El Dimarts, 8 de maig de 2012, a les 14:45:25, suzuki toshiya va escriure: > Hi,
Hi, > Recently I was working with a bug #47333 > https://bugs.freedesktop.org/show_bug.cgi?id=47333 > that non-square glyphs are not laid out correctly in vertical > writing mode. The font dictionary of PDF may have the width(s) > of the glyphs for horizontal/vertical writing mode, as DW, W > and DW2, W2 key-value pairs. If these key-value pairs are not > explicitly written in the PDF, current poppler uses the default > values defined in PDF spec. The values written in the embedded > font file stream are not used. > > Reading PDF specs carefully, it was written that the values > defined by DW, W, DW2, W2 should be consistent with the metrics > in the embedded font file stream. And, it seems that Adobe Reader > (and Ghostscript) uses the metric values written in the embedded > font file stream, if DW, W, DW2, W2 are not explicitly defined. > > So I guess poppler is expected to deal with the metric values > written in the embedded font file stream. What tools we have now? > We have FoFi (thin, and light-weight) or FreeType2 (rich, slower- > than FoFi, and sometimes missing). > > At present, FoFi does not seem to be able retrieve the metric > values from embedded font file stream. In the case of bug#47333, we > have to retrieve the metric info from embedded Type1. To do > such, we have to parse the CharStrings for each glyphs, and > obtain the metric info. Fortunately, PostScript Type1 CharStrings > request that the metric info must be written at the beginning > of the glyph program for each glyphs. Thus, we don't have to > use a whole interpreter of PostScript Type1 or Type2 CharStrings > (ah, yet I've not checked the situation in Type3 font). > > So, it might be possible for FoFi to have a feature to retrieve > the metric info from the embedded font file stream. But is it > the way to go? Using FreeType2 is easier & safer? I think it > is related with the situation "when we make a poppler WITHOUT > FreeType2?". Personally i'd like it into FoFi unless it's a huge amount of work. > BTW, this issue is not 0.19.x-specific. It would be long running > issue and shared with XPDF. If I should discuss with XPDF authors, > I will do so. Please comment! That's up to you, XPDF is a totally separate project, if you are interesting in discussing with them it's you that have to decide that, not us. Cheers, Albert > > Regards, > mpsuzuki > _______________________________________________ > poppler mailing list > [email protected] > http://lists.freedesktop.org/mailman/listinfo/poppler _______________________________________________ poppler mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/poppler
