Font display scrambled when scrolling

[David Megginson]

Binary package hint: emacs23

When scrolling through a text document or typing in the echo area, fonts often appear scrambled initially, with characters printed on top of each-other. After several seconds of inactivity, the display corrects itself, but the problem will reappear with additional scrolling or typing.

Observed:
- full screen and smaller window
- font-lock on and off
- monospaced and proportional fonts
- with current ~/.emacs file moved out of the way and no .Xdefaults or .Xresources to affect display

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: emacs23 23.1+1-4ubuntu7
ProcVersionSignature: Ubuntu 2.6.32-21.32-generic 2.6.32.11+drm33.2
Uname: Linux 2.6.32-21-generic x86_64
NonfreeKernelModules: wl fglrx
Architecture: amd64
Date: Tue Apr 27 09:32:48 2010
ProcEnviron:
 PATH=(custom, user)
 LANG=en_CA.utf8
 SHELL=/bin/bash
SourcePackage: emacs23

[Phil Lord (phillip-lord)]

I am getting what appears to me to be a highly related bug. I get scrambled, overlapping fonts. In my case, this is not related to scrolling specifically, but occurs even while typing.

As a temporary work-around, I am forcing Emacs to redraw after every command (code below!). Emacs is now usable, although it causes a very unpleasant flicker.

;; nasty hack to fix display issue
(add-hook 'post-command-hook
          'phil-redraw-display-hack)

(defun phil-redraw-display-hack()
  (interactive)
  (redraw-display))

[bartee (bartee-natarajan)]

Any progress or any other workaround on this issue? I am experiencing this on my fresh upgrade to ubuntu 11.04.. emacs 23.2.1

fonts disappear and reappear when scrolling or even while typing as the previous commenter encountered.sh

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.