package org.litesoft.render;

import org.litesoft.core.*;

public interface RenderableRect
{
    /**
     * This is a helper method so that Parent Containers can notify their Children that someplace "up"
     * the RenderableRect Graph there was a change in the Rendering Participation.
     * <p/>
     * As this method is a helper, it is not gaurenteed to be called on all Rendering Participation Changes, as there
     * may be platform specific methods that do some or all of the notification (e.g. Attached and Detached).
     * <p/>
     * When coding this method it is important to notify your children (if you have any) and your two RenderHelpers.
     * To facilitate this
     *
     * @see org.litesoft.render.RenderingParticipationChangedHelper
     */
    public void renderingParticipationChanged();

    /**
     * Get the RenderHelper for "this" for the X dimension.
     *
     * @return !null
     */
    public RenderHelper getRenderHelperX();

    /**
     * Get the RenderHelper for "this" for the Y dimension.
     *
     * @return !null
     */
    public RenderHelper getRenderHelperY();

    public static final RenderableRect NULL_RR = new NullRenderableRect();

    public static class NullRenderableRect extends AbstractNullObject implements RenderableRect
    {
        public void renderingParticipationChanged()
        {
        }

        public RenderHelper getRenderHelperX()
        {
            throw whatThe( "getRenderHelperX" );
        }

        public RenderHelper getRenderHelperY()
        {
            throw whatThe( "getRenderHelperY" );
        }
    }
}