Bug 66577 - Spell check change letter-spacing on Mac OS, up to compromising text editing
Summary: Spell check change letter-spacing on Mac OS, up to compromising text editing
Alias: None
Product: LibreOffice
Classification: Unclassified
Component: Writer (show other bugs)
(earliest affected) rc
Hardware: Other macOS (All)
: highest major
Assignee: Not Assigned
Whiteboard: BSA target:4.2.0 target:4.1.1
Keywords: regression
: 70424 70903 71337 72860 (view as bug list)
Depends on:
Blocks: mab4.1
  Show dependency treegraph
Reported: 2013-07-04 08:31 UTC by retired
Modified: 2014-05-03 17:38 UTC (History)
9 users (show)

See Also:
Crash report or crash signature:

test-document (writer) (13.77 KB, application/vnd.oasis.opendocument.text)
2013-07-04 08:31 UTC, retired
displaced curser screenshot (16.99 KB, image/png)
2013-07-04 08:40 UTC, retired
Ugly hack (1.60 KB, patch)
2013-07-13 20:39 UTC, ⁨خالد حسني⁩
Calc screen shot showing out of place cursor. (9.69 KB, image/png)
2013-08-01 00:21 UTC, CFraser
calibri font, cursor moves ahead of writing (1.66 MB, video/mp4)
2013-10-13 12:43 UTC, retired
Screen Copy of spellcheck-textwidth bug on macOS (36.35 KB, image/gif)
2013-11-07 13:18 UTC, Bernard Mendiburu
activating spell check changes the text size on MacOS (18.68 KB, image/gif)
2013-11-28 16:11 UTC, Bernard Mendiburu
Wrong cursor position in text (selection is highlighted) (18.12 KB, image/png)
2013-12-27 13:19 UTC, Cosmin Saveanu

Note You need to log in before you can comment on or make changes to this bug.
Description retired 2013-07-04 08:31:28 UTC
Created attachment 82012 [details]
test-document (writer)

Problem description: In Attached document the curser is not moving along with the written text correctly when typing. It get's moved to far and is thus displayed the longer a line gets.

Also when marking text the placement of the marked area is not matching the text that is acutally selected. I guess this derives to the same cause.

This happens when in View > Webview. This does not happen when in print-layout.

Steps to reproduce:
1. Open attached document
2. type something, and observe the cursor placement
3. also try marking text here and there and play with copy paste

Current behavior: see above

Expected behavior: correct cursor placement when using writer
Operating System: Mac OS X
Version: rc
Comment 1 Jorendc 2013-07-04 08:39:27 UTC
I can confirm this behavior using Mac OSX 10.8.4 with LibreOffice Version: Build ID: 9ab800829b8a0e44824dc11276b54b1870bc5b2b

@Khaled, Tor: Ping :). Don't know 'cursor placement' is related to CoreText? Thanks for your time!

Kind regards,
Comment 2 retired 2013-07-04 08:40:08 UTC
Created attachment 82013 [details]
displaced curser screenshot
Comment 3 Jorendc 2013-07-04 08:41:36 UTC
Not reproducible using Mac OSX 10.8.4 with LibreOffice So looks CoreText related to me.
Comment 4 retired 2013-07-04 08:52:48 UTC
Not sure if this is the same issue: https://bugs.freedesktop.org/show_bug.cgi?id=63993

If so it would be all platforms. Calibri seems a good testing font, since in 63993 on Linux it was used for testing as well.
Comment 5 ⁨خالد حسني⁩ 2013-07-04 11:07:59 UTC
I can not reproduce this, either I’m too lucky or you guys too unlucky, that is the third Mac bug I can not reproduce today.
Comment 6 ⁨خالد حسني⁩ 2013-07-04 11:11:20 UTC
Aha, I think I can reproduce this now. It is only reproducible if spell checking is enabled, something i going wrong in here.
Comment 7 Emir Sarı 2013-07-04 11:23:03 UTC
It looks like witchcraft. Guys, what did you hide in code? :)
Comment 8 ⁨خالد حسني⁩ 2013-07-12 16:33:22 UTC
I debugged this a bit and the issue is limited to the Web Layout, so IMO it shouldn’t be a release blocker.

The wrote cause is that SwFntObj::DrawText() uses the glyph widths array returned by OutputDevice::GetTextArray() (which in turn calls CTLayout::FillDXArray()) to calculate character positions/text width, and all are integer based while Core Text is floating point based and can return fractional glyph widths, so we end up with accumulated rounding errors that manifests in this issue (and probably bug 65971 as well).

Right now I have no idea how to fix this.
Comment 9 Michael Meeks 2013-07-12 19:49:04 UTC
I wonder if accumulating the error from the last character in some horrible global static float - and adding it to the next one would work ? ;-)
Comment 10 ⁨خالد حسني⁩ 2013-07-13 20:39:09 UTC
Created attachment 82393 [details]
Ugly hack

Here is an ugly hack to distribute the rounding errors at word boundaries and also make sure calculating text width is always correcting, I tested it only briefly and it probably breaks something else.
Comment 11 Commit Notification 2013-07-15 10:22:40 UTC
Khaled Hosny committed a patch related to this issue.
It has been pushed to "master":


fdo#66577: Cursor displaced in Web Layout

The patch should be included in the daily builds available at
http://dev-builds.libreoffice.org/daily/ in the next 24-48 hours. More
information about daily builds can be found at:
Affected users are encouraged to test the fix and report feedback.
Comment 12 Commit Notification 2013-07-16 16:01:47 UTC
Khaled Hosny committed a patch related to this issue.
It has been pushed to "libreoffice-4-1":


fdo#66577: Cursor displaced in Web Layout

It will be available in LibreOffice 4.1.1.

The patch should be included in the daily builds available at
http://dev-builds.libreoffice.org/daily/ in the next 24-48 hours. More
information about daily builds can be found at:
Affected users are encouraged to test the fix and report feedback.
Comment 13 retired 2013-07-19 10:26:37 UTC
Still happening in LO But from what I read, Khaled did fix this. Thanks a lot! :)

So waiting for 4.1.1 and setting to Resolved, Fixed.

@Khaled: Would that mean that https://bugs.freedesktop.org/show_bug.cgi?id=63993 should be fixed as well?
Comment 14 ⁨خالد حسني⁩ 2013-07-19 11:32:17 UTC
This isn’t fixed yet. The last commits lessen the rounding errors a bit, but the issue is still there.
Comment 15 CFraser 2013-08-01 00:21:09 UTC
Created attachment 83405 [details]
Calc screen shot showing out of place cursor.

Tried the 31st July nightly build and the particular Writer doc I had issues with now works, but Calc still has the issue.

Screen shot shows creating a spreadsheet and then starting to type... the text starts to resize in and out as you type and the cursor starts to get in the wrong position. This is same behaviour as the released 4.1 version.

OS X 10.7.5.

Comment 16 Don't use this account, use tml@iki.fi 2013-08-01 08:41:29 UTC
I am not suggesting it would be the proper "fix" for this bug, but still, just out of interest: How important is the "web layout" view actually? Personally I think we LibreOffice developers should be more brave in also *removing* seldom-used features that either 1) are buggy, or 2) introduce lots of complexity in the code (or both). Just my opinion.
Comment 17 tzunder 2013-09-17 08:26:10 UTC
LO Version:
Build ID: 89ea49ddacd9aa532507cbf8

OS X 10.8.4 (12E55)

Problem occurs in Print Layout.

Not evident in Open Office AOO400m3(Build:9702)  -  Rev. 1503704
2013-07-16 14:51:10 (Tue, 16 Jul 2013)
Comment 18 jessica 2013-10-08 20:49:18 UTC
I am working in MAC OSX.7.5 and LibreOfice In Print Layout I am experiencing the same cursor problem. It makes it almost impossible to type a document of any great length. Is there a fix?
Comment 19 retired 2013-10-13 12:37:27 UTC
*** Bug 70424 has been marked as a duplicate of this bug. ***
Comment 20 retired 2013-10-13 12:43:05 UTC
Tor: I disagree on this very much. Web Layout is my most used view. In times of digital documents, why at all would I want to work in page view? I don't plan on printing my documents so no need for page layout at all. Why would Web Layout be dropped if it is the format which might be most used in the future?

Also attaching a video of two related problems.

1) the cursor is on and even before some letters when typing.

2) the cursor moves in front of what is being typed when using the Calibri font.
Comment 21 retired 2013-10-13 12:43:48 UTC
Created attachment 87555 [details]
calibri font, cursor moves ahead of writing
Comment 22 alaw 2013-10-28 19:47:19 UTC
On a Mac 10.5.7, I have experienced this error where the cursor is not aligned with each character using Times New Roman.  When I switched to Times Roman, the problem disappeared.  Perhaps there is a font width error with Times New Roman but not Times Roman.
Comment 23 ⁨خالد حسني⁩ 2013-10-29 15:54:12 UTC
*** Bug 70903 has been marked as a duplicate of this bug. ***
Comment 24 retired 2013-11-07 10:53:16 UTC
*** Bug 71337 has been marked as a duplicate of this bug. ***
Comment 25 Bernard Mendiburu 2013-11-07 13:18:14 UTC
Created attachment 88821 [details]
Screen Copy of spellcheck-textwidth bug on macOS
Comment 26 Bernard Mendiburu 2013-11-07 13:18:56 UTC
This is a very tricky bug, and AFAIK, it's been present in other releases.
It's present when in WEB VIEW and with SPELL CHECK on.
It's actually very interesting to activate it and then toogle spellcheck on/off.

You then realise that the cursor is not at falt.
It's the text width that changes.
spellchecked text is sometimes displayed wider, sometime denser.

Will try to upload a screen grab.

Seems to be the spell checking affecting the display layout, but not the cursor.

Any clue ?

Note on fonts: Adobe Caslon can be wider/narrower, when Times New Roman is only wider with spell check on.
Comment 27 retired 2013-11-21 08:41:26 UTC
Upping to "major" since this prevents any productive work from happening in Web Layout.
Comment 28 Bernard Mendiburu 2013-11-28 16:11:34 UTC
Created attachment 89961 [details]
activating spell check changes the text size on MacOS

Screen Copy of spellcheck-textwidth bug on macOS ==>CALC<==
Comment 29 Bernard Mendiburu 2013-11-28 16:14:08 UTC
Just added attachement 89961
Shows the same bug in CALC
AFAIK, the bug is not present in IMPRESS and DRAW
Comment 30 Marcus Hudritsch 2013-11-28 16:21:04 UTC
I recognize this bug specially in IMPRESS.
Comment 31 Bernard Mendiburu 2013-11-29 12:53:17 UTC
(In reply to comment #30)
> I recognize this bug specially in IMPRESS.
> Regards
> Marcus

I did my best to replicate in IMPRESS and could not.
Can you post your procedure and/or a sample file.

I am using 
Build ID: 70feb7d99726f064edab4605a8ab840c50ec57a
On OsX 10.6.8 MacBookAir3,1
Comment 32 ⁨خالد حسني⁩ 2013-12-19 06:09:20 UTC
*** Bug 72860 has been marked as a duplicate of this bug. ***
Comment 33 Bernard Mendiburu 2013-12-19 10:29:25 UTC
Bug name just been changed 

VIEWING: Cursor displaced in Web Layout when misspelled text is highlighted 	

Cursor is sometimes misplaced when editing text on Mac OS X 

and that's not the accurate description.

The default is activated by enabling spellcheck in some viewing modes including WRITER Web View and CALC. It changes the displayed text length upon various unindentified parameters including text content and displayed font. 

Suggested COMMENT: 
The cursor stays at the same place as it would be with spellchech dis-activated, and is therefore not alligned with displayed text insert point when the bug is active. For this reason the bug is sometimes refered as "faulty cursor". Truth is, it is a text display bug. Enabling spellcheck should NOT change text layout. We suspect a letter spacing rounding error. 

Suggested TITLE:
"Activating spellcheck changes the letter-spacing on Mac OS"
ref: http://en.wikipedia.org/wiki/Letter-spacing

"mal nommer les choses, c'est ajouter au malheur du monde"
Albert Camus
Comment 34 Cosmin Saveanu 2013-12-27 13:19:08 UTC
Created attachment 91221 [details]
Wrong cursor position in text (selection is highlighted)

The problem disappears if I change the paragraph align to left instead of justified.
Comment 35 Cosmin Saveanu 2013-12-27 13:24:12 UTC
The title of this bug report looks accurate to me even if it might be not a single cause to the behaviour described by each and every user. 

Using LibreOffice on Mac OS X 10.9 (but having the same issue previously on 10.6.8), I found the same extremely annoying behaviour of the cursor. It is sometimes displaced from the position where the actual editing happens. In the uploaded picture, the actual selected character is "r" but the selection is between r and the previous letter. The problem magically disappears if the I change the paragraph alignment from "justified" to "left".

Could it be that the display position and cursor position are not linked ? When text changes slightly due to a different alignment requirement for the paragraph, it looks like the cursor does not know about it...

Please, please, some text positioning guru, notice this problem and help us with a solution!
Comment 36 Bernard Mendiburu 2013-12-27 18:57:55 UTC
Dear Cosmin and Fellows Bug Commenters,

If I may, I would like to insist on the fact that this is NOT a cursor bug.
The cursors is, stays, remains at the right position.
This is a *letter-spacing* bug that makes the text being improperly rendered when spell checking is activated.
I agree, you suffer from "cursor misbehavior" but, please, keep reading:

-1- Can we agree that "spell checking" should NOT change text rendering ?

Yes ? 
Then take you favorite "wrong cursor" file and toogle spell checking on and off.
Text rendering changes, OK ?
More accurately, line lengths changes, sometimes expand, somtimes contract.
This is the bug. 
Even if the cursor where behaving OK, we do not want the spell checking to wack our page desing.

-2- Now that's a spellcheck text rendring issue, what about the cursor.

Try this: 
- type aaaaaaaaaaaabbbbbbbbbbbb
- disactivate spellcheck
- place the cursor when you whant to inject text, between a and b
- activate spellcheck, 
- the cursor did NOT move on screen, even if the text did.
- insert text
- you get aaaaaaaaaainsertbbbbbbb

The bug does NOT move the cursor
The bug DOES move the text
The bug does NOT affect text insert logic

please accept my appologies for CAPPING:


As soon as the bug -1- is solved, the bug -2- is no longer present.

As we are helping programmers finding a bug, we should pay attention not to send them searching in the wrong piece of code.

Comment 37 Ivan 2014-02-11 23:07:56 UTC
Comment on attachment 91221 [details]
Wrong cursor position in text (selection is highlighted)

I can confirm this bug! For me it's really a critical bug. 
It is hard to edit a document, when the cursor position is wrong. It's a core functionality of a text editting software.
Comment 38 sophie 2014-02-12 09:45:38 UTC
Changed importance to reflect the new policy - Sophie
Comment 39 tommy27 2014-05-03 09:02:49 UTC
I'm a Window user so I cannot test, so please give me an update of the status of this issue with current LibO release or 4.3master

if bug is still there, move it to the mab4.2 list (Bug 65675)
if bug is gone set status to RESOLVED
Comment 40 retired 2014-05-03 17:38:00 UTC
No longer am able to reproduce this issue under LO and OS X 10.9.2.


Please test yourself and if you still are able to reproduce this most annoying behavior with or newer, make sure to re-open this bug and provide exact repro steps.