Finding the center (xy) of a OMText?

Hello

I'm trying to implement clustering of locations a'la google maps marker clustering. But I'm having difficulties finding the exact center (xy) of the OMText which represents the clustering count. This causes a slight misalignment of the icons sitting behind the count.

Here is my code from generate:

        label.generate(proj);
        label.prepareForRender(g);
        if (label.getPolyBounds() != null) {
            Rectangle rect = label.getPolyBounds().getBounds();
            rh = (int) ((float) (bounds.getHeight() - currentFontDescent / 2));
            rw = (int) rect.getWidth();
            int width = raster.getImage().getWidth(null);
            int height = raster.getImage().getHeight(null);
            raster.setRenderType(OMGraphicConstants.RENDERTYPE_XY);
            double cX = label.getMapLocation().getX() + rw / 2;
            double cY = label.getMapLocation().getY() + currentFontDescent / 2;
            raster.setX((int) (cX - width / 2));
            raster.setY((int) (cY - height / 2));

I tried with getCenterX/Y on getPolyBounds but the result varies with the font size and length of the string being rendered. It seems to work best with string length > 1.

I would like to use

FontMetrics metrics = g.getFontMetrics();
Rectangle2D rect = metrics.getStringBounds(text, g);

but I guess this does not work with OMText and the way it does text rendering.

Any hints?

Thanks
Carsten