[softwarelist] Re: Leading calculation for lines of differing sizes

  • From: David Pilling <flist@xxxxxxxxxxxxxxxxxxx>
  • To: davidpilling@xxxxxxxxxxxxx
  • Date: Tue, 23 Jan 2007 14:02:53 +0000

In message <005301c73e8c$6258d180$9601a8c0@PC01>, John Grogan <johngrogan@xxxxxxxxxxxx> writes

Yes - I see now that it was my concept of "baseline" that was erroneous. I thought you were referring to the bottom of the text but it is in fact the line on which the body of the text sits in the conventional handwriting sense with the

Yes sorry if that was not obvious.

I recall that when I set out to write Ovation in 1988, I looked in a book on fonts, and it said "12 point text measures 12 points from the top of the highest ascender to the bottom of the lowest descender" from the top of "A" to the bottom of "g" if you like.

It then came as a painful surprise to discover that this was not true.

One of the key parameters when painting a font (at least on RISC OS) is the height of the font above the baseline.

font_stringbbox() given all characters from ASCII 33 to 255 and scaled for text

Aye and there is another story. Do you cover just codes 32 to 126 or 32 to 255? If I had to guess I'd say that OP has always used 32 to 255 for leading and Impression used 32 to 126. The codes above 127 tend to have taller characters.

There is an option on text frames to set how far down the first line of text is, depending on this range.



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David Pilling
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