Font Charis SIL with kerning and respaced italics

IceHand · 02-20-2015, 02:19 PM

The original Charis SIL does not include any kerning information and the italics are spaced rather tight (e.g. look at "gr" – they are touching and imho they shouldn't).

Since Charis is based on Bitstream's Charter I took it upon myself to copy the kerning information from Charter to Charis (I don't know why they didn't do that in the first place). Some kerning pairs were missing that I added (e.g. "Tä", "Wé" etc.). I also respaced the italics based on Charter's spacing.

Charis' license requires that modified versions of the font do not include "Charis" and "SIL" in its name, so I simply renamed the font to "Charta" (German for "Charter"). I made these changes a few years back for some print projects so the font is based on Charis 4.110.

Oh, and my version of the font only includes the basic latin subset of characters to make my life easier while modifying the font and I had no need for more characters.

Feel free to make modifications of my version. I can also include Fontforge source SFDs if needed.

Note: Most e-readers do not support kerning or only very basic kerning that's mostly useless (e.g. Cool Reader). I only know of FBReader that offers good kerning support. And yes, I hate that dedicated reading devices do not include support for something as typographically fundamental as kerning.

Edit: As GeoffR pointed out, kerning and thus this font works well with Kobo's epub reader (but not with Kobo's kepub reader, see below).

ymmv · 02-23-2015, 08:15 AM

What a great idea! I've used this font for a number of custom ebooks but it can look really awful at different font sizes.

One thing though: only the basic Latin set? A-Z and a-z plus the most common punctuation marks? This means that your font won't handle words like fiancée, señor, Übermensch, ménage à trois, Beyoncé, façade, fin de siècle, etc. You'd be surprised how often English words with diacritics crop up in books.

IceHand · 02-23-2015, 02:03 PM

Sorry, "basic latin subset" was a bit misleading. Your examples will display just fine. The original Charis SIL includes Greek, Cyrillic and stuff like that – this I did not include. See the attached image for all included characters.

JSWolf · 02-23-2015, 02:06 PM

Did you also add hinting? Charis SIL does not have hinting. Also, all the characters you've deleted should be put back in. Making the font a shell of itself is a rather bad idea.

IceHand · 02-23-2015, 02:42 PM

No, I did not. Feel free to modify the font, if you want to. It works perfectly for my purposes so I see no need to modify it further.

MacEachaidh · 02-24-2015, 01:18 PM

Quote:

Originally Posted by JSWolf

Did you also add hinting? Charis SIL does not have hinting. Also, all the characters you've deleted should be put back in. Making the font a shell of itself is a rather bad idea.

Does the Kobo (f'rinstance, since that's what I use) recognise hinting, though? (Genuine question; not arguing, asking.) If not, then there's no point in swelling the size of the font with typographic features that won't be employed.

GERGE · 02-24-2015, 01:24 PM

Rendering engine in Kobo supports kerning and hinting.

IceHand · 02-24-2015, 02:02 PM

Quote:

Originally Posted by GERGE

Rendering engine in Kobo supports kerning and hinting.

Are you sure about kerning? All images I've seen of Kobo readers did not show proper kerning. Could you maybe make a photo with typical kerning pairs like "Wa", "Vo" or "Yo"?

MacEachaidh · 02-24-2015, 02:03 PM

Merhaba Gerge, and thanks. ;-)

One reason for my asking is that I've been formatting an ePub using Gentium Book (another SIL typeface) as the main body font; it looks fine on my Aura HD (3.12.1) at various sizes, but on my Kobo Touch (3.11.0) the Italic variant looks horribly mangled at any size I've tried. No doubt a major contributor to this is the pixel density of the screen (168 vs 265), but the same font renders fine in any of my desktop apps at normal PC screen resolution -- hence my questioning of hinting.

If anyone has any suggestions on resolving this -- or even suggestions of a similar typeface that renders better on a Touch or Glow level of display -- then I'd be grateful to hear of them.

JSWolf · 02-24-2015, 09:22 PM

I've tried this font and I've fount you've removed too many characters that are actually used. What's needed at least is the full Latin, bit just a basic subset.

GeoffR · 02-25-2015, 01:54 AM

Quote:

Originally Posted by IceHand

Are you sure about kerning? All images I've seen of Kobo readers did not show proper kerning. Could you maybe make a photo with typical kerning pairs like "Wa", "Vo" or "Yo"?

Kobo devices come with two different readers, one used for Kobo's kepub format, and the other based on RMSDK used for epubs. Users can choose which reader they use for sideloaded books. The epub reader appears to support kerning, but the kepub one doesn't.

Here are screenshots from my Kobo Glo (firmware 3.13.1) with the Charta font downloded from this thread. The first is in the epub reader, the second in the kepub reader:

IceHand · 02-25-2015, 07:07 AM

Quote:

Originally Posted by JSWolf

I've tried this font and I've fount you've removed too many characters that are actually used. What's needed at least is the full Latin, bit just a basic subset.

Just to be clear: My font includes more characters than Bitstream's Charter Postscript Type 1 font, on which Charis SIL is based. So ISO-8859-1 at the very least is covered. If you really need more, I might release a version with all characters from Charis. But kerning won't be available for those extra characters and it won't work for the italic version, because I've respaced it completely.

IceHand · 02-25-2015, 07:10 AM

Quote:

Originally Posted by GeoffR

Here are screenshots from my Kobo Glo (firmware 3.13.1) with the Charta font downloded from this thread. The first is in the epub reader, the second in the kepub reader:

Nice, thank you! Kerning looks good with the epub reader. Also, comparing those two images you really see the difference between kerning and no kerning.

Does the Kobo support hyphenation too? I might just buy a Kobo if the epub readers works well.

GeoffR · 02-25-2015, 07:31 AM

Quote:

Originally Posted by IceHand

Nice, thank you! Kerning looks good with the epub reader. Also, comparing those two images you really see the difference between kerning and no kerning.

After a bit more testing, it seems the kepub reader does support kerning, but only for TTF fonts (assuming the font contains kerning data, which the default Georgia font doesn't). The epub reader supports kerning with both TTF and OTF fonts.

Quote:

Does the Kobo support hyphenation too? I might just buy a Kobo if the epub readers works well.

Both readers support automatic hyphenation, although the epub reader does a better job of it (the kepub reader seems to place the hyphen one place to the right of where it should be in some situations.) How good the automatic hyphenation is depends on the quality of the hyphenation dictionaries, the default dictionaries are quite good for English, not so good for other languages. You can install better hyphenation dictionaries if you have them though.

dickloraine · 02-25-2015, 07:32 AM

Yes, they support hyphenation. The default is very conservative, but you can change that by modifying the hyphenation files.

02-23-2015, 02:03 PM	#3
IceHand Linux User Posts: 323 Karma: 13682 Join Date: Aug 2007 Location: Germany Device: Kindle 3	Sorry, "basic latin subset" was a bit misleading. Your examples will display just fine. The original Charis SIL includes Greek, Cyrillic and stuff like that – this I did not include. See the attached image for all included characters. Attached Thumbnails

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02-23-2015, 08:15 AM	#2
ymmv Enthusiast Posts: 29 Karma: 24736 Join Date: Aug 2013 Device: Sony PRS-T1	What a great idea! I've used this font for a number of custom ebooks but it can look really awful at different font sizes. One thing though: only the basic Latin set? A-Z and a-z plus the most common punctuation marks? This means that your font won't handle words like fiancée, señor, Übermensch, ménage à trois, Beyoncé, façade, fin de siècle, etc. You'd be surprised how often English words with diacritics crop up in books.

02-23-2015, 02:06 PM	#4
JSWolf Resident Curmudgeon Posts: 79,591 Karma: 145863177 Join Date: Nov 2006 Location: Roslindale, Massachusetts Device: Kobo Libra 2, Kobo Aura H2O, PRS-650, PRS-T1, nook STR, PW3	Did you also add hinting? Charis SIL does not have hinting. Also, all the characters you've deleted should be put back in. Making the font a shell of itself is a rather bad idea.

02-23-2015, 02:42 PM	#5
IceHand Linux User Posts: 323 Karma: 13682 Join Date: Aug 2007 Location: Germany Device: Kindle 3	No, I did not. Feel free to modify the font, if you want to. It works perfectly for my purposes so I see no need to modify it further.

02-24-2015, 01:24 PM	#7
GERGE Guru Posts: 733 Karma: 5797160 Join Date: Jun 2010 Location: Istanbul Device: Kobo Libra	Rendering engine in Kobo supports kerning and hinting.

02-24-2015, 02:03 PM	#9
MacEachaidh Browser Posts: 745 Karma: 578294 Join Date: Apr 2010 Location: Australia Device: Kobo Touch, Kobo Aura HD	Merhaba Gerge, and thanks. ;-) One reason for my asking is that I've been formatting an ePub using Gentium Book (another SIL typeface) as the main body font; it looks fine on my Aura HD (3.12.1) at various sizes, but on my Kobo Touch (3.11.0) the Italic variant looks horribly mangled at any size I've tried. No doubt a major contributor to this is the pixel density of the screen (168 vs 265), but the same font renders fine in any of my desktop apps at normal PC screen resolution -- hence my questioning of hinting. If anyone has any suggestions on resolving this -- or even suggestions of a similar typeface that renders better on a Touch or Glow level of display -- then I'd be grateful to hear of them.

02-24-2015, 09:22 PM	#10
JSWolf Resident Curmudgeon Posts: 79,591 Karma: 145863177 Join Date: Nov 2006 Location: Roslindale, Massachusetts Device: Kobo Libra 2, Kobo Aura H2O, PRS-650, PRS-T1, nook STR, PW3	I've tried this font and I've fount you've removed too many characters that are actually used. What's needed at least is the full Latin, bit just a basic subset.

02-25-2015, 07:32 AM	#15
dickloraine Guru Posts: 631 Karma: 7544528 Join Date: Apr 2013 Location: Berlin Device: PRS 350, Kobo Aura	Yes, they support hyphenation. The default is very conservative, but you can change that by modifying the hyphenation files.

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