Does ugfx can display a chineese character?

[jayjiang]

Hi,

I upload a .ttf file which include chineese characters to online font converter, but I found it only converted a few characters(I've selected "no filter" option).

[Joel Bodenmann]

Hello jayjian and welcome to the community!

To your original post: Yes, uGFX supports chinese character rendering due to UTF-8 support. We also had at least one customer who successfully uses uGFX with chinese fonts in the past.

However, none of the uGFX developers knows chinese. Therefore, it is very difficult for us to verify that it is working properly. It seems like there are different "version" of chienese, with different encodings and even different alphabets. We already fail at the stage where we need to make sure that we got a font that can be used with a random sentence that we copied off the internet somewhere.

Anyway: We downloaded a random font and a random sentence and we definitely get something displayed. Whether that is proper chinese or not - we cannot say. The characters seem to match at least and provided the fact that a chinese customer used uGFX with chinese fonts without ever complaining should mean that it can uGFX can be used to handle chinese fonts.

We took some free TTF chinese font, uploaded it to the font converted, disabled the filter and got all the converted glyphs back. Seems to work so far on our side.

We are sorry that we can't really help you any better.

~ Tectu

[jayjiang]

thanks for replying my question!

[jayjiang]

1.For this question, I download the mcufont encoder' s source file and compile it into windows execute file. I found the offset table' s size is limited by 64KB. for Chinese character,is not enough. So may be you guys can check it again.

2.I wonder if I could display Chinese on widgets？

3.I want to display the file name(Chinese) which read from FatFs but FatFs will convert it from unicode to cc396(GBK). I must convert it to unicode then to UTF8 for display. So I want to know if ugfx can support UTF16(I know mcufont is support it, but ugfx' s widgets (e.g. list) is not support)？

[inmarket]

Currently any string handling in ugfx is based on 8 bit characters (ascii, utf8 etc).

Changing to 16 bit characters would require appropriate source code modifications.

If you would like to attempt this we would love the contribution.

I would suggest a new type called "gfxchar" whose definition is based on a gfxconf.h macro eg GFX_NEED_CHAR16.

[inmarket]

I will look at the offset table problem as soon as possible.

[jayjiang]

I ‘ve read the source code but I think I can't finish it in a short time. I simply use _LFN_UNICODE macro to get this job done(use two funtions unicode_to_utf8(), utf8_to_unicode()). Sorry for not helping.

[Joel Bodenmann]

Not sure what you are talking about. _LFN_UNICODE is a macro that is only used by the FatFS library, it has nothing to do with µGFX text rendering at all.

~ Tectu

[jayjiang]

if _LFN_UNICODE marco is disabled, fatfs libary will convert the LFN from unicode to codepage(eg. 936 or ascii). Codepage could not directly convert to utf8 and need convert back to unicode first. I hope you understand what I am saying because my english grammar is poor.

[mobyfab]

Hey,

I don't think you need UTF-16 to make it work if you fix the offset table size limit.

However in case of languages not using the latin alphabet (or very little of it), it would be more efficient as most characters will need 3 bytes in UTF-8, and only 2 in UTF-16.

[inmarket]

While encoding as UTF8 requires more storage than UTF16 for chinese, UTF-16 requires a whole new set of string handling functions which means that unless you have lots and lots of text any gains from moving to UTF-16 is lost in the extra code required.

Never the less, I have just finished another little side project (re-invigorating the Arduino port of ugfx) so I will work on this next.

The first problem to be solved is the offset table produced by the mcufont encoder (and its corresponding ugfx decoding code).

Once that is done I will look at adding UTF-16 support and if it is simple enough I will add that too.

Expect the process to take a week or so.

[jayjiang]

you can just find the problem in "compute_char_ranges()" function.

[jayjiang]

Hey,

I don't think you need UTF-16 to make it work if you fix the offset table size limit.

However in case of languages not using the latin alphabet (or very little of it), it would be more efficient as most characters will need 3 bytes in UTF-8, and only 2 in UTF-16.

yes, for now I use a function to convert utf16 to utf8 and then display it. it works fine.

[inmarket]

Can you please attach (in a zip file) your font that causes the offset table problem. Please also provide the mcufont encoder command line flags you used.

This will just make the debugging easier.

Thanks.

[jayjiang]

mcufont_encoder.exe import_ttf simfang.ttf 16 bw

mcufont_encoder.exe rlefont_export simfang16bw.dat

simfang.zip

[inmarket]

Sorry for the long delay, we have been very busy.

The mcufont encoder is now fixed in the ugfx repository but for the source code only. We have not rebuilt the binaries yet or updated the online version. We will do that over the next few days.

[inmarket]

The binaries in the repository have now been updated.

Tectu will update the online converter in the next few days.

[Joel Bodenmann]

We updated the online font converted. Can you please give it a try and let us know whether everything works now?

~ Tectu

[Asaliii]

I am trying to convert .otf format of my font using your linux mcufont converter. I am also missing some characters in different font sizes. Does anyone know what is this about?

I am filtering my font so it won't be too big. 

I am missing some characters in size 14, but when I change my size to 16 it shows it correctly. but there is also a character that I can't show it in either sizes. 

Is that because I am using otf format and my command in import_ttf ?  I didn't find any other solution to create my .c files.

[inmarket]

Try using a online font converter to convert from otf to ttf. Google will help you find one.

The uGFX font converter may or may not work with otf files - I either case it is not on the official support list.