Re: redisplay system of emacs

[Lennart Borgman]

On Thu, Jan 28, 2010 at 1:43 PM, Eli Zaretskii <address@hidden> wrote:
>> From: Lennart Borgman <address@hidden>
>> Date: Thu, 28 Jan 2010 12:47:26 +0100
>> Cc: address@hidden, address@hidden
>>
>> The Mozilla display engine displays images and text with different
>> properties very well. And it is very flexible in its way to do that
>> (since CSS requires that).
>
> Even images support in Emacs (which is admittedly young and unevolved)
> already supports advanced features like :pointer and :map (see the
> node "Image Descriptors").


?? Of course Mozilla supports these kind of things too.


> And I wasn't talking about simple text
> properties that just change faces or the size of the characters, of
> course.  What about properties that need to evaluate Lisp forms or
> depend on Lisp-level variables?


Yes, I know you are talking about this. But AFAICS Mozilla has the
framework to support similar things. Otherwise it could not support
all the things needed to display certain web pages.


>> I guess it does not directly has something that reminds of "special
>> properties", but would that be hard to add?
>
> I have no idea.
>
>> Another point is of course searching for the properties. But Emacs has
>> its own difficulties there (overlays).
>
> The difficulties is not with searching, the difficulties are with
> maintaining many overlays.


I thought the problem was that it takes long time to search for the
overlays at point for example. Is that not the case?