How to enable KEPUB kerning for sideloaded fonts

[GeoffR]

Until now all of the sideloaded fonts containing kerning tables that I had tried, whether OTF or TTF, functioned as expected in the EPUB reader but remained unkerned in the KEPUB reader.

But I found that converting the font to TTF in Fontforge with the "Old style kern" option enabled allows the kerning to work in the KEPUB reader too.

For example, I tried the Charta font from this thread with the KEPUB reader on my Glo (firmware 3.13.1), the first screenshot is with the font in OTF format, the second converted to TTF with the "Old style kern" option enabled:

[PremaEbooks]

Thanks!!

I have to try this.
In Spain we don't use double/single quotes for dialogs, instead we use "em dashes" and it's very annoying to see how those "em dashes" separate from the word when I have full justified text(it's the usual way of reading text in Spain, and I CAN'T read with left aligned text ).

Just to make it clear:

"I see you haven't done what I asked you to" Steve said.
"I have no intention to do what you ask me to" replies Frank "It's your fault expecting that from me".

In Spanish that would be:

—I see you haven't done what I asked you to —Steve said.
—I have no intention to do what you ask me to —replies Frank—. It's your fault expecting that from me.

But in kepubs, when the text is justified, it usually ends like this:

— I see you haven't done what I asked you to — Steve said.
— I have no intention to do what you ask me to — replies Frank —. It's your fault expecting that from me.

Those blanks between the "em dash" and the word drive me crazy XDDD
And for now I've just used the system fonts
I wonder if this could fix the problem.

It would be easier to read just simple epubs, but Kepubs gives me that "extra" with all the statistics

Note: I simply remame xxx.epub to xxx.kepub.epub and fix the issue with the cover. But internally the file is the same.
Indeed this doesn't happen in Kindle.
I also dissable hyphenation. It doesn't do a good job with spanish language

[GeoffR]

Originally Posted by PremaEbooks

But in kepubs, when the text is justified, it usually ends like this:

— I see you haven't done what I asked you to — Steve said.
— I have no intention to do what you ask me to — replies Frank —. It's your fault expecting that from me.

I don't think that is a kerning issue, it seems to be a separate bug in the kepub reader. It affects ellipses and other non-ascii punctuation too, adding unwanted space between the punctuation and the following letters, and upsetting the right justification. I don't know any way to avoid it other than to sideload the book as an epub instead.

Edit: mdash used as a quotation mark is a different issue, that is a publisher error. The mdash is a line break point; a proper quotation dash (unicode U+2015) should be used instead of a mdash (unicode U+2014) for quotation. Both kepub and epub readers handle this correctly: they will both allow a line break between an mdash and a letter, but not between a quotation dash and a letter.

[GERGE]

There are many more problems we won't be able to fix ourselves. Ligatures, hyphenation. Lack of ligatures is especially disturbing in side-loaded fonts. Looks really bad.

[PremaEbooks]

Originally Posted by GeoffR

I don't think that is a kerning issue, it seems to be a separate bug in the kepub reader. It affects ellipses and other non-ascii punctuation too, adding unwanted space between the punctuation and the following letters, and upsetting the right justification. I don't know any way to avoid it other than to sideload the book as an epub instead.

I was wishing it was...

Edit: mdash used as a quotation mark is a different issue, that is a publisher error. The mdash is a line break point; a proper quotation dash (unicode U+2015) should be used instead of a mdash (unicode U+2014) for quotation. Both kepub and epub readers handle this correctly: they will both allow a line break between an mdash and a letter, but not between a quotation dash and a letter.

Thanks for the hint, but that is even worse. It's not a proper "long dash" is sorter and it keeps separated from the word.
All the epubs are built by myself and the only reader that does this is Kobo with kepubs and Sony T1 with simple epubs.

Kindle preserve those two glyphs together, I have them all, and I have tested this in all of them. Even the apps, on Android or iPad or even PC/Mac do the job perfectly.
It's only an issue in kepubs. It doesn't happen with the exact same file as xxx.epub. But I like ACCESS renderer because it implements some CSS3 and all the extra statistics.
It's a shame, but this is a bug in ACCESS.
Something similar happens with hyphens. The same file as xxx.epub breaks the words in the right place while as xxx.kepub.epub breaks the word in order to fit the width... which ends as a total disaster


Anyway... thanks a lot for your help

[PremaEbooks]

Originally Posted by GERGE

There are many mode problems we won't be able to fix ourselves. Ligatures, hyphenation. Lack of ligatures is especially disturbing in side-loaded fonts. Looks really bad.

I agree with that... But one of the reasons why some fonts are available with the system a not any other the user can sideload, could be based on some things that could happen with "special" books. Some books (I rembember the last one I built, both print and ebook) had "special symbols". Based on my tests I could not find a problem with system fonts, but it could happen with sideloaded fonts.

You can force the font in that particular book so the user can not use another one, but I prefer to let them choose the available fonts in every device... I love serif fonts, some people love sans... there's no need to force someone to read with a font he/she doesn't like... as long as the system fonts have those glyphs.

After 8 years dealing with ebooks I have something clear: there's never goning to be a "one size fits all" solution. Because we all think differently

[GeoffR]

Originally Posted by PremaEbooks

Thanks for the hint, but that is even worse. It's not a proper "long dash" is sorter and it keeps separated from the word.
All the epubs are built by myself and the only reader that does this is Kobo with kepubs and Sony T1 with simple epubs.

Sorry I didn't mean to imply that the quotation dash would avoid the kepub bug that adds extra space after some punctuation. But it does avoid another problem with using an mdash as a quotation dash, that of the reader treating the dash as a line break point.

The actual size and bearing of the quotation dash will be defined by the font you use, and with the kepub reader if the font lacks a quotation dash then it will substitute one from another font, which might not match the size of the mdash in the current font.

The screenshots attached show the difference between a quotation dash and an mdash, using the Amasis font in the epub reader (it works the same in the kepub reader except for the punctuation/justification bug) -- both readers allow a line break after the mdash, but not after the quotation dash:

(But in the end, if you want good typography then you need to sideload the book as an epub and use the epub reader. The kepub reader has some extra features like stats and image zoom, but it fails at basic stuff like justification, hyphenation, word spacing, etc.)

[PremaEbooks]

Thanks, again, GeoffR

The problem, as you say, is ACCESS.
Even not having that "white space" between the word and the em dash this renderer does separate them. And the bigger the font the worse...

It happens not matter which font I use. Indeed I use Amasis and Caecilia the most
Is there any way to make a screenshot without patching?

[PeterT]

Screenshot does not need a patch; it just needs a line (or two) to be added to the Kobo eReader.conf file.

[FeatureSettings] 
Screenshots=true

This file is found in the .Kobo\Kobo directory of your device.

Be sure to edit with an editor that is aware of Unix style end-of-line conventions. (Using Windows, Notepad++ is an excellent choice).

If there is NO [FeatureSettings] section add both lines, otherwise just add the one line Screenshots=true after the [FeatureSettings].

After this change has been made, the power button will take a screen shot. To power the device off simply remove the line Screenshots=true.

[PremaEbooks]

Originally Posted by PeterT

Screenshot does not need a patch; it just needs a line (or two) to be added to the Kobo eReader.conf file.

[FeatureSettings] 
Screenshots=true

This file is found in the .Kobo\Kobo directory of your device.

Be sure to edit with an editor that is aware of Unix style end-of-line conventions. (Using Windows, Notepad++ is an excellent choice).

If there is NO [FeatureSettings] section add both lines, otherwise just add the one line Screenshots=true after the [FeatureSettings].

After this change has been made, the power button will take a screen shot. To power the device off simply remove the line Screenshots=true.

Ok!
Thank you!
I applied the patch but only to set some things that I like best. In my "speedy reading" I mixed things and I didn't remember if screenshots were part of the patch. I have a cover that could help me wake the reader up, so no need to remove that line...
Yep, I use Notepad++

In Kindle PW 1&2 you can get screenshots by touching the opposite corners of the screen.

[isaacbh]

Is there a way to enable ligatures? Do they work in the epub reader?

[GeoffR]

Originally Posted by isaacbh

Is there a way to enable ligatures? Do they work in the epub reader?

The EPUB reader uses ligatures, if the font has any. I haven't seen any sign that the KEPUB reader does.

(Look at the screenshot in my post above. The epub reader used an fi ligature in billfish.)