Wed 12 Mar 2008 11:29:55 PM UTC, comment #4:
Finally have a handle on this.
No longer sure if it should properly be called "anti-aliasing" or "TrueType hinting".
In Windows Vista, can switch between "ClearType" and "Standard" antialiasing.
Control Panel -> Personalization
-> Window Color and Appearance
-> Effects
They are quite different, neither seems as good as the X-Windows analog, and...they don't fix the problem, only blur it.
By a process of elimination, I found the thing that produced pretty good results in Serif was TrueType tables left over from some previous experiment.
1) TTF fonts look better at smaller sizes if and only if their FontForge
.sfd file contains TrueType hinting tables. These look like
ShortTable: maxp 16
EndShort
TtTable: prep
...
EndTTInstrs
TtTable: fpgm
...
EndTTInstrs
ShortTable: cvt 7
EndShort
2) These don't appear to be connected to anything in the FontForge GUI when editing a font with cubic splines.
3) If the splines are changed to quadratic (Font Info -> Layers ) however, the menu items Hints -> AutoInst, etc are enabled. These seem to use existing hints and PS Blues values to produce TrueType hinting instructions.
4) The TrueType tables aren't deleted if the splines are changed back to cubic. (But they surely lose any connection to any later changes made to glyphs.)
5) To AutoInst, requires glyphs to be TrueType conformant already, so can't have mixed contours and references in one glyph, for example. (Also saw problems when Validate turned up poor Blues values.)
6) How badly does two transformations of spline order screw up glyphs? Don't know. But it isn't a perfect transformation. Just going one way always causes trouble.
7) Can the tables be simply copied from a cubic version to a quadratic? Yes.
8) Of course this could all be avoided by just switching to OpenType, but some important apps still don't support that.
So for now: I'm making quadratic spline versions of each font, copying the TrueType tables by hand to the cubic spline versions, and saving it. It's a hack.
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