Android libGDX flickering

[devemux86]

Android libGDX sometimes flickers and jitters when panning / zooming.

Related to #149.

[devemux86]

The issue can be more clearly observed if we enable the continuous rendering in GdxMap.create():

Gdx.graphics.setContinuousRendering(true);

[devemux86]

Among the various settings of AndroidApplicationConfiguration in MainActivity this seems to help:

cfg.numSamples = 2;

[RootSoft]

It seems
cfg.numSamples = 2;
is helping a little bit. but the camera is still acting up/weird when panning/zooming/rotating.

What about clearing the screen in your render method?

@Override
    public void render(float delta) {

        if (!mRenderRequest)
            return;

        //clear screen
        Gdx.gl.glClearColor(1, 1, 1, 1);
        Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);

        mMapRenderer.onDrawFrame();
    }

This seems to help also, but again the camera is sometimes jittering/flickering.

[devemux86]

Which render do you mean, in GdxMap?

Regarding clearing see also #5, where a fix was needed for the desktop.

Side note: we have multiple platforms sharing a common code, so need to be very careful with any change in the core modules, like vtm or vtm-gdx.

[RootSoft]

Yes, the one in GdxMap. I've been putting all my code in a GdxMapScreen so I can handle different screens on my Game. I don't have any jittery effects anymore, but sometimes the camera (viewport) is acting strange.

[devemux86]

Made a quick test with just the clear, the result is the same with flickering.

[RootSoft]

Mhmm yes indeed, thought it was fixed but after a while it started flickering again.
Holding in (touching) the screen without doing anything else, shakes the camera little bot too.

[devemux86]

@RootSoft on what device(s) do you see the flicker?

Because I'm able to see it on Nexus 9 but not on Samsung Galaxy Tab 4 7.0 LTE (Android 5.1.1).

[RootSoft]

I'm using an Elephone P9000 (Android 6.0).

[devemux86]

I enabled MSAA in example to check it in action.

[RootSoft]

I've uploaded a video showcasing the flicker and camera issue here.

Using the following settings:

AndroidApplicationConfiguration cfg = new AndroidApplicationConfiguration();
cfg.stencil = 8;
cfg.numSamples = 2;
Gdx.graphics.setContinuousRendering(false);

As you can see, the tree's are sometimes flickering and not rendering for 1/2 seconds too. Don't know if it's related to this issue.
EDIT: the flickering seems to happen when resuming from a paused state. If i hold the screen, it starts flickering. As soon as I start moving, the flickering stops.

[devemux86]

Thanks for the visual feedback, it always helps understanding better.
That's what I saw and with the MSAA not happening anymore.
Here flicker appears on the whole map and trees of course follow.

[devemux86]

@RootSoft have you tried desktop libGDX #149, how is the behavior there and on what OS?

[RootSoft]

I haven't tried it on desktop yet since I haven't configured the LibGDX desktop side yet. I'll notify once I've tried it there

[glensimar]

Hi Guys! I have this jittering/flickering efects sometimes when i tried to include seamarks to map, and it seems that user the same icon for all seamarks, i use a rendertheme from mapsforge (i don't know if this works) with some changes.. But this happened in version 5.1 or lower.. i android 6 works nice..

[devemux86]

GdxMap.render has a check to skip renders. If we comment it, then works without flickering (no MSAA needed).