Composites of Composites - Good or Not?

Bhikkhu Pesala · Post by **Bhikkhu Pesala** » Wed Dec 01, 2004 2:58 pm

If I want to add a dot accent below to a font that already has dot accent above, is it OK to use a composite for that and just shift it down, then use that composite dot accent below as an element in other composites?

It seems to work just fine, but is it good practice?

A similar dilemma is how to compose stacking accents like A ring acute. Is it better to make A + ring + acute, or A ring + acute?

Erwin Denissen · Post by **Erwin Denissen** » Wed Dec 01, 2004 3:57 pm

As far as I know there are no specific guidelines about the use of composites in composites. You should use them as you like. You could of course look at other fonts.

Bhikkhu Pesala · Post by **Bhikkhu Pesala** » Wed Dec 01, 2004 9:38 pm

That seems to work well. I created combining diacritics from spacing modifier diacritics, and inverted breve and caron, from breve and caron.

Using composites of composites meant that inverted breve and caron below could be scaled vertically by 90% to fit better. One cannot rotate (invert) and scale glyphs at the same time, but one can scale a glyph that has previously been inverted.

Erwin Denissen · Post by **Erwin Denissen** » Wed Dec 01, 2004 10:31 pm

Note that the behaviour of the 'Use this glyphs metrics' operation is undefined for rotated composite components.

Another thing I read here is this:

3.2.1 The composite instruction SOFFSET for performing flipping, scaling or other transforms should not be used.

This only applies to composite glyphs that have instructions (hinting). So it might be wise to stay away from both Scale and Rotation on the Common Glyph Properties window.