For various font type and linespacing selected to 1 we get various distance of two baselines in paragraph. Where is any information about linespacing in dependence on font?
In a nutshell, default “single line spacing” is dictated by font metrics. The type designer decides the appropriate minimum distance between lines for the typeface, that value is not under the control of LibO. Most fonts set that distance to be around the 120% of the point size, but there are fonts like the GNU FreeFonts that have larger spacing (I’ve seen fonts with line spacings up to 130% or even more).
If you want to see this in action, compare Gentium Plus with Gentium Plus Compact
http://software.sil.org/gentium/
The only difference between both fonts is the default line spacing.