In android, when I “minimize” my app with the home button, and then return to it, the display is corrupted. It looks like the display is mixed with the OS display in a very glitchy way.
Any ideas?
I believe Android likes to trash the OpenGL context of apps that are not active.On Mar 20, 2014, at 4:01 AM, tjcbs wrote:
In android, when I “minimize” my app with the home button, and then return to it, the display is corrupted. It looks like the display is mixed with the OS display in a very glitchy way.
Any ideas?
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Alex Szpakowski wrote:
I believe Android likes to trash the OpenGL context of apps that are not active.
I don’t think that is it, I am still rendering normally, the display is just overlaid with corruption.
With past revisions of SDL2 from Mercurial, I had to reinitialise SDL after returning to the foreground. Perhaps you need to do the same? Now, though,
it seems that I do not need to anymore. Then again, I am only using the Renderer API and not explicitly using OpenGL.
As a side note, I remember reading either on this mailing list or in the SDL2 wiki (I cannot remember which) that SDL_RendererPresent() should not be
called when the app is the background (Home button, switching to another app - gallery for instance). Perhaps that is related to your issue as well?
What I have done was when a SDL_APP_WILLENTERBACKGROUND event is received, I set a flag. The main-loop skips calling SDL_RendererPresent() if that
flag is set. This way the app can continue polling for events (e.g. waiting for the SDL_APP_DIDENTERFOREGROUND). Note that the SDL2 wiki states that
these events should be handled by an event filter as stated here http://wiki.libsdl.org/SDL_EventType#Android_and_iOS_Events.
Hope this helps.
Cheers,
AlvinOn 20/03/14 04:37, tjcbs wrote:
Alex Szpakowski wrote:
I believe Android likes to trash the OpenGL context of apps that are not active.I don’t think that is it, I am still rendering normally, the display is just overlaid with corruption.
With past revisions of SDL2 from Mercurial, I had to reinitialise SDL after returning to the foreground. Perhaps you need to do the same? Now, though,
it seems that I do not need to anymore. Then again, I am only using the Renderer API and not explicitly using OpenGL.As a side note, I remember reading either on this mailing list or in the SDL2 wiki (I cannot remember which) that SDL_RendererPresent() should not be
called when the app is the background (Home button, switching to another app - gallery for instance). Perhaps that is related to your issue as well?
What I have done was when a SDL_APP_WILLENTERBACKGROUND event is received, I set a flag. The main-loop skips calling SDL_RendererPresent() if that
flag is set. This way the app can continue polling for events (e.g. waiting for the SDL_APP_DIDENTERFOREGROUND). Note that the SDL2 wiki states that
these events should be handled by an event filter as stated here http://wiki.libsdl.org/SDL_EventType#Android_and_iOS_Events.Hope this helps.
Cheers,
Alvin
I tried handling the background msgs, and unfortunately this did not fix the problem.
How long ago did you stop needing to reinitialize SDL? Did you have to re-create and re-upload all graphics assets? (I am using opengl directly, I assume the renderer api is similar?)
I’m not sure when. Since you are using opengl directly, what you could do is take a look at the internal android code in SDL2 and see what it does
when it emits the SDL_APP_DIDENTERFOREGROUND event. Perhaps you can duplicate that process? Perhaps there is does some opengl dance just before it
emits the event?
AlvinOn 21/03/14 04:35, tjcbs wrote:
Quote:
With past revisions of SDL2 from Mercurial, I had to reinitialise SDL after returning to the foreground. Perhaps you need to do the same? Now, though,
it seems that I do not need to anymore. Then again, I am only using the Renderer API and not explicitly using OpenGL.As a side note, I remember reading either on this mailing list or in the SDL2 wiki (I cannot remember which) that SDL_RendererPresent() should not be
called when the app is the background (Home button, switching to another app - gallery for instance). Perhaps that is related to your issue as well?
What I have done was when a SDL_APP_WILLENTERBACKGROUND event is received, I set a flag. The main-loop skips calling SDL_RendererPresent() if that
flag is set. This way the app can continue polling for events (e.g. waiting for the SDL_APP_DIDENTERFOREGROUND). Note that the SDL2 wiki states that
these events should be handled by an event filter as stated here http://wiki.libsdl.org/SDL_EventType#Android_and_iOS_Events.Hope this helps.
Cheers,
Alvin
I tried handling the background msgs, and unfortunately this did not fix the problem.
How long ago did you stop needing to reinitialize SDL? Did you have to re-create and re-upload all graphics assets? (I am using opengl directly, I
assume the renderer api is similar?)