Bug#900364: paraview: Paraview viewer mishandles fractional Qt screen scaling

[Oliver Sander]

Package: paraview
Version: 5.4.1+dfsg4-3
Severity: normal

I use a KDE desktop with fractional screen scaling enabled,
more specifically, on my system

~> echo $QT_SCREEN_SCALE_FACTORS 
eDP-1=1.5;DP-1=1.5;HDMI-1=1.5;HDMI-2=1.5;

As a result, only parts of the Paraview rendering window are actually
used for rendering---the rest remains black.  I'll attach a screenshot.
The problem disappears when I set

export QT_SCREEN_SCALE_FACTORS=eDP-1=1

The problem also disappears when I switch the Paraview window to full-screen
mode.


-- System Information:
Debian Release: buster/sid
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.16.0-1-amd64 (SMP w/4 CPU cores)
Locale: LANG=de_DE.UTF-8, LC_CTYPE=de_DE.UTF-8 (charmap=UTF-8), LANGUAGE= (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages paraview depends on:
ii  libavcodec57       7:3.4.2-2+b1
ii  libavformat57      7:3.4.2-2+b1
ii  libavutil55        7:3.4.2-2+b1
ii  libc6              2.27-3
ii  libcgns3.3         3.3.0-6
ii  libexpat1          2.2.5-3
ii  libfreetype6       2.8.1-2
ii  libgcc1            1:8.1.0-3
ii  libgl1             1.0.0+git20180308-2
ii  libgl2ps1.4        1.4.0+dfsg1-2
ii  libglew2.0         2.0.0-5
ii  libhdf5-100        1.10.0-patch1+docs-4+b1
ii  libjpeg62-turbo    1:1.5.2-2+b1
ii  libjsoncpp1        1.7.4-3
ii  libnetcdf13        1:4.6.1-1
ii  libogg0            1.3.2-1+b1
ii  libopenmpi3        3.0.1.real-3
ii  libpng16-16        1.6.34-1
ii  libprotobuf10      3.0.0-9.1
ii  libpython2.7       2.7.15-1
ii  libqt5core5a       5.10.1+dfsg-6+b1
ii  libqt5gui5         5.10.1+dfsg-6+b1
ii  libqt5help5        5.10.1-2
ii  libqt5network5     5.10.1+dfsg-6+b1
ii  libqt5widgets5     5.10.1+dfsg-6+b1
ii  libqt5x11extras5   5.10.1-2
ii  libstdc++6         8.1.0-3
ii  libswscale4        7:3.4.2-2+b1
ii  libtheora0         1.1.1+dfsg.1-14+b1
ii  libtiff5           4.0.9-5
ii  libx11-6           2:1.6.5-1
ii  libxml2            2.9.4+dfsg1-6.1
ii  libxt6             1:1.1.5-1
ii  python-autobahn    17.10.1+dfsg1-2
ii  python-matplotlib  2.1.1-2
ii  python-mpi4py      2.0.0-3+b1
ii  python-six         1.11.0-2
ii  python-twisted     17.9.0-2
ii  tcl [tclsh]        8.6.0+9
ii  zlib1g             1:1.2.11.dfsg-1

Versions of packages paraview recommends:
ii  mpi-default-bin  1.13
ii  paraview-doc     5.4.1+dfsg4-3
pn  paraview-python  <none>

Versions of packages paraview suggests:
pn  h5utils     <none>
pn  hdf5-tools  <none>

-- no debconf information