Re: NSGlyph
Re: NSGlyph
- Subject: Re: NSGlyph
- From: Douglas Davidson <email@hidden>
- Date: Sat, 4 Oct 2008 12:26:28 -0700
On Oct 4, 2008, at 11:59 AM, email@hidden wrote:
I can't figure out how NSGlyph works in methods like this:
[path appendBezierPathWithGlyph:'x' inFont:[NSFont userFontOfSize:
14.0]]
(Of course 'path' is an NSBezierPath.)
What I get on the screen is not an '+', but an upper-case "H" in
some outline font. And when I put in explicit Unicodes, I don't get
the expected symbol either.
NSGlyph is declared as an unsigned int. But how is it connected to
displayed characters?
You should take a look at some of the text system conceptual
documentation, such as http://developer.apple.com/documentation/Cocoa/Conceptual/TextLayout/TextLayout.html
.
Glyph are not characters, and in general they do not have a simple
relationship to characters. A glyph is an individual displayable
element in a particular font, and its numerical value is an index into
the font's glyph repertoire; this numerical value does not in general
have meaning outside of the context of that particular font.
The Cocoa text system converts characters into glyphs as needed for
text display; in general, NSLayoutManager manages this process, with
the help of two auxiliary classes, NSGlyphGenerator and NSTypesetter.
The first of these performs a first-pass conversion of characters to
glyphs, while the second makes any contextual adjustments that are
necessary as the text is laid out. The final mapping between glyphs
and characters need not be one-to-one; for example, even with Latin-
script text, in many fonts the two characters "fi" will be represented
by a single "fi" ligature glyph. Other scripts, or specialized fonts,
can produce much more complicated character-glyph mappings.
Try taking a look at the "SpeedometerView" example on
developer.apple.com. It includes among other things a mechanism for
producing bezier paths from arbitrary text, in the SpeedyCategories.m
file.
Douglas Davidson
_______________________________________________
Cocoa-dev mailing list (email@hidden)
Please do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden
| References: | |
| | >NSGlyph (From: email@hidden) |