I guess my version has PIXEL_BITS = 6. Sorry, didn't notice the discrepancy. Yes, FT_MAX_CURVE_DEVIATIO ought to be defined so that it's always 1/4 of a pixel.
Graham ----- Original Message ---- From: Алексей Подтележников <apodt...@gmail.com> To: GRAHAM ASHER <graham.as...@btinternet.com> Cc: freetype-devel <freetype-devel@nongnu.org> Sent: Wednesday, 13 October, 2010 13:14:42 Subject: Re: [ft-devel] FT_MAX_CURVE_DEVIATION vs ONE_PIXEL Please confirm that ONE_PIXEL defined as 256 is not the unit of one pixel. What is ONE_PIXEL then? 2010/10/13 GRAHAM ASHER <graham.as...@btinternet.com>: > Alexei, > > I don't have much time or energy for this at the moment - sorry. Of course I > will be looking at it again, but I believe that the solution hammered out by > David Bevan and myself is a good one - it solves the bug I introduced while > retaining the speed increases I first made the changes for. > > Please note that the definition of FT_MAX_CURVE_DEVIATION as 16 gives a value >of > 1/4, not 1/16 as you suggest. This code works in units of 1/64 of a pixel. > > Best regards, > > Graham > > > > ----- Original Message ---- > From: Алексей Подтележников <apodt...@gmail.com> > To: freetype-devel <freetype-devel@nongnu.org> > Sent: Wednesday, 13 October, 2010 2:25:40 > Subject: [ft-devel] FT_MAX_CURVE_DEVIATION vs ONE_PIXEL > > Guys, > > Currently smooth/ftgrays.c contains this: > > /* The maximum distance of a curve from the chord, in 64ths of a pixel; */ > /* used when flattening curves. */ > #define FT_MAX_CURVE_DEVIATION 16 > > and this: > > /* must be at least 6 bits! */ > #define PIXEL_BITS 8 > > #define ONE_PIXEL ( 1L << PIXEL_BITS ) > > Wouldn't that make sense to reconcile the two and > possibly just use an explicit fraction of ONE_PIXEL instead? > If I am not confused FT_MAX_CURVE_DEVIATION could be replaced > with a larger value. 16 / 256th is really very conservative and > you still make too many splits. > > Also, s and s_limit actually mean some sort of an area measure. > It would make perfect sense to use TArea as type of these variables. > > Finally, I have more "geometrical" suggestions, but I'll wait with the patch, > until I hear back Re this and my previous message. > > > Best, > Alexei > > _______________________________________________ > Freetype-devel mailing list > Freetype-devel@nongnu.org > http://lists.nongnu.org/mailman/listinfo/freetype-devel > > -- Alexei A. Podtelezhnikov, PhD _______________________________________________ Freetype-devel mailing list Freetype-devel@nongnu.org http://lists.nongnu.org/mailman/listinfo/freetype-devel
