[android help] How to get a 3D accordion effect on Android

I am planning to port the great 3D accordion effect found on iOS (https://github.com/xyfeng/XYOrigami) on Android.

so far I have something pretty close, here is a screenshot with "pinch-to-fold" to fold the view: http://imageshack.us/photo/my-images/822/3daccordion.png

as you can see, it remains a space between 2 opposite "panels". The process is simple:

1. take the canvas of the main Layout


2. create a Custom surface view which will replace all the view of the layout


3. set as background image the taken canvas


4. cut this canvas into X panels (here 16)


5. redraw the surfaceview with all the "panels" with a calculated matrix


6. recalculate the matrix while pinching to give the "folding effect"

here is the transformation matrix :

private Matrix getFoldingMatrix(int angle, int startFrom,int position) {
    int move = (int) (
        (mWidth - (Math.cos(angle * Math.PI / 180) * mWidth)) * position
    ) +1*position; //overlap of 1px the panels and not get space between panels

    final Camera camera = new Camera();
    final Matrix matrix = new Matrix();
    camera.save();

    camera.rotateY(angle);
    camera.getMatrix(matrix);

    if(position%2==1){
        move += (int) (
            (mWidth - (Math.cos(angle * Math.PI / 180) * mWidth))
        ) ;
        matrix.preTranslate(-mWidth, -mHeight/2);
        matrix.postTranslate(startFrom+mWidth-move, mHeight/2);
    } else {
        matrix.preTranslate(0f, -mHeight/2);
        matrix.postTranslate(startFrom-move, mHeight/2);
    }
    camera.restore();

    return matrix;
}

what am I getting wrong ? why is there still these spaces between opposite "panels"?

.

stackoverflow.comm