Re: [ft-devel] New `slight' auto-hinting mode

[Alexei Podtelezhnikov]

>>> I can only repeat: Hinting and subpixel positioning *can* work
>>> together!  There is absolutely no reason why this shouldn't be
>>> possible.
>>
>> The brilliance of lsb_delta and rsb_delta method is that it
>> recognizes that two extreme edges of the glyph are hinted mostly
>> independently.  For these two degrees of freedom it uses two numbers
>> and then cleverly adjusts spacing between glyphs using these
>> numbers. I doubt the information contained in two numbers can be
>> squeezed into one fractional width. It is only possible if two
>> numbers are related rather than independent.  This is pure theory.
>
> Well, lsb_delta and rsb_delta are derived from the horizontal phantom
> points.  Given that the idea of `phantom points' is originally a
> TrueType concept, I don't see why this shouldn't work with TrueType
> hinting.

Werner,

Currently there is a need to adjust pen position when hinting places
two adjacent glyph edges too near or too far. This concept does not go
away with subpixel pen positioning. Essentially, this mean that each
glyph advance *must* depend on the previous pen position. I doubt that
this is easier to comprehend than lsb_delta and rsb_delta.

Again, the light and no-hinting modes are different because the pen
position is never adjusted there - just straight rounding,

Alexei