xrender + xorg 7.2 broke?

Carsten Haitzler (The Rasterman) raster at rasterman.com
Fri Sep 7 22:21:04 PDT 2007

ok- interesting here.

is this meant to work? (it always did until recently i swear, and it still
works with closed nvidia drivers, but not open via drivers, closed fglrx, nor

* take xrender picture - ARGB (with alpha channel).
* render to it and set alpha channel
* create 1 bit deep xrender image
* copy ARGB picture to 1 bit picture

the result used to be (and still is with nvidia drivers) that the ALPHA channel
in the ARGB picture is stripped out and converted to 1bit (ie reduced to A >>
7 per pixel so if alpha >= 128 bitmap is 1, otherwise 0), so the alpha channel
for any xrender picture can be used to convert to a bitmap easily and then used
for other evil things (shaped windows, window input shape mask etc.)

i this valid? i swear it always worked when i wrote it on all drivers i tried,
etc., but it seems to have stopped working. it was nice and convenient.

so was this ever meant to work? if so... i suspect we may have a regression of

------------- Codito, ergo sum - "I code, therefore I am" --------------
The Rasterman (Carsten Haitzler)    raster at rasterman.com
Tokyo, Japan (東京 日本)

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