[Tips] Android, augmented reality 3D with JPCT + Camera.

[EgonOlsen]

They are hardly comparable IMHO. I had a discussion about some kind of coorperation with the libGDX guys and i'm still thinking of using their buffer related stuff as an option for jPCT-AE once vertex updates become a problem. However, i'm not sure if this is the right place to ask this question...

[androidman]

Hi everyone.

This example use FrameLayout to display 2 layout, but they are still in the same activity. How can we make the same thing with 2 activity (the top one has transparent background)?

   

[androidman]

In my project, i display some 3D models with GLSurfaceView and i use a transparent background SurfaceView on the top to display a small 2D picture on the screen. The problem is the 2D picture cannot display when all 3D models were displayed. If i set invisible for some 3D models, the 2D picture is showned. Is it a memory or framebuffer problem?

[EgonOlsen]

No idea. Personally, i feel that combining OpenGL output with some GUI components is asking for trouble, but maybe i'm just a bit old fashioned here. Do you have a screen shot that shows the problem?

[androidman]

Hi EgonOlsen

i checked my project again. Now, i will descript more detail:
- I used FrameLayout to display a SurfaceView and a GLSurfaceView with SurfaceView is on the top.
- On my test project, everything was fine.
- On my main project, everything works, except SurfaceView cannot display on the top. The differrent thing bettwen the test project and the main project is in the main project , glSufaceView must take a long time to load resources. When i try to set transparenct background for glSurfaceView, i can see a part of SurfaceView at black color areas on glSurfaceView.
- The main project is fine on emulator but on IS03, Nexus I

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    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        SCREEN_WIDTH=getWindowManager().getDefaultDisplay().getWidth();
        SCREEN_HEIGHT=getWindowManager().getDefaultDisplay().getHeight();
       
       requestWindowFeature(Window.FEATURE_NO_TITLE);
       this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
       
       fLayout= new FrameLayout(getApplicationContext());
       
       glSurfaceView =  new GLSurfaceView(getApplication());
       glSurfaceView.setEGLConfigChooser(8, 8, 8, 8, 16, 0);
       glSurfaceView.getHolder().setFormat(PixelFormat.TRANSLUCENT);
   

       renderer= new RendererImplement();
       renderer.loadTextures(getResources());
       glSurfaceView.setRenderer(renderer); 
       
       
       screenSurface= new mySurfaceView(getApplicationContext());
       screenSurface.getHolder().setFormat(PixelFormat.RGBA_8888);
       


       fLayout.addView(screenSurface);
       fLayout.addView(glSurfaceView);
       

       setContentView(fLayout);
       
    }

[androidman]

uhm, I think this is an unknown error when put a surfaceView on the top of a GLSurfaceView. I used a View instead of SurfaceView and eveything is ok with the same code!   

[rhine]

I saw some really nice AR demos this summer at Uplinq. Curious to see if many game devs will utilize this technology especially as device hardware quality/performance improves.

I am thinking of creating an AR-based game next year once I launch my first game.

BTW, its nice to finally be on this forum. Looking forward to developing with JPCT-AE

[K24A3]

Is there a way to play video to a Texture using the Android MediaPlayer API?

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// Load video
MediaPlayer mediaPlayer = MediaPlayer.create(m_context, R.raw.videofile);

// Somehow attach the output to a texture
SurfaceHolder sh = ??? (Texture Surface)
mediaPlayerVid.setDisplay(sh);

// Play video
mediaPlayer.start();



[EgonOlsen]

I'm not sure. If you can make a texture a SurfaceHolder, then maybe...

[K24A3]

I can't seem to find a way to do it, at least efficiently.

GLSurfaceView has a getHolder() function that retrieves the SurfaceHolder.

Perhaps MediaPlayer can render to the OpenGL surface directly?

I tried using mGLView.getHolder() but it crashes. I have yet to check the exception error string but it appears that you need to use callback functions since the GL object runs in a different thread.

[Davi]

How to make the 3D model transform correctly  with AR marker?
I can get the changing  transform matrix,I want to make this transform matrix work with my jpct-ae model.
how to do?do with camera position matrix  or model itself transform matrix?

[EgonOlsen]

This thread contains code to setup your Activity at the beginning as well as code that sets the rotation of the world based on the sensor data (http://www.jpct.net/forum2/index.php/topic,1586.msg11938.html#msg11938). It should actually be sufficient...

[Davi]

what's different between  3d model transforming and world camera transforming?

[EgonOlsen]

Object/model space is the space in which the object itself is in after loading. World space is the space, in which it will be transformed based on it's rotation/translation/... matrices and camera space is the space where it's positioned relative to the camera assuming that the camera is fixed at 0,0,0 looking down z. Think of a camera transformation not as if you were actually moving your head around but as if the world moves around your head, because that's what basically happens in 3D graphics.

[AugTech]

A quick query, or a bug...!

I am doing some of the same as within this thread, but have opted for using the AAConfigChooser as it makes my scene look a lot nicer, but I've lost the transparency so therefore cannot see the camera preview (except on areas of textures!)

In the SurfaceView;

Code Select Expand


    setEGLContextClientVersion(2);
    setEGLConfigChooser(new AAConfigChooser(this));
    getHolder().setFormat(PixelFormat.RGBA_8888);


And then within the renderer onDrawFrame();

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frameBuffer.clear(new RGBColor(0,0,0,0));
theWorld.renderScene(frameBuffer);
theWorld.draw(frameBuffer);
frameBuffer.display();


Does AAConfigChooser() support transparent background, and if so, how?

Incidentally, I have tried PixelFormat.TRANSLUCENT within the SurfaceView to no effect.

thanks.