Re: [AD] Xwin system bitmaps?

[Michael Bukin <M.A.Bukin@xxxxxxxxxx>]

Thomas Fjellstrom <tfjellstrom@xxxxxxxxxx> writes:

> Someone who knows the Xwin port, would bitmaps that wrap a shm X bmp type be 
> faster than a regular bmp?

Unlikely, because Xwin port has to update 'screen' pixels and not just
window.  It can not just XCopyArea from shm Pixmap to Window, it has
to copy pixels from bitmap data to screen data first (actually, to
shm XImage), then copy XImage to Window.  Maybe, if Xwin port were
using shared memory Pixmap instead of shared memory XImage for screen
data and for video bitmaps, then it might be faster.  It would be much
simpler if Allegro were not allowing read access to screen data.

I tried to use shared memory Pixmaps in old version of XwinAllegro,
but it did not work correctly with them, so I decided to use shared
memory XImages.

-- 
Michael Bukin