[Rd] italic font on cairo devices in R 3.4

[frederik at ofb.net]

On Fri, Jul 07, 2017 at 07:08:52PM +0200, Ilia Kats wrote:
> Interesting. I did not have the package installed, but I did at some point
> extract Helvetica from some MacOSX font files and R was using that just fine
> until 3.3. This is how the plot looks in 3.4 (still using Helvetica):
> https://ptpb.pw/HikX.pdf . After removing Helvetica, installing the
> ttf-mscorefonts-installer package, and running fc-cache --force  the plot
> looks like this: https://ptpb.pw/CM8A.pdf

The second plot looks worse, in other words, and the Microsoft fonts
didn't help.

Maybe the Cairo device should be giving better warning messages.

Anyway it sounds like you are describing a regression so maybe someone
can track down the commit that created this problem.

Thanks,

Frederick


> Also note that the standard pdf device works fine: https://ptpb.pw/3Ml1.pdf
> , it's just the cairo devices (both pdf and svg) that have the issue.
> Unfortunately I need to use cairo_pdf due to unicode characters in axis
> labels.
> 
> Cheers, Ilia
> 
> 
> -------- Original Message --------
> Subject: Re: [Rd] italic font on cairo devices in R 3.4
> Date: 2017-07-07 18:17:34 +0200
> From: frederik
> To: Ilia Kats
> CC: r-devel, r-help
> > Hi Ilia,
> > 
> > I'm running Arch Linux, R 3.4.0.
> > 
> > Here's my test.pdf from your minimal example: https://ptpb.pw/HxsA.pdf
> > 
> > It doesn't look pixelated to me...
> > 
> > Here's a post that I wrote when I solved my last font problem in R,
> > almost 2 years ago:
> > 
> > https://stackoverflow.com/a/40940331/5087283
> > 
> > I had to install some Microsoft font packages, which is sad, because
> > there are some perfectly good free fonts that R could be using
> > instead. It could be considered a bug that R requires Microsoft fonts,
> > at least by default. However, does this even fix your problem? I.e. if
> > you install the corresponding Debian Microsoft font packages, does the
> > text appear anti-aliased?
> > 
> > Frederick
> > 
> > On Fri, Jul 07, 2017 at 10:30:46AM +0200, Ilia Kats wrote:
> > > [cross-post from R-help]
> > > 
> > > Hi all,
> > > 
> > > I have the following problem: Since R 3.4.0, italic fonts rendered on Cairo
> > > devices appear pixelated. Here's a minimal example:
> > > cairo_pdf('test.pdf')
> > > plot(1:10, ylab=expression(italic(test)))
> > > dev.off()
> > > 
> > > The same problem occurs with bolditalic, but not bold. I am using Debian
> > > Stretch. Several friends tried the same on their machines, another Debian
> > > machine has the same problem. On MacOSX the output was not pixelated, but it
> > > wasn't italic either. Ubuntu 16.04.2 xenial works fine. My impression is
> > > that R somehow can't find the proper font to use and falls back to something
> > > weird. Ideas?
> > > 
> > > Note that I'm not subscribed to the list, so please CC me in replies.
> > > 
> > > Cheers, Ilia
> > > 
> > > ______________________________________________
> > > R-devel at r-project.org mailing list
> > > https://stat.ethz.ch/mailman/listinfo/r-devel
> > > 
> 
> -- 
> The first is to ensure your partner understands that nature has root
> privileges - nature doesn't have to make sense.
> -- Telsa Gwynne
>