// Whether or not a component is double buffered is a
                // bit tricky with Swing. This gives a good approximation
                // of the various ways to turn on double buffering for
                // components.
                return true;
            }
        }
        // Don't do true double buffering.
        return false;
    }

    /**
     * Turns off double buffering per window.
     */
    private void resetDoubleBufferPerWindow() {
        if (bufferInfos != null) {
            dispose(bufferInfos);
            bufferInfos = null;
            repaintManager.setPaintManager(null);
        }
    }

    /**
     * Returns the BufferInfo for the specified root or null if one
     * hasn't been created yet.
     */
    private BufferInfo getBufferInfo(Container root) {
        for (int counter = bufferInfos.size() - 1; counter >= 0; counter--) {
            BufferInfo bufferInfo = bufferInfos.get(counter);
            Container biRoot = bufferInfo.getRoot();
            if (biRoot == null) {
                // Window gc'ed
                bufferInfos.remove(counter);
                if (LOGGER.isLoggable(Level.FINER)) {
                    LOGGER.finer("BufferInfo pruned, root null");
                }
            }
            else if (biRoot == root) {
                return bufferInfo;
            }
        }
        return null;
    }

    private void accumulate(int x, int y, int w, int h) {
        accumulatedX = Math.min(x, accumulatedX);
        accumulatedY = Math.min(y, accumulatedY);
        accumulatedMaxX = Math.max(accumulatedMaxX, x + w);
        accumulatedMaxY = Math.max(accumulatedMaxY, y + h);
    }



    /**
     * BufferInfo is used to track the BufferStrategy being used for
     * a particular Component.  In addition to tracking the BufferStrategy
     * it will install a WindowListener and ComponentListener.  When the
     * component is hidden/iconified the buffer is marked as needing to be
     * completely repainted.
     */
    private class BufferInfo extends ComponentAdapter implements
                               WindowListener {
        // NOTE: This class does NOT hold a direct reference to the root, if it
        // did there would be a cycle between the BufferPerWindowPaintManager
        // and the Window so that it could never be GC'ed
        //
        // Reference to BufferStrategy is referenced via WeakReference for
        // same reason.
        private WeakReference<BufferStrategy> weakBS;
        private WeakReference<Container> root;
        // Whether or not we're using flip bs or blit.
        private boolean usingFlip;
        // Indicates whether or not the backbuffer and display are in sync.
        // This is set to true when a full repaint on the rootpane is done.
        private boolean inSync;
        // Indicates the contents were lost during and expose event.
        private boolean contentsLostDuringExpose;
        // Indicates we need to generate a paint event on expose.
        private boolean paintAllOnExpose;


        public BufferInfo(Container root) {
            this.root = new WeakReference<Container>(root);
            root.addComponentListener(this);
            if (root instanceof Window) {
                ((Window)root).addWindowListener(this);
            }
        }

        public void setPaintAllOnExpose(boolean paintAllOnExpose) {
            this.paintAllOnExpose = paintAllOnExpose;
        }

        public boolean getPaintAllOnExpose() {
            return paintAllOnExpose;
        }

        public void setContentsLostDuringExpose(boolean value) {
            contentsLostDuringExpose = value;
        }