Update localization guide

1 files changed, 61 insertions, 30 deletions

diff --git a/doc/Localization_manual.txt b/doc/Localization_manual.txt
index f31d2c7f6..33fcc1c08 100644
--- a/doc/Localization_manual.txt
+++ b/doc/Localization_manual.txt
@@ -1,44 +1,75 @@
-From the begining you need to have GNUgettext and PoEdit.
-GNUgettext package contains a set of tools to extract strings from the source code and 
-to create the Catalog to translation.
-PoEdit provide good interface for the translators.
+# Localization and translation guide
+
+The purpose of this guide is to describe how to contribute to the Slic3rPE translations. We use GNUgettext for extracting string resources from the project and PoEdit for editing translations.
 
 Those are possible to download here: 
-	GNUgettext	- https://sourceforge.net/directory/os:windows/?q=gnu+gettext
-	PoEdit		- https://poedit.net/
+-    https://sourceforge.net/directory/os:windows/?q=gnu+gettext GNUgettext package contains a set of tools to extract strings from the source code and to create the translation Catalog.
+-    https://poedit.net PoEdit provides good interface for the translators.
+
+After GNUgettext is installed it is recommended to add the path to gettext/bin to PATH variable.
+
+Full manual for GNUgettext you can see here: http://www.gnu.org/software/gettext/manual/gettext.html
+
+
+### Scenario 1. How do I add a translation or fix the existing translation
+1. Get PO-file from corresponding folder here:
+https://github.com/prusa3d/Slic3r/tree/master/resources/localization
+2. Open this file in PoEdit as "Edit a translation"
+3. Apply your corrections to translation
+4. Push changed Slic3rPE.po and Slic3rPE.mo (will create automatically after saving of Slic3r.po in PoEdit) back to to the enter folder.
+
+### Scenario 2. How do I add a new language support
+1. Get file Slic3rPE.pot here :
+https://github.com/prusa3d/Slic3r/tree/master/resources/localization
+2. Open it in PoEdit for "Create new translation"
+3. Select Translation Language (for example French).
+4. As a result you will have fr.po - the file contaning translation to French.
+Notice. When the transtation is complete you need to:
+    - Rename the file to Slic3rPE.po
+    - Click "Save file" button. Slic3rPE.mo will be created immediatly
+    - Both Slic3rPE.po and Slic3rPE.mo have to be saved here:
+https://github.com/prusa3d/Slic3r/tree/master/resources/localization/fr
+( name of folder "fr" means "French" - the translation language). 
 
-When GNUgettext and poEdit are downloaded and installationed, next step is 
-to add path to gettext/bin directory to your PATH variable.
-You can use gettext from cmdline now.
+### Scenario 3. How do I add a new text resource when implementing a feature to Slic3rPE
+Each string resource in Slic3rPE available for translation needs to be explicitly marked using L() macro like this:
+```C++
+auto msg = L("This message to be localized")
+```
+To get translated text use one of needed macro/function (`_(s)`, `_CHB(s)` or `L_str(s)` ).
+If you add new file resourse, add it to list of files contaned macro `L()`
 
+### Scenario 4. How do I use GNUgettext to localize my own application taking Slic3rPE as an example
 
-In Slic3rPE we have one macro (L) used to markup strings to localizations.
+1.  For conviniance create list of files with this macro `L(s)`. We have 
+https://github.com/prusa3d/Slic3r/tree/master/resources/localization/list.txt.
 
-So, to create Catalog to translation there are next steps:
-	1.  create list of files with this macro (list.txt)
+2.  Create template file(*.POT) with GNUgettext command:
+    ```
+        xgettext --keyword=L --from-code=UTF-8 --debug -o Slic3rPE.pot -f list.txt
+    ```
 
-	2.  create template file(*.POT) with command:
-		xgettext --keyword=L --from-code=UTF-8 --debug -o Slic3rPE.pot -f list.txt
-	    Use flag --from-code=UTF-8 to specify that the source strings are in UTF-8 encoding
-	    Use flag --debug to correctly extract formated strings(used %d, %s etc.)
+    Use flag `--from-code=UTF-8` to specify that the source strings are in UTF-8 encoding
+    Use flag `--debug` to correctly extract formated strings(used %d, %s etc.)
 
-	3.1 if you start to create PO-file for your projest just open this POT-file in PoEdit.
-	    When you select translation language after first opening of POT-files, 
-	    PO-file will be created immediatly.
+3.  Create PO- and MO-files for your project as described above.
 
-	3.2 if you already have PO-file created before, you have to merge old PO-file with
-	    strings from creaded POT-file. You can do that with command: 
-		msgmerge -N -o new.po old.po new.pot
-	    Use option -N to not using fuzzy matching when an exact match is not found.
+4.  To merge old PO-file with strings from creaded new POT-file use command:
+    ```
+        msgmerge -N -o new.po old.po new.pot
+    ```
+    Use option `-N` to not using fuzzy matching when an exact match is not found.
 
-	3.3 if you already have PO-file created before and new PO-file created from new sourse files
-	    which is not related with first one, you have to concatenate old PO-file with
-	    strings from new PO-file. You can do that with command:
-		msgcat -o new.po old.po
+5.  To concatenate old PO-file with strings from new PO-file use command:
+    ```
+        msgcat -o new.po old.po
+    ```
 
-	4.  create an English translation catalog with command:
-		msgen -o new.po old.po
-	    Notice, in this Catalog it will be totally same strings for initial text and translated.
+6.  Create an English translation catalog with command:
+    ```    
+        msgen -o new.po old.po
+    ```
+    Notice, in this Catalog it will be totally same strings for initial text and translated.
 
 When you have Catalog to translation open POT or PO file in PoEdit and start to translation.
 It's very important to keep attention to every gaps and punctuation. Especially with