[SOLVED] Font characters being "smudged", obscured

[Punchcutter]

I recently did an emerge world, and am now having a very strange problem. Some font characters are not being rendered properly (in KDE). They are covered with black "smudges" (it's hard to find a better word to describe it), which are sometimes rectangular, or partly so, but not always. The smudges are not fixed and permanent, but can be made to go away by (for example) scrolling the web page up and down (if they're on a web page), mousing over them, or selecting them. For example, in Thunderbird mail, if you select the message that has these characters in its Subject, they will "clean up" and display properly.

This machine makes heavy use of Japanese, and Japanese text is most affected by this, but not exclusively. Some English text is affected if it's (say) on an HTML form button. Also, the KDM login page is covered with smudges (all English).

Has anyone ever seen this? Could it possibly be related to the upgrade of xorg-server to >1.5 ? I'm imagining it's connected to some low-level library like cairo or pango, perhaps? I'm not sure what sort of information I could provide would be useful, so I'll leave it at this and see what people have to say.

Many thanks in advance for any hints or clues, no matter how remote and tentative, you can provide.

Dave

[sebaro]

using nvidia-drivers? https://forums.gentoo.org/viewtopic-t-769826-highlight-.html

[Punchcutter]

That was it! Thanks very much.

Dave

[timeBandit]

Moved from Desktop Environments to Duplicate Threads.
See topic linked above.
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