kagamar: Version 3.3.4.1 on Ubuntu 20.04 works after next steps:
1) Modify one line in the file "/home/user/GOG Games/ADOM Ancient Domains Of Mystery English/start.sh":
LD_LIBRARY_PATH=./lib64/ ./adom64
2) Create symlink to the system "libsndio" file:
sudo ln -s /usr/lib/x86_64-linux-gnu/libsndio.so.7.0 "/home/user/GOG Games/ADOM Ancient Domains Of Mystery English/game/lib64/libsndio.so.6.1"
3) Download packages "libnettle6_3.4-1_amd64.deb" and "libhogweed4_3.4-1_amd64.deb" from Ubuntu 18.04:
packages.ubuntu.com/bionic/amd64/libnettle6/download
packages.ubuntu.com/bionic/amd64/libhogweed4/download
and extract files libnettle.so.6, libnettle.so.6.4, libhogweed.so.4, libhogweed.so.4.4 to the game library path:
"/home/user/GOG Games/ADOM Ancient Domains Of Mystery English/game/lib64/"
First of all: Thank you for this workaround.
It needs some improvements for it towork, though:
If you replace
sudo ln -s /usr/lib/x86_64-linux-gnu/libsndio.so.7.0 "/home/user/GOG Games/ADOM Ancient Domains Of Mystery English/game/lib64/libsndio.so.6.1"
With:
sudo ln -s /usr/lib/x86_64-linux-gnu/libsndio.so.7.0 "/home/$USER/GOG Games/ADOM Ancient Domains Of Mystery English/game/lib64/libsndio.so.6.1"
You won't have to replace the user directory with your own directory, as the builtin $USER variable takes care of that for you.
Another thing that's important is to put a colon ':' between the paths you are referencing as LD_LIBRARY_PATH:
Like so:
LD_LIBRARY_PATH="./lib64/:./adom64" ./"adom64"
However, as DTerminist mentioned later (Thank you!) , the ./adom64/ is not necessary to include in the LD_LIBRARY_PATH
The last line of the run_game procedure will have to be changed from:
LD_LIBRARY_PATH="./lib64/ ./adom64" ./"adom64"
to
LD_LIBRARY_PATH="./lib64/" ./"adom64"
in order for the workaround to work.
I have tested this on my Ubuntu 20.04.2 LTS installation and I could start ADOM without installing the 18.04 libnettle and libhogweed libraries.
The ones included with 20.04 worked just fine.