|
From: | Dmitry Antipov |
Subject: | bug#15555: Re: bug#15555: 24.3; Bidirectional display very slow with long lines |
Date: | Wed, 19 Feb 2014 14:49:39 +0400 |
User-agent: | Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.3.0 |
On 02/18/2014 09:42 PM, Eli Zaretskii wrote:
Anyway, just moving cursor horizontally cannot possibly be slow due to bidi, especially as long as point stays in the same screenful. The redisplay becomes unbearably slow with long lines only when you either scroll the display (e.g., C-v) or for vertical cursor motion, because these require the display engine to traverse many buffer positions, many more than is needed to just move the cursor, and it currently can only start that traversal from the beginning of a physical line.
1) I realize that vertical motion is slower than horizontal, but [2] from http://debbugs.gnu.org/cgi/bugreport.cgi?bug=15555#65 shows that the major slowdown happens when cursor is moved horizontally (by right-char) within the same line. 2) (setq bidi-display-reordering nil) helps bug15555 to run over 4000.txt just as expected. Dmitry
[Prev in Thread] | Current Thread | [Next in Thread] |