"middle" does not refer to the base line of the font

I hope you meant "use the overall font metrics to middle-align the text" and not "make middle the same as lower"

Or better, just use the letter 'M' to determine middle alignment.

KaiMartin: Could you please check whether the alignment of text is correct in the PS output, or whether it exhibits the same behaviour?

DJ:

> Or better, just use the letter 'M' to determine middle alignment.

How is that "better"? That heuristic depends on the invalid assumption that the text uses the Latin alphabet.

Using the overall font metrics is the "right thing" here, but as usual we need to be careful not to gratuitously break everyone's existing schematics.

The reason "M" is better is because overall font metrics include EVERY glyph, even ones that extend an unusual amount outside the "norm" for the font. I suppose you could use "font size" to come up with something relative to the baseline, but that will require some tweaking to get results that look good across a variety of fonts.

Also, "M" is most like what "everyone's existing schematics" is already using, and is a decent representative of "average glyph size" even if the "M" (or other iso-latin-1 glyphs) doesn't occur anywhere in the string.

@ DJ: Yes, I meant, the marker should correspond to the middle of the font. This might be calculated as the mean height of all glyphs. If the height of base line and mid line are available, these may be used to calculate some reasonable approximation to the mean height.
The vertical shift should depend on the font, not on the actual string.

@Peter Brett: Postscript output shows the same symptoms. See attachment.

---<)kaimartin(>---

Okay, this is clearly something we need to think about fixing. Since the print output and on-screen appearance are at least consistent with each other at the moment, it's not particularly urgent IMHO.

I think it's reasonable to say that we should aim to keep the appearance of the reference card (gschem/examples/drawing_primitives.sch) the same when we fix this.