widelands-dev team mailing list archive

[Holger Rapp <HolgerRapp@xxxxxxx>]

Aaah, I was expecting this discussion to come up :). So here is my line of reasoning for DejaVu:

FreeSerif and FreeSans (the new versions) looked strange when used with ptsize < 14. The characters were jumping up and down in a single line. Granted, I did not invest much time to bug fix this issue. I could see that this is a bug in our ascent calculation (the old font renderer which is still in use in most places ignores the ascent informations from the font files as they are wrong in the fonts we currently ship). But I found other people in the internet having the same trouble with free*.ttf, so I decided to instead switch to DejaVu. 

> 
> Some years ago Widelands delivered fonts, which licenses were incompatible to the GPL. Because of that we had a discussion on our mailing list and finally I took the task to search for a replacement for those fonts. In general there were three points I had to think about: 
> * the license of the font
> * how many supported glyphs it has (does it provide glyphs for arabic, japanese, etc.? - if we have translations, they should be useable in game - there is still a problem with languages with right to left text, but that's another topic)
> * and of course the style of the font
> 
> So coming back to todays situation: SirVer merged an awesome new text render system two days ago :). Following this merge, he is now improving the texts in game and did replace the FreeSerif font with the DejaVu fonts. As far as I understand his commit messages, his point is about "style" - the look of the font. But I fear it's not that easy.
> 
> Let's compare the fonts for the three points mentioned above:
> 
> 1. The FreeSerif and FreeSans fonts from the freefont project at http://savannah.gnu.org/projects/freefont/ ae the ones we used in the last years. However the ones we deliver are an already quite old release and it seems SirVer did not like their look ;). Positive side is: the ones we deliver are still licensed GPL v2.
DejaVu ships with Wesnoth and we do not have to show the license to the end user, we just need to ship it with the font files (done already in trunk), so from a legal point of view we are save and can still release under GPL (wesnoth does the exact same thing and have been doing for years, AFAIK not even the debian people have been grabbing their pitchforks yet). Of course this is my interpretation and I am not a lawyer.

> 2. The current release version of the FreeSerif and FreeSans fonts are even more complete than the ones we currently deliver. As far as I found out in the internet, it is still by far the most complete GPL compatible font. This means, no other font can provide us with support for that many different glyphs (and thus languages). Further it's look was improved. Negative side: it is now licensed GPLv3 or higher - to use them in a Widelands software bundle (e.g. installer for Windows), we would have to license the whole bundle and so Widelands GPLv3 as well or show different licenses for different parts of the bundle.
DejaVu has a lot of glyphs and as it stands now, Widelands can not handle left to right or top to bottom rendering. So you can basically not play it with non-latin fonts anyway. 

> 
> 3. The DejaVu fonts that SirVer included in Widelands because of their style are released under a free license (Bitstream Vera Font Copyright and Arev Font Copyright - http://dejavu-fonts.org/wiki/License). However all discussions on the internet I found in a 5 minutes search only pointed out, that those fonts are used in open source projects (under GPL) and thus seem to be GPL compatible ;) ... Following those dicussions I guess we are save to use it, but to be strict, it's license is not GPL, so if we include the DejaVu fonts in a software bundle, we would have to show the GPL as well as the DejaVu license.
As mentioned, I do not think this is true. You only have to bundle the license with the fonts (in the same directory I think.

> BIG NEGATIVE point of DejaVu fonts is the number of glyphs they provide. They only provide Latin, Greek, Cyrilic, Armenian and Georgian Glyphs (see     http://dejavu-fonts.org/wiki/Main_Page), some more glyph sets are incomplete, like arabic, some are not at all provided like japanese, chinese, etc.
As mentioned, I do not see this as a real problem. Having a quick look at the current translation status on launchpad shows that the only critical languages might be greek and russian. My understanding is that DejaVu has glyphs for this languages though my limited knowledge of the languages does not allow me to check. Chinese is well below 10% translated and arabic is even below. So I do not see such a big problem here.

> 
> I see different possibilitys to handle this:
> 
> 1. Go by one font that provides glyphs for almost all languages, so a "select used font option" is not needed. the freefont project fonts are not 100% complete (concering the unicode standard), but by far more complete than the DejaVu fonts, so if we take this way, they would be our choice.
I am not emotionally attached to DejaVu. The new text renderer does use "proper" fonts for bold and italic though, so whatever font we ship, we must also include "*Bold.ttf", "*BoldItalic.ttf" "*Italic.ttf", this is really the only requirement I have. If someone figures out the layouting problems with the new Free* fonts, I can totally live with them.

> 
> 2. Widelands already supports an option to select a font for the main menu - if that option is improved to be usable for the whole game, it could be used for selecting a "font set", that defines different fonts and styles (heading, buttons, texts, etc.). That way we could use different fonts and users could change the font for the whole game, if their glyph set is not supported. This could maybe be improved that far, that cmake includes an automated script that searches for fonts it knows and generates new font sets. (To explain the idea behind that option: If you install libreoffice on Mageia linux and select to install the japanese translation for libreoffice, the needed fonts are installed as well. If japanese is not installed, the fonts are not needed as well…)
The problem here is that a lot of layouting in Widelands is done by assuming pixel sizes, so switching out a font breaks a lot of layouts throughout the game. So while I believe it would be good to make the fonts replacable on a per language basis, I would not allow the user to do so, but do it on a per language level (so we could use another font for chinese glyphs for example) and keep the number of supported fonts low and ship them with the game.

> My question: what do you think is the way to go?
> 
> Personally I prefare to go with option 1 (only one font set) for now and update the freefonts to their new version. This opinion is simply based on the idea, that option 2 might be quite a lot of work and would only be usable, if right to left text is usable in Widelands as well.
I believe right to left text is very far off as is top to bottom. I invested a lot of time in investigating the current possibility (pango and harfbuzz mainly) for better text layouting and they all where let downs. The new text renderer could be adapted to work for left to right rather easily if text rendering where available. Top to bottom is nearly impossible to achieve as horizontal layouts are everywhere in Widelands. So from my point of view, I prefer the solutions in the following order:
1) stick with DejaVu and calling things done until someone complains convincingly that this choice makes it impossible to play Widelands in his language now though it was possible before. I think it unlikely that this ever happens.
2) roll back my commits and keep using Free* fonts. Someone (not me) would need to figure out how to fix the weird rendering and I would want more choices in the font styles (for example having a condensed form for the numbers in warelists  displays makes the menu nicer to look at).

Cheers,
Holger