I initially tried to use the existing .clang-format file,
but it does not match the code style (at least with clang-format 11)
and the formatting is not consistent across files.
Therefore, I decided to rewrite the .clang-format with some personal
preferences.
Used command
find . -iname "*.hpp" -o -iname "*.cpp" | xargs clang-format -i -style=file