Can you file a bug with reference to these details please? behdad On 09/03/10 03:50, mpsuzuki@xxxxxxxxxxxxxxxxx wrote: > On Thu, 02 Sep 2010 16:44:35 -0400 > Behdad Esfahbod <behdad@xxxxxxxxxx> wrote: >> Can you explain more why the PANOSE values are needed? And, do we need to >> allow users to query based on them, or just having them in the cache? > > In some popular document formats, like PDF, SVG, ODF and OOXML, > Panose values are embedded to give the hint for font substitution. > ================================================================== > PDF > --- > PDF Reference 6th edition (for PDF version 1.7) > 5.7.2 Font Descriptors for CIDFonts > > see the description for "Style" entry which > includes 2 bytes from OS/2.sFamilyClass, > 10 bytes from OS/2.Panose. > > SVG > --- > http://www.w3.org/TR/2003/REC-SVG11-20030114/fonts.html > 20.8.3 The `font-face' element > > there are many elements inherited from CSS2, > including Panose. > > ODF > --- > http://docs.oasis-open.org/office/v1.1/OS/OpenDocument-v1.1.pdf > 14.6.1 CSS2/SVG Font Descriptors > > ODF adopted the elements for the fonts from > CSS2 and SVG, so even the font is for the text > (not for embedded scalable graphics), it may > have Panose value in the svg:panose-1 attribute. > > OOXML > ----- > ISO/IEC 29500-1:2008 > 17.8.3.13 panose1 (Panose-1 Typeface Classification Number) > > OOXML have several font properties (GDI parameters, > Panose, and supported unicode range). In 17.8.2 Font > Substitution, there is a list of properties to be > used in the font substitution, and panose is described > as the highest priority. > > PCL > --- > "PCL 5e Technical Quick Reference Guide" > http://h20000.www2.hp.com/bc/docs/support/SupportManual/bpl13205/bpl13205.pdf > "PCL5 Comparison Guide" > http://h20000.www2.hp.com/bc/docs/support/SupportManual/bpl13206/bpl13206.pdf > > PCL5 selects the font by giving Panose parameters > sequentially and narrowing down the candidates, > see PCL 5e Technical Quick Reference Guide p 11-15. > > See table 1-1 "PCL5 Feature Support Matrix" in > page 1-12 PCL5 Comparison Guide, many PCL5 > implementations support the feature to narrow > down by Panose parameters. > > Also PCL6 (PCL XL) supports the feature by > giving a string of PCL5 commands to PCLSelectFont > attribute. > ================================================================== > In addition, current fontconfig does not have easy element to > be related with CSS's 5 family classification (serif, sans- > serif, cursive, fantasy). I think getting FamilyClass & Panose > values from fontconfig cache may be helpful, because the > application don't have to open a face, load OS/2 table, > check FamilyClass/Panose values, close a face. > > The font selection by the matching of familynames & charsets > leaves a room for an improvement, because severeal documents > formats (and CSS) have these properties in the documents. > > -- > > The query based on these properties is arguable. The algorithm > to evaluate "best matching" font by Panose is not specified > in Panose specification paper. If exactly same, it is ok - but if > different, it is arguable how the similarity should be evaluated. > Some people want to give the highest priority to serif/sans-serif > contrast, others want to give it to weight similarity. At present, > I don't have good idea that everybody think it as acceptable. > > Thus, I think just giving the APIs to provide these properties > (FamilyClass, Panose, etc) is appropriate starting point. It > is still convenient for fontconfig client applications because > they can reduce the costs to open/check/close many font files > by themselves. > > # In fact, in PCL5, the priority of each bytes in Panose is user > # controllable. > > Behdad, could I answer to your question? If I'm misunderstanding > what I was requested, please give me one more chance. > > Regards, > mpsuzuki > > P.S. > If putting so many data to fontconfig is bad idea, please let me > know. > >> On 09/02/10 14:24, mpsuzuki@xxxxxxxxxxxxxxxxx wrote: >>> Hi, >>> >>> How can I store FC_MATRIX object to cache file? >>> >>> -- >>> >>> Now I'm trying to add some properties to fontconfig database, >>> which are taken from OS/2 and PCLT tables in OpenType: like >>> sFamilyClass (so-called IBM family classification), Panose etc. >>> They are useful to guess whether typeface is typographic/scriptic, >>> serif/sans-serif, proportional/fixed-pitch etc. My original >>> motivation is an improvement of the font substitution in poppler. >>> For detail, please find: >>> >>> https://bugs.freedesktop.org/show_bug.cgi?id=5168 >>> >>> Panose in OpenType is a collection of 10 parameters, and >>> all parameters are expressed by 8bit. 80bit is too large >>> to pack into double integer, so I have to consider what is >>> the best way to store such in FcPattern. I think there are >>> 3 options: >>> >>> 1) Name all parameters and store separately, aslike, >>> adding 10 types to FcObjectTypes: FC_OS2_PANOSE_0, >>> FC_OS2_PANOSE_1, ... >>> >>> # The name of each byte is different from OpenType spec >>> # and its reference, so I don't use OpenType spec name >>> # like FC_OS2_PANOSE_FAMILYTYPE. >>> >>> 2) ASCII-fy 10 parameters to NULL-terminated string, >>> and use as a string type property. >>> >>> 3) Define new data type, a structure including 10 members >>> and add "FcTypePanose" to FcType. >>> >>> -- >>> >>> About 1), it's easy for me to write such patch and for >>> users to use, but the addition of 10 objects may be too >>> much, because current variety of the object type is 41. >>> >>> About 2), it's easy for me to write such patch but tricky >>> for users to use, because it is requred to decode from >>> ASCII string to original data. >>> >>> About 3), it's easiest for users. So I have to consider >>> about this option. >>> >>> Checking the source code of fontconfig, FcMatrix data >>> type looks similar (a structure with fixed length), but >>> it seems that the data typed FcMatrix cannot be stored >>> in cache file. I inserted FcMatrix object to FcPattern >>> and tried to save it in cache file, but it seems that >>> FcMatrix typed data cannot be saved (fc-cat can read >>> object type but cannot read value). >>> >>> The code for FcString, FcCharSet and FcLangSet are >>> variable length data and have many works. So I want to >>> know how I can store FcMatrix typed data to cache file. >>> >>> Regards, >>> mpsuzuki >>> >>> P.S. >>> If option 1) or 2) are acceptable for fontconfig maintainers, >>> I will do so. >>> > _______________________________________________ Fontconfig mailing list Fontconfig@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/fontconfig
