Depends somewhat on the usage of the font and what rasterizers you care about. But the big question is, do you need to preserve the spacing at low ppems, or are you willing to have the spacing get looser to maintain legibility?

Most folks doing manual hinting are willing and able to distort the spacing at low ppems, which allows for the possibility of either using left-to-right hinting across the glyph, or using intermediate deltas that affect the right sidebearing to open up a glyph that is hinted outside-in.

T

I generally prefer to hint from left to right, as this makes it easier to preserve good lettershape. If you hint from the outside in, you have limited options for controlling the width of internal counters, which might get squished or extended at some sizes. You end up having to helta hint the whole character width at certain sizes, whereas if you hint from one side to the other you can specify a CVT white space value to control the counter as if it were a stem.

I tend to prefer hinting LTR, too, but you have to be willing to play hell with the sidebearings.

T

I have been using the left-to-right approach as well, but FontLabs default auto-hinting settings are for outside in and I was wondering if there is any advatage to this approach.

Thank you both for your comments.

...but you have to be willing to play hell with the sidebearings.

I'm not sure I understand this comment, Thomas. It seems to me that you can control sidebearings in the same way, i.e. with a link, regardless of whether you hint inwards or right-to-left.

Oops, I meant to say advance widths. Actually, I meant to say that earlier as well: the question is whether you need to maintain WYSIWYG (not distort the advance widths) or not.

T