8 code 
> points.  This is not the prettiest result, but it is a lot better than 
> the page full of missing glyphs that we had.
> 
> The default on less "bleeding edge" systems, e.g., my Ubuntu 18.04, 
> remains 'symbolfamily="Symbol"'.
> 
> The default on other platforms is supposed to be the same as it was, but 
> I need help to confirm that.  I have set up a github repo ...
> 
> https://github.com/pmur002/R-symfam-testing
> 
> ... that describes how to test this on macOS and Windows if anyone has 
> time to do so.
> 
> I will start trying to set up a Windows test unless someone beats me to it.
> 
> Paul
> 
> On 30/03/20 3:24 pm, Paul Murrell wrote:
>> Hi
>>
>> I have created an R branch that contains a potential fix ...
>>
>> https://svn.r-project.org/R/branches/R-symfam/
>>
>> This allows, for example, ...
>>
>> cairo_pdf(symbolfamily="OpenSymbol")
>>
>> ... to specify that the OpenSymbol family should be used as the 
>> "symbol" font (e.g., for "plotmath") in R.
>>
>> This is just a separate branch for now because, while I have tested it 
>> under Unbuntu 18.04 and Fedora 31, I cannot even build R for Windows 
>> (right now) or Mac (ever) and I do not want to drop a bomb on R-devel 
>> at this stage of the release process for R 4.0.0.
>>
>> The attached file contains at least an outline of steps required to do 
>> a minimal test if anyone wants to try the fix on Linux.
>>
>> cc'ing Simon and Jeroen in case they are able to help with checking 
>> that this builds and works on Mac and/or Windows.
>>
>> NOTEs:
>> - 'symbolfamily' can only be specified when a graphics device is 
>> opened, and it is then fixed for that device.
>> - on Windows, for cairo-based devices, the "symbol" font is still 
>> hard-coded as "Standard Symbols L"
>>
>> Paul
>>
>> On 30/03/20 8:15 am, Paul Murrell wrote:
>>> Hi
>>>
>>> Thanks for your input on this Iñaki and Nicolas.
>>>
>>> I am starting testing an R fix for this problem today.
>>>
>>> As suggested, the plan is to allow the R user to specify a font 
>>> family other than "symbol" for plotmath output (or, more generally, 
>>> in R parlance, for 'font=5' or 'fontface=5') on a Cairo-based 
>>> graphics device.
>>>
>>> Paul
>>>
>>>
>>> On 27/03/20 11:30 pm, Iñaki Ucar wrote:
>>>> On Wed, 25 Mar 2020 at 12:25, Nicolas Mailhot
>>>> <nicolas.mailhot using laposte.net> wrote:
>>>>>
>>>>> <snip>
>>>>>
>>>>> R brought this all on itself by hardcoding a Windows-only “Symbol” 
>>>>> font
>>>>> family name in its default conf. Linux systems are UTF-8 by default 
>>>>> for
>>>>> ~20 years now, they don’t need the forcing of magic font families to
>>>>> handle symbols not present in the 8-bit legacy Windows encodings.
>>>>>
>>>>> The actual effect of this conf is not the selection of font files with
>>>>> special and unusual symbols. It is to priorize fonts that match the
>>>>> "Symbol" magic name. And those fonts are few and crumbling on Linux
>>>>> systems, because no one has needed to bother with them since Linux
>>>>> switched to UTF-8 last millenium.
>>>>>
>>>>> Just stop using “Symbol” in R and things will work a lot better.
>>>>> Alternatively, prepare to maintain the “Symbol” aliasing stack in
>>>>> fontconfig (and fight with wine for it), because *no* *one* *else*
>>>>> *cares* about this legacy Windows-specific stuff.
>>>>
>>>> So, in the light of Nicolas' input (thanks!), I think that font
>>>> selection should be fixed upstream in R. I'd be happy to put all this
>>>> together in R's bugzilla, but I don't have an account. Could someone
>>>> please invite me?
>>>>
>>>> Iñaki
>>>>
>>>> ______________________________________________
>>>> R-devel using 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 using stat.auckland.ac.nz
http://www.stat.auckland.ac.nz/~paul/