Gentoo: No image size information in Dolphin

Gentoo Linux
Dolphin 16.04.3
Dolphin 16.04.3

One thing that was not working with my Gentoo installation was the information for image dimensions (and image data in general) in Dolphin. The resolution is to rebuild Dolphin with the semantic-desktop use flag turned on.

echo "kde-apps/dolphin semantic-desktop" >> /etc/portage/package.use/dolphin
emerge --ask kde-apps/dolphin

I thing that this flag should be on by default when building a system with KDE desktop profile or at least mentioned somewhere in the Gentoo wiki.

Gentoo Linux: Ugly fonts in NetBeans and how to fix them

I recently installed Gentoo GNU/Linux + KDE 5 on my dev machine. One thing that was bugging me was the crappy font rendering in NetBeans.

To relolve the problem, locate your netbeans.conf file. Usually under /etc in your NetBeans installation folder, and append to netbeans_default_options the follwing:

-J-Dswing.aatext=true -J-Dawt.useSystemAAFontSettings=lcd --laf Metal

This will enable font smoothing in SWING and use default system settings for font smoothing. The last entry –laf Metal sets the preferred UI theme for the IDE, it should be Swing based theme such as Metal or Numbus.

Happy coding 🙂

Hyper-V: How to change screen resolution in CentOS / Red Hat Enterprice Linux virtual machine

I’m thinking of doing a switch to GNU/Linux as my desktop OS yet again! (My last GNU/Linux desktop experience lasted for 5 years, then back to Windows.) This time giving CentOS 7 a try.

Why CentOS? I particularly like that, it’s one of the few GNU/Linux distributions out there providing LTS, which means I will have a stable development machine for at least 2 – 3 more years.

Making a decision to migrate or stay with Windows among other things is testing various aspects of the distribution such as how things works out of the box, installing various development tools / applications required for my area of work, etc..

For testing, CentOS 7 was installed on Hyper-V virtual machine. What I didn’t liked after the installation was the screen resolution that the machine was set to (1152×864) with now way of chaining it either from KDE System Settings or Hyper-V virtual machine properties.

After a bit of digging I learned that there is a frame buffer driver for Hyper-V and that CentOS unlike other distributions I have worked with, provides a tool called grubby for managing grub.cfg. It’s way easy to work with grubby than editing “/etc/default/grub” for example and running update-grub.

To set the desired screen resolution under Hyper-V. Open a terminal, and su. Then execute:

grubby --update-kernel=ALL --args="video=hyperv_fb:1280x1024"

and reboot the system.

NOTE: Replace 1280×1024 with the desired screen resolution.

See grubby man page if you need further info on what the a bought line does.

Force KDM fonts DPI – openSUSE

If the fonts on your login screen are too big, usually due to attaching external monitor, edit /etc/sysconfig/displaymanager, and append -dpi # to DISPLAYMANAGER_KDM_LOCALARGS.

For example:

DISPLAYMANAGER_KDM_LOCALARGS="-dpi 75"

You should restart KDM (rcxdm restart) after doing so.