[maemo-developers] HildonRemoteTexture "tearing"/"flicker"

From: Javier S. Pedro maemo at javispedro.com
Date: Tue Jan 12 15:47:34 EET 2010
Hi all,

I am doing some experiments on using HildonRemoteTexture from a bare
X11/SDL app -- basically to get sgx accelerated scaling in apps that
wouldn't otherwise use the sgx for anything else. It works, but there
seems to be some race condition where the compositor is reading the
shared memory area _before_ I send the damage client event to the
remote texture X window. This of course cause visible tearing or even
flicker if the texture is drawn while (for example) the SNES emulator
is just in the middle of rendering any of the background layers, which
tends to happen often depending on CPU load / framerate.

Note I'm using HildonRemoteTexture instead of AnimationActor because I
need no rotation nor any of the actor features and using H-R-T is
slightly simpler -- no need to use any of the MIT-SHM functions. But I
have to wonder, seeing how the H-R-T API is falling behind if it is
going to be deprecated in the future.

Feel free to comment on whether this is a good approach or not, too.

Eero wrote:
> hildon-desktop automatically switches to composited mode when needed.

Hopefully this includes "having a child animation actor / remote texture" :)

Javier.
More information about the maemo-developers mailing list