How to combine glyphs together?

[viceroy]

Here is my question with courtesy from Daniel.
Is there anyway to overlay character contour on top of background gridline contour so as to make a new one?
For example, I want to cover Letter “D” with some horizontal lines.

Thank you and best regards,


Daniel
Nov 15, 2003

[Joop_Jagers]

Yes, just copy a horizontal line from another glyph and paste it on top of the D. But please note that intersecting contours are non compliant with True Type specifications. That’s why they are reported as errors by Font Creator. This doesn’t mean that this kind of glyphs don’t work properly. They do in most programs, but there’s no guarantee the work in all programs.

[Yehuda]

But please note that intersecting contours are non compliant with True Type specifications.

I’ve been wondering about this. Is this true only for simple glyphs (for which it may make sense) or also for composite glyphs (for which it seems to make no sense)? FCP flags both.

[Joop_Jagers]

As far as I know this is true for both simple and composite glyphs, which is why FC flags both of them. You’ll notice in professionally made fonts that glyphs with overlapping components (like c cedilla), which could be made quite simply in a composite glyph, are in fact simple glyphs without intersecting contours.

[Jowaco]

If what you say is true, and I certainly have no reason to doubt it, then Microsoft:

(a) Do not provide ‘professional’ fonts
(b) Pay no heed to True Type specifications

Ccedilla in my version of Arial, supplied with Windows Me, is clearly a composite and clearly shows overlapping contours.

Joe.

[ErwinDenissen]

A similar question was asked in the topica OpenType list.

Here is part of a topic that was posted on the OpenType list at:
http://www.topica.com/lists/opentype/read/message.html?mid=1714725949&sort=d&start=3273

You have to be a member to read this email discussion group, so here are some quotes:

[quote=“Thomas W. Phinney
Fonts Program Manager
Adobe Systems”]
Although it is not a requirement of the OpenType specification, both Microsoft and Adobe consider it a bug in their own fonts if there are overlapping paths. On our part, we don’t consider it a huge bug, but still a bug. Instead the two components should be merged into one outline.

The reason it’s a bug is that there are a variety of situations in which the character might get stroked or outlined, in which case the overlap would cause problems.
[/quote]

Here is the response from Vincent Connare (designed and produced Comic Sans and Trebuchet):

@Vincent Connare

When I was at Microsoft overlapping contours were not considered a bug or wrong. It was a problem with older devices. If you want to avoid the problem on old devices or ones that render them poorly you should not use overlapping contours. If these devices aren’t a concern, a composite character is easier to create and maintain the shape and hints of the base glyphs.

In the current Font Validator it is only a ‘warning’ and you can find some of the fonts that are shipped by Microsoft have overlapping contours.

I guess you won’t find any overlapping contours within fonts created by Microsoft in the next generation of Windows (Longhorn). Longhorn is expected to be released in 2005 or 2006, so we have to be patient…

[Joop_Jagers]

No doubt you’re right. Microsoft’s most recent font, Tahoma of XP Service Pack #1, still has a number of glyphs with intersecting contours, but far less than Arial.