kobopatch users & non-Kobo-supported languages

[jackie_w]

A few days ago this post by Vetchy started me thinking a bit more about the day-to-day problems of Kobo users who's native language is not one of those currently supported by Kobo.

I have since spent a bit of time digging around in the GUI-related bits of the firmware, trying to understand it better. I've also tried to answer a few other language-related queries. Some of those were dictionary-related which is NOT what I want to discuss in this thread.

What I'd like to discuss here is the general Kobo GUI. The main problem appears to be that the 2 main Kobo system fonts Georgia (serif) and Avenir (sans-serif) are not well-suited to some languages, Avenir in particular. The default fallback font used when Avenir is inadequate (probably one of the CJK fonts) is not good either.

I'm going to assume that those of you who find the GUI unsatisfactory have at least managed to sideload one good font which makes reading your books tolerable. Otherwise you'd presumably have bought a better eink device by now, right?

If we wait for Kobo to package better unicode system fonts we may be waiting a long time - possibly licensing cost is an issue. So I'd like to see if there's anything we can do to improve things using your sideloaded 'good' fonts and the current kobopatch system.

There may not be a single "quick fix" so, what I'd like to know is, which parts of the GUI need early attention.
vostro here suggested the various Book lists would be a good start. This is your opportunity to have a say.

To make progress I will also need the help of experienced kobopatch users who are willing to beta test any new patch ideas and report back here in a "timely" manner. By "timely" I mean responding in <24hours, not weeks between posts.

There may not be a 100% perfect solution but I hope it's worth a try.

I wait to hear whether there are enough willing volunteers to get started.

Here is a summary of findings, post #63

[jackie_w]

I've paraphrased these notes from one of my posts in the kobopatch request thread. I may need to refer to them later in this thread.


Important general info about customising font-family in the Kobo GUI. It is particularly relevant to users who mainly read standard epubs rather than kepubs.

After a full reboot, as far the GUI is concerned, the Kobo only has immediate access to a limited number of its built-in fonts, Georgia, Avenir and possibly one or more of the CJK fonts. The rest of its built-in fonts and all your sideloaded custom fonts are only loaded "as necessary". I don't know the exact rules, only what I've observed.

After a full reboot I've always found that the following will force the Kobo to access all fonts. You won't have these problems if you only put the Kobo to sleep.

1. Open any kepub. It's as easy as that for users who only read kepubs.
2. If you open a standard epub and you don't see the custom font you were expecting (in the GUI not the book's text)
   • Press the [Aa] font menu button. You don't need to do anything else, just close it again.
   • If you still don't see the font, force the Kobo to re-render by paging across a chapter file boundary, then page back again. Or, closing the book and opening a different one might work, too.

N.B.: *** Update for firmware 4.21.15015+ ***

It is now possible to avoid having to do the above after every reboot. See the *** Update in the post #63 Summary for more details.

[geek1011]

reserved for myself

[vostro]

thanks a lot jackie for getting this start, i have forma, aura one and kobo H2O running latest patched version and am willing to test new patched version regarding to this feature and report back asap.

[jackie_w]

Originally Posted by vostro

thanks a lot jackie for getting this start, i have forma, aura one and kobo H2O running latest patched version and am willing to test new patched version regarding to this feature and report back asap.

Thanks for volunteering.

Can I ask:

• what is your native language?
• which sideloaded or built-in font(s) solve your book reading needs? Is it serif-only? sans-serif-only? a mix of the two?
• do you have other hacks installed to help with existing problems? If so, what are they?

[vostro]

after some test, only sideloaded CD2000 font solved the missing content in some dictionaries(the only hack I used is changing dictionary font). although kobo added trational chinese(which is my native language) in recent version, the booklist still has some missing content.

[jackie_w]

Originally Posted by vostro

after some test, only sideloaded CD2000 font solved the missing content in some dictionaries(the only hack I used is changing dictionary font). although kobo added trational chinese(which is my native language) in recent version, the booklist still has some missing content.

Oh dear, I wish I'd realised this sooner. Chinese and Japanese are treated as "special cases" throughout the GUI. Pages full of either look like rather attractive artwork to me, rather than the written word. I cannot recognise when things are badly wrong. If you add vertical text or right-to-left text into the mix I fear that is too ambitious for me at this point.

My hope was to try to start with simpler left-to-right horizontal languages, e.g. those who use the Cyrillic alphabet or perhaps Vietnamese.

Sorry to disappoint.

[vostro]

Originally Posted by jackie_w

My hope was to try to start with simpler left-to-right horizontal languages, e.g. those who use the Cyrillic alphabet or perhaps Vietnamese.

if you could just patch the UI font replaced by customized name assuming you could decrypt the related font name and path, it would be sufficient I guess. you don't need to recognize the correctness of content of text as that's tester's job.

[dmapr]

I think I can turn my Aura HD into a test device, assuming it'll take a charge, boot up and update — will get back on that. Can test Cyrillic. What I've done for it is side-load the version of Amasis from Nook. I'm really curious to see how that works since it's the same as the built-in one. I used to remove the built-in version but I no longer do that, so both co-exist.

[jackie_w]

@dmapr,

Thanks for responding. I used my old abandoned AuraHD for the same purpose.

I've attached a simple patch which works on the biggest CSS stream in nickel which handles all the basic GUI widgets. It will change all occurrences of Georgia and Avenir to use whatever sideloaded font(s) you specify in the patch.

N.B.: I have tried this myself so I don't think there's much risk involved (but still a good idea to test on a device you don't use much).

To begin with, it might be an idea to set up your kobopatch.yaml file so that this patch is the only one installed so as not to confuse matters.

After you've installed the patched KoboRoot.tgz, and the Kobo has rebooted don't be at all surprised if you don't see your new font on the Home screen. At least some of the Home screen widgets are not affected by this patch, they are in a different CSS stream. In addition, if you haven't already, please read post #2. You need to force the Kobo to load all its fonts (built-in and sideloaded).

Once you've done that, the best place to check whether it was successful is in the My Books book list. I believe most (all???) its widgets will be affected by the patch, if the patch has worked.



In this patch all the usual Kobo fontname rules apply:

• if the new name contains any spaces wrap it in single quotes,
  e.g. 'Kobo Nickel'
• the new name must match EXACTLY the internal fontname as seen in your font drop-down menu

Change the red bit to your new serif font of choice, but do not remove the ',Georgia' after it.
Change the blue bit to your new sans-serif font of choice, but do not remove the ',Avenir' after it.
If you want an easy life you could use your Amasis name for both the Replace strings. It would give the GUI a more uniform look.

Put in nickel.yaml (or wherever you normally put your customised nickel patches):

Custom GUI system fonts beta1:
  - Enabled: yes
  - Description: Change font-family of basic GUI widgets
  - FindZlib: "QWidget[smallIconHeight=true][qApp_deviceIsTrilogy=true]"
  - ReplaceZlibGroup:
      Replacements:
        - {Find: "font-family: Georgia;", Replace: "font-family:your_serif_name,Georgia;"}
        - {Find: "font-family: Avenir;",  Replace: "font-family:your_sans_name,Avenir;"}

[jackie_w]

Originally Posted by vostro

if you could just patch the UI font replaced by customized name assuming you could decrypt the related font name and path, it would be sufficient I guess. you don't need to recognize the correctness of content of text as that's tester's job.

Hi vostro, if you're still listening ...

I don't know enough about fonts to pursue replacing the physical system UI fonts. If you had asked me yesterday I would have said that it was not even possible because of their encryption. However, earlier today, someone posted elsewhere in the Kobo forums that they had done precisely that to fool the Kobo into thinking their hacked Arial font was Georgia so they could read Vietnamese.

I've done a bit more thinking about using kobopatch with the 'special case' Chinese font. I think it would be quite easy to create a patch very similar to dmapr's in post #10, but targeting the CSS for Chinese fonts rather than Georgia/Avenir.

Kobo's nickel CSS streams are packed with code similar to this (82 in fact):

DisplayLabel[localeName="zh"] {
  font-family: Sans-SerifZH-Traditional, sans-serif;
  font-style: normal;
}
DisplayLabel[localeName="zh-HK"] {
  font-family: Sans-SerifZH-Traditional, sans-serif;
  font-style: normal;
}
DisplayLabel[localeName="zh-TW"] {
  font-family: Sans-SerifZH-Traditional, sans-serif;
  font-style: normal;
}

I don't know which of the Chinese locales, "zh", "zh-HK", "zh-TW", your Kobos are set to but it wouldn't be difficult for me to adapt the post #10 patch to replace

font-family: Sans-SerifZH-Traditional, sans-serif;

with

font-family: CD2000, sans-serif;

in the CSS which handles the basic GUI widgets. This is assuming CD2000 is the correct name for your copy of Code2000. I mention this because my own download of Code2000 shows an internal filename of Code2000 not CD2000 and we must be precise if we do this.

I'm assuming, but don't know, that the 'sans-serif' fallback font above is Kobo's built-in 'Kobo UD Kakugo'.

My concerns are:

• As Kobo's CJK fonts are treated differently to other fonts, I don't know whether applying such a patch would do Very Bad Things. Only you can decide whether it's worth the risk. Do you have a Kobo you like less than the others?
• Why are Kobo referring to the built-in Chinese font as 'Sans-SerifZH-Traditional' rather than its real name of 'AR UDJingxihei'. They do something similar with the Japanese font. Just another example of them being treated differently to Georgia/Avenir.

Another, less risky, way forward would be for me to prepare a patch which only targets one small part of the GUI, e.g. the Book title in the My Books book list. We could try that as a first step if you want.

What do you think?

[vostro]

Originally Posted by jackie_w

Another, less risky, way forward would be for me to prepare a patch which only targets one small part of the GUI, e.g. the Book title in the My Books book list. We could try that as a first step if you want.

What do you think?

thanks a lot for the help, as i'm not sure if the bricked kobo could be revived without need of opening the case(with models what i have mentioned plus kobo aura which is not patched--they are all not easy to get case opened--and UI font i set should be zh-TW), i prefer less risky approach you said:"prepare a patch which only targets one small part of the GUI, e.g. the Book title in the My Books book list." thanks again.

[jackie_w]

Originally Posted by vostro

thanks a lot for the help, as i'm not sure if the bricked kobo could be revived without need of opening the case(with models what i have mentioned plus kobo aura which is not patched--they are all not easy to get case opened--and UI font i set should be zh-TW), i prefer less risky approach you said:"prepare a patch which only targets one small part of the GUI, e.g. the Book title in the My Books book list." thanks again.

Just so I'm 100% clear, you're saying you are prepared to risk patching a Kobo as long as its just a mini-patch targeted at only the Book list book titles?

You do accept that I still can't make any guarantees about what will happen? This is new ground for all of us.

[geek1011]

Originally Posted by jackie_w

Just so I'm 100% clear, you're saying you are prepared to risk patching a Kobo as long as its just a mini-patch targeted at only the Book list book titles?

You do accept that I still can't make any guarantees about what will happen? This is new ground for all of us.

But, note that almost everything can be fixed with a full reset (and everything with CSS patches can).

[vostro]

Originally Posted by jackie_w

Just so I'm 100% clear, you're saying you are prepared to risk patching a Kobo as long as its just a mini-patch targeted at only the Book list book titles?

You do accept that I still can't make any guarantees about what will happen? This is new ground for all of us.

thanks, as long as it could be fixed by full reset it's ok.