Version 24 of Arabic Character Renderer For Readability In TCL/Tk

Updated 2013-07-03 12:50:07 by Superlinux

This is a working solution
هذا حل فعلا يعمل و هو سهل الاستعمال
The following procedure render_arabic does not completely solve the rendering the Arabic characters to be fully connected.
However, it does reach the wanted target and goal of making the Arabic smoothly readable.
So you can now type in the code as such:

set arabic_rendered_sentence [ render_arabic "مرحبا بكم"]

Then get in your Tk something very near to the following result.
Please just understand I am using the text to explain and imagine it with the spaces are just only one millimeter wide.

مـ ر حـ بـا بـ كم

Download the script here

This video on YouTube explains how it works from within the code:
Render Arabic Language Words in TCL and Tk (Video Take 2)

If you are planning to do inputs, then do the following steps:

     set list_of_widget_window_paths [list .mytext1 .anotherText2 .toplevel.toplevel_text]
  • Then you must bind all of the text widgets as follows:
 foreach text_widget_window_path $list_of_widget_window_paths {
 bind $text_widget_window_path <Key> [list text_binding_for_rtl %W %k]
}

And you're done!

See it in action here:
Render Arabic Language Words in TCL and Tk (Video Take 3)


The Required Procedures

The script to render_arabic $arabic_string

A procedure to make Arabic readable when displayed in a Tk widget.

#!/usr/bin/wish

#Code written by Rani Fayez Ahmad (Superlinux)
#Website: http://www.superlinux.net

#a procedure to make Arabic readable when displayed in a Tk widget.
proc render_arabic { arabic_string } {
    

    #The given of the problem is an Arabic sentence
    
    #Break the sentence into words
    set  words [ split $arabic_string ]
    
    #Display the sentence they TCL receives it
    #The problem is:
    #TCL receives the Arabic letters: (i) in the reverse order (ii) disconnected
    #we want to re-render the Arabic to be displayed correctly
    #tk_messageBox -message $words
    
    #$count is the word index in the Arabic sentence   
    set count 0
    
     #the following is just an example of how to get an arabic character index number in the unicode character charts
     #set z {} ; foreach el [split "لـ" {}] {puts  [scan $el %c]}
     
     #foreach word in the Arabic sentence 
    foreach word $words {
        
       
        #if the currently processed word is completely a Latin/russian/Greek or in another meaning completely an ASCI word, 
        # simply skip this word and move to the next. we only want to find Arabic words completely
        
        if {[string is ascii $word]==1} {
        incr count
        continue
        } 
        
        #1-get the  sub-string in the word without the last letter
        #we will deal with the connection of the last letter later
        set sub_word [string range $word 0 end-1]
        
        #All the letters from baa2 to yaa2 when they are NOT the last letter;
        #TCL initially has and reads them in their isolated form as in ل م س;
        #they must be converted into their initial form e.g لـ مـ سـ
        #so replace and convert every occurrence of each of such letters 
        set sub_word [ string map {"\u0628" \ufe91} $sub_word] ;#ba2 ب
        set sub_word [ string map {"\u062A" \ufe97} $sub_word] ;#Ta2 ت
        set sub_word [ string map {"\u062B" \ufe9b} $sub_word] ;#thaa2 ث
        set sub_word [ string map {"\u062C" \ufe9f} $sub_word] ;#Jeem ج
        set sub_word [ string map {"\u062d" \ufea3} $sub_word] ;#7aa2 ح
        set sub_word [ string map {"\u062e" \ufeA7} $sub_word] ;#5aa2 خ
        set sub_word [ string map {"\u0633" \ufeb3} $sub_word] ;#seen س
        set sub_word [ string map {"\u0634" \ufeb7} $sub_word] ;#sheen ش
        set sub_word [ string map {"\u0635" \ufebb} $sub_word] ;#SSaad ص
        set sub_word [ string map {"\u0636" \ufebf} $sub_word] ;#DDhahd ض
        set sub_word [ string map {"\u0637" \ufec3} $sub_word] ;#TTaa2 ط
        set sub_word [ string map {"\u0638" \ufec7} $sub_word] ;#tthaa2 Zah ظ
        set sub_word [ string map {"\u0639" \ufeCb} $sub_word] ;#3eyn ع
        set sub_word [ string map {"\u063A" \ufeCF} $sub_word] ;#ghyn غ
        set sub_word [ string map {"\u0641" \ufeD3} $sub_word] ;#faa2 ف
        set sub_word [ string map {"\u0642" \ufeD7} $sub_word] ;#quaaf ق
        set sub_word [ string map {"\u0643" \ufeDb} $sub_word] ;#kaaf ك
        set sub_word [ string map {"\u0644" \ufedf} $sub_word] ;#lam ل
        set sub_word [ string map {"\u0645" \ufee3} $sub_word] ;#meem م
        set sub_word [ string map {"\u0646" \ufee7} $sub_word] ;#noon ن
        set sub_word [ string map {"\u0647" \ufeeb} $sub_word] ;#haa2 هـ
        set sub_word [ string map {"\u064A" \ufef3} $sub_word] ;#yaa2 ي
        set sub_word [ string map {"\u0626" \ufe8b} $sub_word] ;#hamza 3ala nabera (initial form of yaa2) ئـ
        
        #now replace the whole part of the word that excludes the last letter
        #with the conversion done above
        
        set word [string replace $word 0 end-1 $sub_word]
        
        #The following list of characters are the characters initial form mentioned above + the tatweel character
        set initials [list \u0640 \ufe90 \ufe97 \ufe9b \ufe9f \ufea3 \ufeA7 \ufb3 \ufeb7 \ufebb \ufebf \ufec3 \ufec7 \ufeCb \ufeCF \ufeD3 \ufeD7 \ufeDb \ufedf \ufee3 \ufee7 \ufeeb \ufef3]
        
     
        #find the character before the last.
        
        set before_last_char [ string index $word end-1 ]
        
        #for debugging purposes just print the character before the last.
        puts $before_last_char
        
        #and try to see if  the character before the last is an element of the list $initials defined in the previous line.
        #and if it's true, then convert the last character to it's final linked form
        #this way they will be joined
        if { [lsearch -ascii -inline $initials $before_last_char ] == $before_last_char } {
            
        #now get also last character
        set last_character [ string index $word end]
        
        #print it for debugging purposes
        puts $last_character
        
        #just to make sure that we we are matching correctly print the Unicode index number of the character
        puts [scan $last_character %c]
        
        #now convert the last character into its final linked form
                switch -- $last_character {
                 \u0627 {
                    #baa2
                    set word [ string replace $word end end \ufe8e ]
                }
                \u0628 {
                    #baa2
                    set word [ string replace $word end end \ufe90 ]
                }

                \u0629 {
                    #taa2 marbootta
                    set word [ string replace $word end end \ufe94]
                }

                  \u062A {
                    #ta2 maftoo7a
                    set word [ string replace $word end end \ufe96 ]
                }

                  \u062B {
                    #thaa2
                    set word [ string replace $word end end \ufe9A ]
                }


                \u062c {
                    #jeem
                    set word [ string replace $word end end \ufe9e ]
                    puts $word
                }

                  \u062d {
                    #7aa2
                    set word [ string replace $word end end \ufeA2 ]
                }


                  \u062e {
                    #5aa2
                    set word [ string replace $word end end \ufea6 ]
                }

                  \u062f {
                    #dal
                    set word [ string replace $word end end \ufeaa ]
                }

                  \u0630 {
                    #tthal
                    set word [ string replace $word end end \ufeac ]
                }

                  \u0631 {
                    #raa2
                    set word [ string replace $word end end \ufeae ]
                }
                  \u0632 {
                    #zyn
                    set word [ string replace $word end end \ufeaf ]
                }

                  \u0633 {
                    #seen
                    set word [ string replace $word end end \ufeb2 ]
                }


                  \u0634 {
                    #sheen
                    set word [ string replace $word end end \ufeb6 ]
                }

                  \u0635 {
                    #ssaad
                    set word [ string replace $word end end \ufeba ]
                }

                  \u0636 {
                    #ddaad
                    set word [ string replace $word end end \ufebe ]
                }

                  \u0637 {
                    #ttaa2
                    set word [ string replace $word end end \ufec2 ]
                }
                  \u0638 {
                    #tthaa2
                    set word [ string replace $word end end \ufec8 ]
                }

                  \u0639 {
                    #3ayn
                    set word [ string replace $word end end \ufeca ]
                }

                  \u063a {
                    #ghyn
                    set word [ string replace $word end end \ufece ]
                }

                  \u0641 {
                    #faa2
                    set word [ string replace $word end end \ufed2 ]
                }

                  \u0642 {
                    #quaaf
                    set word [ string replace $word end end \ufed6 ]
                }
                  \u0643 {
                    #kaaf
                    set word [ string replace $word end end \ufeda ]
                }
                  \u0644 {
                    #laam
                    set word [ string replace $word end end \ufede ]
                }

                  \u0645 {
                    #meem
                    set word [ string replace $word end end \ufee2 ]
                }

                  \u0646 {
                    #noon
                    set word [ string replace $word end end \ufee6 ]
                }
                  \u0647 {
                    #haa2
                    set word [ string replace $word end end \ufeea ]
                }

                  \u0648 {
                    #waaw
                    set word [ string replace $word end end \ufeee ]
                }
                \u0624 {
                    #waaw with hamza above
                    set word [ string replace $word end end \ufe86 ]
                }

                  \u0649 {
                    #alef maqsura
                    set word [ string replace $word end end \ufef0 ]
                }

                  \u064a {
                    #yaa2
                    set word [ string replace $word end end \ufef1 ]
                }
                default {
                    #default is nothing to do
                }
            }
     
      }   ;# end of if the character before the last is a member of the list $initials
        
        #now reverse the word for correct displaying on the screen
        set word [ string reverse $word]
        
        #add and replace the corrected/conversion-of word with malformed one. in the Arabic sentence
        #the whole words in the sentence yet are still in the reverse order
        lset words $count $word
        
        #move to the  next word
        incr count
     
         
    }
    #reverse the order of the  list of words of the Arabic sentence and join them into one string.
    set words [join [ lreverse $words] ]
    
    #The following line is left for you to see the final result. just remove the comment sign (#)
    #tk_messageBox -message $words
    return  $words 
    
}

#The following is for testing the [proc render_arabic]
#the Arabic sentence means in English : 
#The program is not available or changeable (it should be here the word "NOT" (غير) instead of "CHANGEABLE" (متغير) but for debugging purposes there's an additional character) exists/existed 
set msg [render_arabic "الـبـرنـامـج غـيـر مـتـوفـر او مـتـغـيـر مـوجـود حـالئـيـا"]

tk_messageBox -detail $msg

The script of procedure text_binding_for_rtl $text_widget_path $k

This procedure will eventually call the procedure render_arabic $arabic_string .

proc text_binding_for_rtl {text_widget_path k} {
#Caution!!! *DO NOT* delete the next line of [set event_counter 0] . 
set event_counter 0
proc local_text_binding_for_rtl {text_widget_path k} {

  #Algorithm:
  #%k is the keycode number (%k is an integer not a hexadecimal) of the pressed key.
  #we print it for correct matching and selection of the keys being pressed.
  #If the %k is neither the space bar or the Enter don't process anything.
  #We only want to process the very last word.
  #And the Enter or the Space bar are the triggers and the signals just to say we have a new word being written in the entry.
  #Therefore, extract the last word. The last word must be checked to see whether it's completely an ASCII(Latin) string. 
  #If it's, then don't touch it and skip to the next word
  #Always keep the Latin/ASCII words as they are.
  #Else, process the word as an Arabic word using the procedure [render_arabic] defined above
  #Also map the last word to the rest of the text widget string just to save time
  
  puts "k= $k"
  global event_counter
  #Only Key-Enter  and Key-Space ban allow the processing of the last word
  if { $k != 65 && $k != 36 } {
    set event_counter 0
    return 
  } else {
 
   incr event_counter
     
  
    
  }
  
  #get the whole text as one string
  set all_text [$text_widget_path get 1.0 end] 
  
  #if the text is empty or full of so many spaces, then return doing nothing
  set trimmed_text [string trim $all_text]
  if { $trimmed_text =="" } {    
    return
  }
  
  
  
  
if { $event_counter ==1 } {
  #after trimming white spaces from both ends of the whole text ,
  #convert the text into a list of words to find the last word in the text
  set words [split [string trim $all_text] ]
  
  #for the sake of debugging and monitoring , print the list of words.
 puts $words
 
 #get the last word
 set last_word [lindex $words end ]
 
 #print the last word for debugging.
 puts $last_word
 
 #the word is completely ASCII, skip to the next word by quitting this event
    if {[string is ascii $last_word]==1} {
       
        return
        }  
   
 #we render the last word, which is supposed to be an Arabic word
     set last_word_after_rendering [render_arabic $last_word] 
    
    #print the last word after rendering for debugging
    puts $last_word_after_rendering
    
    #replace every occurrence of the original last word with the last word after rendering in all the text
    #but because it everything is already rendered but the last word, it will be only a replacement of the last word with 
    #the last_word_after_rendering
    set all_text [ string map [split "$last_word $last_word_after_rendering"] $all_text]
    set all_text "[string trimright $all_text] "
    #and finally re-assign the text again to the entry or text widget
    $text_widget_path replace 1.0 end $all_text 
}
}

local_text_binding_for_rtl $text_widget_path $k
}