Qusay, do you refer to Kdenlive's titler for creating title clips?

Qusay, is character spacing set to 0 or another value? Can you work around the issue by decresing the character spacing below 0? Please be so kind as to report back. Thank you very much for your cooperation.

Please supply information.

(In reply to Wegwerf from comment #2)
> Qusay, is character spacing set to 0 or another value? Can you work around
> the issue by decresing the character spacing below 0? Please be so kind as
> to report back. Thank you very much for your cooperation.

Yes I put character spacing set to 0

and here is another example http://imgur.com/a/BRu9y
It should by as thiis (by GIMP) : http://imgur.com/a/LAv3h

Tested Windows version:
The letter spacing should be increased, and that depends on the font it self. But it doesn't solve the problem 100% complete.
The text while editing is correct and doesn't have breaks in it. It just have breaks when it's painted to be used and not edited (clicking on the background of the text clip dialog, for example)
Sample text: "تجربة لنص عربي"

Maybe this [1] is the related slot, but not sure what's the problem there.

1: https://cgit.kde.org/kdenlive.git/tree/src/titler/titlewidget.cpp?id=8e054c9a5205650ffd05d1f5725ff3a39290ab54#n1609

The titler needs to render the characters as a single QString, otherwise Qt cannot apply its text shaping algorithms. Rendering characters individually will break not only Arabic, but also many Brahmi scripts.

Thank you sll for the information. This then would break also ligatures and kerning in western languages too.

More investigation:
It's not a problem with Arabic or western, it's a problem with overlapping line segments.
For example, applying the underline attribute to a pure English text inverses the "filling" in the characters.
For Arabic, the letters aren't spaced (it's the usual and correct look), but there are overlapping shapes (which is normal) whenever two letters are "connected" together.
That's why the curve shape at one edge of the break appears, that's how the letters are made and designed in fonts.

Check: http://i.imgur.com/5Zi45vb.png (Ligatures and kerning is working fine)
Arabic text in edit mode: http://i.imgur.com/4tnefCx.png (It's the same text but doesn't have that empty areas)

Please try with the actual Kdenlive version 18.08.2

Hi, can you test latest version and see if you can still reproduce?

Dear Bug Submitter,

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This bug has been in NEEDSINFO status with no change for at least
30 days. The bug is now closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
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I still have the bug in Kdenlive 22.04.0.
The bug is in the titler, and it happens with every font that has overlapping segments, as Safa Alfulaij said in comment 8.
When editing text in the title clip everything seems smooth, but then the video shows inverted color where the text segments overlap.

One fonts that clearly shows the problem is Segoe Script.

I guess it's similar to Bug 439659. Try with the AppImage 21.12.3 to see if it solves the problem.

(In reply to emohr from comment #15)
> I guess it's similar to Bug 439659. Try with the AppImage 21.12.3 to see if
> it solves the problem.

Thank you emohr for your reply, but why should an earlier release solve my problem?

Sorry, I have now read Bug 439659 and now I understand your proposal.

I tried with AppImage 21.12.3: it actually works correctly!!

Everything was perfect until I tried to render: unfortunately the rendering process crashes with this error:
/usr/bin/melt: /tmp/.mount_kdenliDWCYjf/usr/lib/libmlt-7.so.7: version `MLT_7.0.0' not found (required by /usr/bin/melt) /usr/bin/melt: /tmp/.mount_kdenliDWCYjf/usr/lib/libmlt-7.so.7: version `MLT_0.8.8' not found (required by /usr/bin/melt)

So, let alone the problem with the AppImage and the libmlt-7 library, what is the problem with the native Kdenlive package in Opensuse Tumleweed?

Do you get this crash rendering with the AppImage? It looks like MLT is not on the minimum version needed (version 7.0 or newer). 

If you rendered with the AppImage please check if the paths are set correct. Goto settings -> configure Kdenlive -> environment. See the settings for the AppImage here: https://docs.kdenlive.org/de/user_interface/menu/settings_menu/configure_kdenlive.html#mlt-environment

Created attachment 148483 [details]
kdenlive appimage settings

(In reply to emohr from comment #19)
> Do you get this crash rendering with the AppImage? It looks like MLT is not
> on the minimum version needed (version 7.0 or newer). 

Yes, I got the crash with the AppImage

> If you rendered with the AppImage please check if the paths are set correct.
> Goto settings -> configure Kdenlive -> environment. See the settings for the
> AppImage here:
> https://docs.kdenlive.org/de/user_interface/menu/settings_menu/
> configure_kdenlive.html#mlt-environment

My settings are the same as those indicated in the link you posted, but for the melt executable. The link you posted indicates /usr/local/bin/melt-7, mine is /usr/bin/melt (which is a symlink to /usr/bin/melt-7).
See attached screenshot in Comment 20.