This approach is more backwards-compatible than the previous attempt.
The onDetachedFromWindow case is unchanged from the "classic"
GLSurfaceView behavior, except that we don't throw a NPE if the
renderer has never been set.
Change-Id: Ia8103a73366ddb13be44f16b789c929e75ddc792
Some devices only support a single active EGL context.
On those devices, when a second activity that uses a GLSurfaceView
is started in the same process, the second activity can potentially
hang in GLSurfaceView.onWindowResize waiting for its GLSurfaceView
render thread to draw a frame. The second activity's render thread
is waiting to acquire an EGL context, but the first activity's render
thread doesn't know it should release the EGL context.
The fix is to detect the potential hang, and ask the first activity's
render thread to release the EGL context.
Change-Id: Ibb342c68772297744c973bcf5010581cd132db67
We believe these errors happen when the window
manager has told surface flinger to close the
native window.
If this error happens while we are creating the
EGL surface we exit the render loop (and
therefore exit the render thread.)
If the error happens while swapping the surface
we ignore it.
In either situation, we expect that the
application is about to be shut down by the
window manager, so it should not be necessary
to try and recover from the error.
with the GLThread.
We used to just set the mPaused state and return,
now we wait until the rendering thread signals
that it has noticed the change in pause state.
This makes Pause/Resume more consistent with
other UI-thread-to-GLThread event communication.
This change was made in the hope of fixing some
race conditions observed in monkey testing.
We now release the EGL context when pausing. This
is required to reduce the chance of running out of
contexts on devices which support a limited number
of active EGL contexts.
Someday we may implement a global EGL context
manager that will allow us to let EGL contexts
persist until another activity needs an EGL
context. But for now, without such a manager,
we take the conservative approach.
Separately, we now terminate EGL when
pausing on Sapphire. This is a requirement of the
Sapphire OpenGL driver.
We now distinguish EGL_CONTEXT_LOST errors from
other kinds of errors. We return "true" if
the swap completes successfully, "false" if
the swap fails due to EGL_CONTEXT_LOST, and
throw a RuntimeException if the swap fails due
to any other cause.
If eglSwapBuffers succeeds, we now avoid calling
eglGetError at all, which means we avoid clearing
any EGL errors that might already have been
pending before eglSwapBuffers is called.
This works around a bug in the
"Q3Dimension MSM7500" driver. That driver only
supports a single active EGLContext, so we must
release and restore the EGLContext when pausing
and unpausing.
Unfortunately the test for deciding whether to
release the context was inverted. We were
releasing the context on every device besides
the MSM7500 devices, which was a performance
drain, and we were not releasing the context on
the MSM7500, which meant the underlying driver
bug was not worked around.
Now we release the EGL context when pausing only
on the devices that have the bug.
The EGL context is now preserved when possible. Previously we would
destroy it whenever the EGL surface was destroyed. Preserving the
EGL context preserves loaded textures and VBO resources.
The problem was a black first frame when creating a surface, or a
garbage frame when the surface was resized.
The cause was lack of synchronization between the render thread and the
UI thread. The UI thread would typically return before the render thread
had a chance to draw its first frame.
The fix was to make the UI thread wait until at least one frame had been
rendered by the rendering thread.
The waiting is done in the surfaceChanged method because we know
that surfaceChanged will be called in both the surface created
and surface changed cases.
Merge commit '85a9498a2f33d62a4313a3561b5468456974696e'
* commit '85a9498a2f33d62a4313a3561b5468456974696e':
Improve the exception message text by including eglGetError().
Merge commit 'ca00dee21425882619aef4ecbe3e0d08de0544e5' into eclair-mr2
* commit 'ca00dee21425882619aef4ecbe3e0d08de0544e5':
Improve the exception message text by including eglGetError().
Provide a new method, GLSurfaceView.setEGLContextClientVersion. Clients
call this method to define which level of OpenGL ES support they want.
This method only affects the default behavior of GLSurfaceView. If clients
have supplied their own EGLContextFactory or EGLConfigChooser then they
are on their own if they want to create an OpenGL ES 2.0 context.
This API is currently hidden.
Update the gl2_java test to use this new API.
Update the gl2_java test's AndroidManifest.xml file to indicate that
it requires OpenGL ES 2.0.
+ The mDone flag is now a pair of flags: mShouldExit and mExited. The
problem with mDone was that it meant "had been asked to exit", but was
being used by some observers as "had exited". Using two variables means
that observers can observe either "had been asked to exit" or "had exited",
as they prefer.
+ Simplyify where we check for mShouldExit. We now check for it at the
top of our innermost guardedRun while loop.
+ requestExitAndWait now waits for mExited to be set to true to know
that a thread has exited, rather than using join(). This means we can use
wait() for the check, which releases the sGLThreadManager
monitor, avoiding a potential deadlock.
+ move the event queue into the sGLThreadManager monitor. This avoids
having to acquire two locks in order to enque/deque events, which also
avoids the potential for lock ordering deadlocks.
+ Simplify the event dequeueing code. We now deque one event each time
through the main GLSurfaceView loop. Events still have priority over
rendering, so there isn't any semantic change, it just cleans up the code.
+ Avoid trying to acquire an egl Surface if we're paused.
+ To simplify reasoning about the code, call sGLThreadManager.notifyAll()
in every case where we modify one of the variables that's protected by
the sGLThreadManager monitor. It would be slightly more efficient to only
notify when we change variables that could cause a thread to wait(), but
then we would have to redo our analysis every time we change any code.
+ Clean up the logic for creating the EGL surface and then calling the
renderer's onSurfaceCreated / onSurfaceChanged methods.
+ Implement work-around for bug 2263168 "Need to draw twice after
screen rotation..."
There were potential deadlocks between the per-GLThread monitors and the
GLThreadManager monitor.
To avoid these deadlocks we now use a single monitor for
both the GLThreadManager state and the per-GLThread state.
Converted GLThreadManager's semaphore into the equivalent
synchronized-wait-notifyAll code. This enables us to wait for
either mDone, or user events, or the EGL surface with a single "wait()".
Simplified the logic used to acquire and release the EGL surface. The
EGL surface is now only requested while the surfaceFlinger surface
is acquired.
Removed the "egl surface stealing" policy we had recently inserted.
It's not needed now that we reliably quit when requested.
Pulled user event processing outside of the GLThreadManager monitor
so that we don't call any potentially-long-running code while
inside the monitor.
This should help with bug 2228262.
We currently only allow one GLThread to have an active EGL Surface at a
time.(This may be lifted in the future, when EGL and GL are reentrant.)
Prior to this change we would enforce this rule by having older GLThreads
quit when a new GLThread started. That had the drawback of leaving the
older GLSurfaceViews in a zombie state -- their GLThreads would be
gone.
We now enforce this rule by just releasing and reacquiring the EGL surface
context as needed.
Specific changes to the code:
created private helper methods - startEgl and stopEgl to help manage
starting and stopping EGL.
Move the calls to sGLThreadManager start and end from the outermost run
method into the startEgl / stopEgl methods.
Reworked the wait loop to handle starting and stopping EGL as needed.
needToWait() gets simpler -- just looks at current status.
sGLThreadManager.shouldQuit was replaced by shouldHaveEgl.
This is another step in fixing bug 2228262.
The code intended to copy the old value of a field, before the
field was updated. However, what the code was actually doing was
copying the new value of the field, after the field was updated.
The fix was to move the copy to before the update.
This is work towards fixing bug 2228262
This is work towards fixing bug 2228262
Specific issues fixed by this change:
+ GLThread names now include the thread id, making it easier to tell one
GLThread from another.
+ A private final static boolean LOG_THREADS can be set to true at compile
time to print out thread-related trace information, helpful for debugging
GLSurfaceView behavior. This static defaults to "false".
+ Changed calls to "notify" to "notifyAll" to make the code more
robust in case more than two threads are blocked on the same monitor.
+ Add a GLThreadManager to help manage the transition to
a new GLThread. Currently only one GLThread can be active in an address
space. When the second thread starts up, the GLThreadManager helps the old
GLThread to shut down,
+ Make sure we stop waiting for dead GLThreads. This is done by adding
checks for a variable mDone being true to our monitor wait loops. And
we use a "finally" clause at the end of GLThread.run() method to set mDone
and notifyAll any wait loops.
Until now we had a race condition where the GL rendering thread could
continue rendering a frame after we have returned from the
SurfaceHolder.Callback.surfaceDestroyed notification.
