Greetings!
I'm a big fan of krita and am very impressed with how powerful it is as an open source painting and image manipulation tool. I come from a feature-film visual effects background, in compositing. I've used krita for small things here and there: paint cleanup for texture projections, small mattepaintings, etc. There are a lot of great things about Krita which make it a really good fit for matte painting workflows and overall usage in a VFX pipeline:
- OpenColorIO support allows utilizing the studio color pipeline
- First class OpenEXR support allows painting natively in 16 bit half float encoding
I spent a lot of time showing other artists how useful it was and convincing them to use it. Then with the release of Krita 4.0, the distributed appimage stopped working with Centos 7.

In VFX, most of the big studios use Centos Linux. Currently and probably for the next couple of years they will be based on Centos 7.x. Many software vendors who build VFX programs like Nuke and Maya are following the VFX Reference Platform.

Currently when you try to launch the latest Krita appimage on Centos 7.8, it fails to start because of the version of glibc and Qt that was used to compile the software:

Code: Select all

$ ./krita-4.4.1-x86_64.appimage
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.8' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libkritaui.so.20)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.21' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libkritaui.so.20)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.8' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libkritaimage.so.20)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.21' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libkritaglobal.so.20)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.20' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libkritaglobal.so.20)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.9' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libQt5Widgets.so.5)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.9' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libQt5Gui.so.5)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.9' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libQt5Core.so.5)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.8' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libQt5Core.so.5)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.21' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libQt5Core.so.5)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.8' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libkritalibbrush.so.20)
./krita-4.4.1-x86_64.appimage: /lib64/libz.so.1: version `ZLIB_1.2.9' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libpng16.so.16)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.20' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libexiv2.so.27)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.21' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libexiv2.so.27)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.9' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libQt5Multimedia.so.5)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.8' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libkritaflake.so.20)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.21' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libkritaflake.so.20)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.21' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libkritapsd.so.20)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.21' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libkritapigment.so.20)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.9' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libQt5PrintSupport.so.5)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.9' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libQt5Xml.so.5)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.9' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libQt5Network.so.5)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.9' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libQt5DBus.so.5)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.8' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libicui18n.so.55)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.8' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libicuuc.so.55)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.9' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libQt5Svg.so.5)
./krita-4.4.1-x86_64.appimage: /lib64/libstdc++.so.6: version `CXXABI_1.3.9' not found (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libQt5Concurrent.so.5)
./krita-4.4.1-x86_64.appimage: /lib64/libgpg-error.so.0: no version information available (required by /tmp/.mount_krita-d95Gyy/usr/bin/../lib/libgcrypt.so.20)


One solution which has been suggested is to use singularity as suggested here: viewtopic.php?f=139&t=161122 - This is tough in a VFX scenario however as it requires root access. It can be difficult to convince an IT support person to go through steps like this to install a piece of software.

A couple years ago I got frustrated by this and spent about a week compiling Krita and all dependencies from source on Centos 7. It was hard but I got it working. This was for Krita 4.2.5. It required distributing quite a few of the library dependencies with the software, like the Qt libraries for example.

My question is, is there any interest from the developers in modifying the distributed appimage for Centos 7 support? I would be willing to help if there is interest.

Thanks!

There _is_ interest: but it is dependent on contribtutions either in the form of doing the work or the form of money -- but preferably the former, because we've got enough money to pay all our developers, but not enough time to do everything we want to do

boudewijn wrote:There _is_ interest: but it is dependent on contribtutions

Thanks for the reply

I totally understand about there not being enough time for everything you want to do! Fortunately I do have some extra time at the moment, and I am interested in contributing by doing work.

Would you be able to briefly point me in the right direction about resources info or people I could bother to get started in the right direction learning about the krita appimage build and packaging system?

I see there is an IRC so if I don't hear back maybe I'll hang out there for a bit and see who I can bother.

The scripts for building the appimage are in packaging/linux in the krita git repo. Adapting those back to CentOS shouldn't be really hard.

It seems the latest AppImage for Kita 5.0.2 almost works on CentOS 7.9, except for GPU support. If Display>Canvas Graphics Acceleration is enabled, the brush performance is extremely laggy, and it prints the following in the terminal I ran Krita from:

Failed to fetch display info: "current platform doesn't support fetching display information"

I I disable GPU support (Canvas Graphics Acceleration) it seems to run reasonably smoothly again. The GPU on the machine I'm testing on is a GTX 1080 Ti, and OpenGL support works fine in other applications (e.g. Blender).

Any idea how to fix this?

(edit: I should add that I'm using LD_LIBRARY_PATH to point to gcc 6.3.1's lib64 folder to get it to run, which is a much newer version gcc than CentOS ships with. Otherwise it complains about a bunch of missing libstdc++ libraries. CentOS 7.9 ships with gcc 4.8.5 by default).

I did get this working eventually by adding both the path to my gcc6.3.1/lib64 and /usr/lib/nvidia to LD_LIBRARY_PATH, and then running the AppImage. In Krita i needed to disable "Use texture buffer" to prevent the brushes from lagging.

It's not a great solution, as you either need to compile gcc from source or get it from somewhere else, as CentOS only comes with gcc4.8.5, but I guess it's more of a CentOS problem than a Krita problem...as CentOS is living in the past.

Hey there, I saw your post about the issues with running the latest Krita appimage on Centos 7.x. I understand you're a big fan of Krita and have used it for various tasks in your VFX workflows. You're frustrated that the appimage is incompatible with Centos 7.x.
It's great to hear that you're willing to help with the development of Krita on Centos 7.x, and the developers are interested in modifying the distributed appimage for Centos 7 support.
If you're looking for alternative solutions, consider checking out tuxcare.com. They offer various services, including support for Centos 7 and other Linux distributions.