[Rd] plotting text with very small negative rotation hangs (PR#9301)

[Paul Murrell]

Hi


bolker at zoo.ufl.edu wrote:
> This is an OpenPGP/MIME signed message (RFC 2440 and 3156)
> --------------enig308510A16A445880F353C5C9
> Content-Type: text/plain; charset=ISO-8859-1
> Content-Transfer-Encoding: quoted-printable
> 
> 
> to trigger the bug:
> 
> plot(0:1,0:1)
> text(0.5,0.5,"abc",srt=3D-1e-9)
> 
> this doesn't happen for positive, small srt,
> or for negative srt with magnitude greater
> than about 1e-8 (the example in plot.phylo
> in the ape package triggers it, with a
> srt value of -3e-15).
> 
> plot(0:1,0:1)
> for (i in 1:10) {
>   cat(i,"\n")
>   text(0.5,0.5,"hello",srt=3D(-10^-i))
> }
> 
>   I have traced this a fair ways into
> the C code -- I think it happens somewhere
> in clipText -- but I'm not sure.  Sorry not
> to be able to provide a fix at the moment.


I can confirm a (ridiculously) long pause on CentOS.  Tracing deeper
into C code, it appears to be a loop in XmbRotCreateTextItem() in
rotate.c, which misses an important case when setting up loop
parameters.  I have committed a fix to r-devel which solves the problem
for the example above.

Paul


>   This is on Ubuntu 6.06, not sure whether
> it affects other platforms or not ...
> 
>   Ben Bolker
> 
>> version
>                _
> platform       i686-pc-linux-gnu
> arch           i686
> os             linux-gnu
> system         i686, linux-gnu
> status
> major          2
> minor          4.0
> year           2006
> month          10
> day            03
> svn rev        39566
> language       R
> version.string R version 2.4.0 (2006-10-03)
> 
> 
> --------------enig308510A16A445880F353C5C9
> Content-Type: application/pgp-signature; name="signature.asc"
> Content-Description: OpenPGP digital signature
> Content-Disposition: attachment; filename="signature.asc"
> 
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG v1.4.2.2 (GNU/Linux)
> Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org
> 
> iD8DBQFFNV75c5UpGjwzenMRAhu9AKCVHQ3khVCj1skWyn8wCHl2w0nkbQCfdct5
> zehYhcbw2bazsjuTvX9eAIk=
> =CL1h
> -----END PGP SIGNATURE-----
> 
> --------------enig308510A16A445880F353C5C9--
> 
> ______________________________________________
> 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/