- If you call onPause() before CreateWindow(), SDLThread will run in infinite loop in background.
- If you call onPause() between a DestroyWindow() and a new CreateWindow(), semaphores are invalids.
SDLActivity.java: the first resume() starts the SDLThread, don't call
nativeResume() as it would post ResumeSem. And the first pause would
automatically be resumed.
- Currently, it tries to Attach the JVM first and update the thread local storage, which are two operations.
Now, it simply gives back the JNI Env stored for the thread.
- Android_JNI_SetupThreadi() should only be used for external.
For internal SDL thread, it's already called in RunThread() (SDL_systhread.c),
and other thread are Java threads which don't need to be attached. i
(even if it doesn't hurt to do it, since it's a no-op).
- JNI_OnLoad is filled with pthread_create, GetEnv, AttachCurrentThread...
It's called for all shared libraries which may don't want this setup,
and loading libraries can be also modified to be done from a static context,
or with relinker. So it's not really clear how, who and what it sets up.
=> Reduce this function to the minimal
SDLThread is a Java Thread, it's not needed to call 'Detach' from the JVM.
Clear mThreadKey, so that the pthread_create destructor is not called for this
thread.
SDLActivity thread priority is unchanged, by default -10 (THREAD_PRIORITY_VIDEO).
SDLAudio thread priority was -4 (SDL_SetThreadPriority was ignored) and is now -16 (THREAD_PRIORITY_AUDIO).
SDLThread thread priority was 0 (THREAD_PRIORITY_DEFAULT) and is -4 (THREAD_PRIORITY_DISPLAY).
- destroy Android_ActivityMutex
- display any SDL error message that may have occured in this thread,
since SDL_GetError() is thread specific, and user has no access to it.
In the usual case, first call to onNativeOrientationChanged() is done before
SDL has been initialised and would just set an error message
"Video subsystem has not been initialized" without sending the event.
Make sure there is not pending Pause accumulated, so the the application doesn't
remain paused and stucked in onDestroy().
Can be tested by adding:
SDLActivity.nativePause();
SDLActivity.nativePause();
mSingleton.finish();
Doesn't seem to happen manually, but symetrical to the pause handling.
Can be tested by adding:
mNextNativeState = SDLActivity.NativeState.PAUSED;
handleNativeState();
mNextNativeState = SDLActivity.NativeState.RESUMED;
handleNativeState();
mNextNativeState = SDLActivity.NativeState.PAUSED;
handleNativeState();
mNextNativeState = SDLActivity.NativeState.RESUMED;
handleNativeState();
Before, it ends in 'paused' state.
Now, it ends in 'resumed' state.
It may happen to have the sequence pause()/resume()/pause(), before polling
any events.
Before, it ends in 'resumed' state because as the check is greedy.
Now, always increase the Pause semaphore, and stop at each pause.
It ends in 'paused' state.
Related to bug 3250: set up a reconfiguration of SurfaceView holder.
Turn the screen off manually before the app starts
(repro rate is not 100%..)
Use a semaphore to prevent concurrency issues between Java Activity and Native thread code, when using 'Android_Window'.
(Eg. Java sending Touch events, while native code is destroying the main SDL_Window. )
Sylvain
SDL_android.c
src/core/android/SDL_android.c:1302:5: warning: variable 'br' is used uninitialized whenever switch default is taken [-Wsometimes-uninitialized]
default:
^~~~~~~
src/core/android/SDL_android.c:1306:12: note: uninitialized use occurs here
return br;
^~
src/core/android/SDL_android.c:1270:12: note: initialize the variable 'br' to silence this warning
jint br;
^
Maybe we could add some basics warning flags, not to see all warnings, but so that new warnings are caught sooner.
I would go for -Wall -Wextra, and some -Wno-warning for the allowed warnings.
Sylvain
Patch a few warnings when using:
-Wmissing-prototypes -Wdocumentation -Wdocumentation-unknown-command
They are automatically enabled with -Wall
Expand SDLActivity::SDLSurface::surfaceChanged() callback to grab the panel width and height at the same time and pass that along to the native code. Only works on API 17+. Duplicates surface dimensions whenever it fails.
Add Android_DeviceWidth/Android_DeviceHeight globals to native code.
Disambiguate Android_ScreenWidth/Android_ScreenHeight -> Android_SurfaceWidth/Android_SurfaceHeight
Use device width/height for all display mode settings.
This is commented out in SDLActivity.java, with the note #CURSORIMPLEENTATION because it requires API 24, which is higher than the minimum required SDK
