The issue you filed focuses on touch event handling, but I see
flickering just as much with trackball events.  If it is a fundamental
thread scheduling issue, I guess it wouldn't matter the type or even
frequency of events being generated.

On Oct 5, 2:01 pm, Tom Gibara <[email protected]> wrote:
> I just read your post. Looks like I hit the same problem about 6 months ago.
> I even managed to create a mostly-reproducible test case so that I could
> file an issue:http://code.google.com/p/android/issues/detail?id=1956
>
> (I can only think that it's some sort of fairness issue with monitors)
>
> <http://code.google.com/p/android/issues/detail?id=1956>My solution was in
> the same spirit, but actually uses a simple synchronization-free circular
> event buffer that instead uses volatiles to guarantee correct execution.
>
> Tom.
>
> 2009/10/5 Robert Green <[email protected]>
>
>
>
> > I just thought of something.  You said your logic thread sleeps?  Are
> > you using RENDERMODE_CONTINUOUSLY?
>
> > Here's a shot in the dark.  I feel like your renderer isn't clearing
> > the color buffer and isn't drawing anything, and that maybe happens
> > when there's a certain state of the logic thread somehow.  Drawing a
> > frame without clearing the color buffer and without drawing anything
> > will make for some wild flickering but the image will still be there,
> > just flickery.  I noticed that when I was messing with skyboxes and
> > had my clear command off.
>
> > By the way, I don't recommend handling input the way you are.  I
> > switched all my games to use input pipelines and they have saved me a
> > load of trouble.  I get super fast response and don't have to
> > synchronize with a common thread mutex, which I have always had issues
> > with it not giving up the lock to another thread.  I wrote an article
> > just now that you can take a look at if you're interested in switching
> > -http://www.rbgrn.net/content/342-using-input-pipelines-your-android-game
>
> > On Oct 5, 9:27 am, Jeremy Slade <[email protected]> wrote:
> > > I'm definitely not getting anywhere close to that limit
> > > (GL_MAX_ELEMENTS_VERTICES).
>
> > > I'm pretty close to a root cause for at least a large percentage of
> > > the flickering events... It has something to do with my thread
> > > synchronization, but it's not obvious to me how it causes the flicker.
>
> > > I have three threads:
> > > * main / UI thread
> > > * logic thread
> > > * rendering thread (created by GLSurfaceView)
>
> > > The majority of the flickering happens when I do something to generate
> > > UI events (touch the screen, move the trackball, etc).  I end up
> > > passing a message to the logic thread, which may be sleeping:
>
> > >     public void queueGameEvent(GameEvent ev) {
> > >         synchronized(mGameLoop) {
> > >             if ( first_event != null ) first_event.next_event = ev;
> > >             else first_event = ev;
> > >             ev.next_event = null;
> > >             //mGameLoop.notifyAll(); // wake sleeping threads
> > >         }
> > >     }
>
> > > When I have the notfyAll() call enabled, it flickers badly.  Without
> > > it, I rarely see flickers (still some, though).  That method is called
> > > from the UI thread, and should result in waking up the logic thread.
> > > Any ideas on how / why that affects the rendering?
>
> > > Thanks,
> > > Jeremy
>
> > > On Oct 4, 6:05 pm, Robert Green <[email protected]> wrote:
>
> > > > The G1 reports 65536 for that parameter.
>
> > > > On Oct 4, 7:06 am, RichardC <[email protected]> wrote:
>
> > > > > You could try
>
> > > > > glGetIntegerv(GL_MAX_ELEMENTS_VERTICES, &value);
>
> > > > > Have not tried this myself but found it in
>
> > > > >http://gpwiki.org/forums/viewtopic.php?t=8839
>
> > > > > On Oct 4, 7:36 am, Jeremy Slade <[email protected]> wrote:
>
> > > > > > I did wonder about the OpenGL command buffer limit -- any way to
> > > > > > verify for sure that I am hitting it?
>
> > > > > > I would be surprised if that's the case, though -- it's not a real
> > > > > > complex scene, maybe 3000-4000 textured triangles.  But I'll admit
> > to
> > > > > > being almost a complete novice where OpenGL is concerned...
>
> > > > > > The various meshes are all done with glDrawElements().  95% of this
> > is
> > > > > > in the cow mesh -- same mesh drawn w/ different transforms, and
> > > > > > different textures bound each time.  The mesh itself uses ~54k of
> > > > > > memory for vertices + normals + tex coords.  How big is the OpenGL
> > > > > > buffer?  seems like it's got to be significantly larger than that.
>
> > > > > > On Oct 3, 1:29 pm, RichardC <[email protected]>
> > wrote:
>
> > > > > > > If I remember correctly OpenGL internally has a limit to the
> > number of
> > > > > > > items it can hold in it's display list.  When the list gets full
> > it's
> > > > > > > starts drawing rather than dropping your items.  To achieve this
> > it
> > > > > > > flips the buffers and draws the remaining items on the live
> > screen.
>
> > > > > > > If I am remembering correcly this could explain what you are
> > seeing.
>
> > > > > > > --
> > > > > > > Ruchard
>
> > > > > > > On Oct 3, 8:08 pm, Jeremy Slade <[email protected]>
> > wrote:
>
> > > > > > > > I'm trying to clean up some rendering issues for a 3D game --
> > > > > > > > CowPotato (http://www.cyrket.com/package/
> > > > > > > > com.froogloid.android.cowpotato).  I could use some help on one
> > issue.
>
> > > > > > > > Basically I'm seeing some flickering, like the next frame is
> > getting
> > > > > > > > flushed before everything is drawn.  It is definitely the last
> > few
> > > > > > > > items in my display list that seem to flicker -- if I reorder
> > the
> > > > > > > > list, it's always the last part of the list that flickers.
>
> > > > > > > > I understand that the GLSurfaceView automatically provides
> > double-
> > > > > > > > buffering -- it certainly appears to be the case looking at the
> > > > > > > > source.  So any suggestions as to why I might be seeing
> > flicker?  I
> > > > > > > > put counters into the drawing methods to make sure that all the
> > > > > > > > objects are called each frame, they just don't show up on
> > screen all
> > > > > > > > the time.
>
> > > > > > > > Any insight would be appreciated.
>
> > > > > > > > Jeremy
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