*/ return null;
    private WritableRaster createAlphaRaster() {        final RenderContext ctx = renderCache.getContext();        WritableRaster r = (WritableRaster) ctx.getObject(ALPHA_RASTER);        final int fontSizeUp = (int) (fontSize + 0.5);        if ((r == null) || (r.getWidth() < fontSizeUp)                || (r.getHeight() < fontSizeUp)) {            r = GlyphRenderer.createRaster(fontSizeUp, fontSizeUp);            ctx.setObject(ALPHA_RASTER, r);            Vm.getVm().getCounter(ALPHA_RASTER).inc();        }        return r;    }