Issues with RTL language display

[Dev-iL]

There are issues with the way Right-to-Left (RTL) scripts/texts are displayed in-game. This applies to localizations of two languages available in Factorio: Arabic and Hebrew.
Below is a list of issues, as of version 0.16.51, ordered by descending severity in terms of effect on UI/UX.
This topic was previously discussed at length in this thread (...and many links in this post lead there).

1. Line breaks reverse line order

   Most notably affects campaign descriptions and message boxes (the ones closable with TAB, e.g. when a new game starts) - the first things a player encounters.
   Example from demo.ini:
   
   
   ↑ What it should look like vs. What it actually looks like ↓
   
   
   Notice two issues: 1) The order of the rows is reversed. 2) Lines wrap at wrong positions.
   
   To clarify, in terms of the order of reading (indicated by the numbers below):

   Code: Select all

   LTR (e.g. English):
   01 02 03 04 05 06 07
   08 09 10 11 12 13 14
   15 16 17
   
   RTL (e.g. Hebrew), proper:
   07 06 05 04 03 02 01
   14 13 12 11 10 09 08
               17 16 15
   
   RTL, current:
   17 16 15 14 13 12 11
   10 09 08 07 06 05 04
               03 02 01

   The cause of this is the interaction of the line-wrapping algorithm and the BiDi algorithm, where lines are wrapped after a certain number of characters, but since in RTL the logical character order is the opposite of the visual order, wraps are added after X characters from the end of the string rather than from its beginning.
2. Reversed UI direction

   Previously mentioned here. Illustration of how this was done on WinXP:
   
   Notice the reverse order of buttons, green arrows, positioning of text in the title, menubar entries, scrollbar alignment, side of start button rounding, gravity of the taskbar item etc.
   
   Currently, the majority of the texts are left-justified instead of right-justified. See 2nd image in the previous point, as well as:
   
   
   
   This is how it should appear:

   Code: Select all

   |                               ‏‫| גישה:      פומבי‏‫‮
   |                        ‏‫‮‏‫| זמן תגובה: 68 מילישניות
   

   Another effect of this is that physical units (strings like "100 kW" etc.) are untranslateable, as explained here.
   Likely cause: the order of UI elements from left to right when some physical quantity is presented is `[value] [SI-prefix][SI-symbol]` but this doesn't work when reading RTL.
   Current workaround: SI units and prefixes are untranslated.
3. Logical-to-visual text reversal script not applied to mods

   Last official comment on this was in 2016. See explanations about logical vs visual here: 1,2. To judge for yourself how bad this is, take a look at this post.
   I put this last only because mods aren't something all players encounter right from the start.

Crowdin-related issues:

1. newline is used to denote line breaks

   This is related to the way multi-line strings are defined, with a printf-esque `\n` character where a split would appear. One big issue here is that the newline "code" must not be translated, so we have to switch languages (and writing directions) mid-string to reproduce it. One cannot even judge whether the result is correct when looking at it (and it usually isn't!). Example:
   
   
   
   Suggestion: Instead of "\n" use a single character that is never used in strings, like # or $ or ^, which doesn't change the writing direction. Alternatively, eliminate this character altogether and make use of the multiline support of Crowdin. (Though more universal, this solution might require changes to the way strings are stored in the game files.)

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These are the major things that come to mind. If I see anything else I'll update this post. I encourage other players who are interested in RTL to add their own issues either as replies, or send me a PM and I'll update the OP.

[RamiTech]

I encountered the same problem with new lines (in Arabic), And suggested the same thing to use multiple lines support....