[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
composition text property
From: |
Drew Adams |
Subject: |
composition text property |
Date: |
Wed, 30 May 2007 09:08:38 -0700 |
>From the Elisp manual, node Special Properties, `composition':
This text property is used to display a sequence of characters as a
single glyph composed from components. For instance, in Thai a
base consonant is composed with the following combining vowel as a
single glyph. The value should be a character or a sequence
(vector, list, or string) of integers.
* If it is a character, it means to display that character
instead of the text in the region.
* If it is a string, it means to display that string's contents
instead of the text in the region.
* If it is a vector or list, the elements are characters
interleaved with internal codes specifying how to compose the
following character with the previous one.
I must be misunderstanding this - perhaps someone can explain. I try this:
(put-text-property
(point) (1+ (point))
'composition "Hi there!")
I expected to see "Hi there!" displayed in place of the character before
point ("display that strings contents instead of the text..."). Instead, I
see no visible change. `C-u C-x =' shows that the composition property was
applied. I also tried applying the property this way to several consecutive
characters (expecting to see "Hi there!" in place of each), but with no
visible change.
I also tried looking at Emacs source code that uses this property, but I
didn't find much, and what I found didn't enlighten me.
What am I missing? Thx.
BTW, should the text really be speaking of "the region" here? I tried with
and without an active region, with no visible change. I suspect that this
has nothing to do with the region, and I'd file a bug, but I don't yet
understand this text (obviously). Shouldn't "the region" be "the characters
with property `composition'"?
Also, the illustration of Thai doesn't help (me) much. How about a code
example, showing how `composition' can be used to compose a Thai consonant
and its following vowel, forming a single glyph?
[Prev in Thread] |
Current Thread |
[Next in Thread] |
- composition text property,
Drew Adams <=