Ah, Bevan's proposal is reasonable... I selected 3 Type42-required subtables (cvt/fpgm/prep) which are very difficult to subset without detailed interpretation of glyf program. So, even if the embedded fonts are subsetted, usually they are same with original fonts.
# If they are modified, it means that the embedder should # have some TrueType instruction interpreter, so I want # the embedder to care about the hinting. And, FT2 has builtin checksum calculater. In fact, some PDF generators don't write the checksum at all (maybe they don't want spend CPU cycles to recalculate checksums for subsetted tables like loca, glyf, etc), in such case, FT2 calculate the checksum by itself. When I designed so, I was thinking that most TrueType embedders may calculate the checksum correctly, or copy the checksum, or leave the checksum as 0x00000000, so, skipping the checksum recalculation for non-zero value makes the tricky font checking faster. In fact, now, the trickyness check by the checksum is executed for most non-tricky TrueType fonts (it's ironic!) Anyway, my assumption might be wrong. I should check the cost of checksum recalculation by some benchmarks... Regards, mpsuzuki On Thu, 28 Apr 2011 11:43:13 +0200 (CEST) Werner LEMBERG <[email protected]> wrote: > >> For some reason I assumed that FreeType would be calculating the >> checksum. I'm sure there's lots of code that doesn't bother to set >> the checksums at all. > >The problem are subsetted fonts, I believe. > > > Werner _______________________________________________ Freetype-devel mailing list [email protected] https://lists.nongnu.org/mailman/listinfo/freetype-devel
