Display issues of dead leading or trailing (unicode) characters

[spywhere]

Some languages contain characters that floating above/below another character such as Thai. Currently, Sublime Text (both 2/3) have this issue as you can see here...

• [http://sublimetext.userecho.com/topic/117587-thai-language-issue/](Thai language issue)
• [https://www.sublimetext.com/forum/viewtopic.php?f=3&t=11166](Thai alphabet have problem in Sublime)
• [https://www.sublimetext.com/forum/viewtopic.php?f=3&t=16314](Fail on thai font)
• [http://www.sublimetext.com/forum/viewtopic.php?f=3&t=8108](support for other languages?)

The issue is Thai words should be display like this

Rather than this

Proper fixing this helps our eyes to work a lot easier.

PS. In case you want the sentences above for testing on your own copy. Here...

แล้วสอนว่าอย่าไว้ใจมนุษย์
มันแสนสุดลึกล้ำเหลือกำหนด
ถึงเถาวัลย์พันเกี่ยวที่เลี้ยวลด
ก็ไม่คดเหมือนหนึ่งในน้ำใจคน


แม้นใครรักรักมั่งชังชังตอบ
ให้รอบคอบคิดอ่านนะหลานหนา
รู้สิ่งไรไม่สู้รู้วิชา
รู้รักษาตัวรอดเป็นยอดดี

[FichteFoll]

Screenshot on Win7 with Consolas font:

Just to confirm this issue on OS X 10.9.5, with more than one monspaced font. Using a non monospaced font like "Arial" or "Verdana" I get a correct result, the same result as @FichteFoll (but not with Consolas).

Pasting @spywhere's example in another text editor with same font as ST (DejaVu Sans Mono) outputs the correct result.

[willbeaufoy]

I have the same issue on Sublime Text 3 build 3083 on Ubuntu 15.04.

In terminal and all other apps I've tried, I'm able to insert combining characters by typing a letter, then ctrl+shift+u to enter unicode entry mode, then the combining character code, (e.g. 0304 for overline), resulting in something like this: x̄.

However in sublime text, doing the same thing (using ctrl+alt+shift+u to enter unicode mode), leaves me with a dotted circle next to the character, with no way to remove this (if you delete the dotted circle the overline is also removed. However if you copy and paste the dotted circle and overline and paste it into the terminal it renders correctly. Also in ST the character itself seems the wrong size.

This occurs in non monospaced fonts like Calibri and Verdana, and in monospaced ones like DejaVu Sans Mono.

[titoBouzout]

A word of jon on this issue from https://forum.sublimetext.com/t/dev-build-3098/16706/26?u=tito

Sublime Text < 3096 didn't support grapheme clusters at all, and 3096 introduced support for some Legacy Grapheme Clusters (i.e., base code point followed by 0 or more combining codepoints), but not support for Extended Grapheme Clusters. More details are at http://unicode.org/reports/tr29/#Grapheme_Cluster_Boundaries3

[wbond]

@willbeaufoy On OS X, I can confirm that build 3112 properly renders combing characters, per the example you gave.