RTL(Persian-Arabic)Letters Messed up in android studio editor

That's a Reported Bug in Android Studio.

https://code.google.com/p/android/issues/detail?id=57667

And according to the comment #19 and #21 this issue is about to solve in Android Studio 2.0 stable release (soon):

comment #19:

Release in Android Studio 2.0. set "editor.new.rendering=true" in in idea.properties as described in http://tools.android.com/tech-docs/configuration

Not turned on by default in IntelliJ 15, but user configurable.

comment #20:

I've added an example for how to configure it in http://tools.android.com/tech-docs/configuration

This is not going to be a user configurable option; we plan to enable it by default as soon as we've tested it and confirmed that its performance and stability is satisfactory.

For Android Studio 1.5 in Windows create file with name "idea.properties" in
C:\Users\ your_user_name_folder \ .AndroidStudio1.5
and write this in the file:

editor.new.rendering=true

I tested it and it works.

Salaam saeed
I find a way, it has already some errors, but better than nothing(kachi baazi hichi!!)
File > settings > Editor >colors&font> font
save a copy of the scheme , then uncheck the show monospace choice, then select Tahoma font. this work makes it better but not excellent.
my farsi is so better than English!!
خلاصه بهت بگم که فونت تاهوما رو انتخاب کن