/// <summary>
/// Returns a unique instance of an ImageFilter object which will
/// actually perform the filtering for the specified ImageConsumer.
/// The default implementation just clones this object.
/// <para>
/// Note: This method is intended to be called by the ImageProducer
/// of the Image whose pixels are being filtered. Developers using
/// this class to filter pixels from an image should avoid calling
/// this method directly since that operation could interfere
/// with the filtering operation.
/// </para>
/// </summary>
/// <param name="ic"> the specified <code>ImageConsumer</code> </param>
/// <returns> an <code>ImageFilter</code> used to perform the
/// filtering for the specified <code>ImageConsumer</code>. </returns>
public virtual ImageFilter GetFilterInstance(ImageConsumer ic)
{
ImageFilter instance = (ImageFilter)Clone();
instance.Consumer = ic;
return(instance);
}
/// <summary>
/// Requests that a given ImageConsumer have the image data delivered
/// one more time in top-down, left-right order. The request is
/// handed to the ImageFilter for further processing, since the
/// ability to preserve the pixel ordering depends on the filter.
///
/// <para>
/// This method is public as a side effect
/// of this class implementing
/// the <code>ImageProducer</code> interface.
/// It should not be called from user code,
/// and its behavior if called from user code is unspecified.
///
/// </para>
/// </summary>
/// <seealso cref= ImageConsumer </seealso>
public virtual void RequestTopDownLeftRightResend(ImageConsumer ic)
{
if (Proxies != null)
{
ImageFilter imgf = (ImageFilter)Proxies[ic];
if (imgf != null)
{
imgf.ResendTopDownLeftRight(Src);
}
}
}
/// <summary>
/// Starts production of the filtered image.
/// If the specified <code>ImageConsumer</code>
/// isn't already a consumer of the filtered image,
/// an instance of the original <code>ImageFilter</code>
/// is created
/// (using the filter's <code>getFilterInstance</code> method)
/// to manipulate the image data
/// for the <code>ImageConsumer</code>.
/// The filter instance for the <code>ImageConsumer</code>
/// is then passed to the <code>startProduction</code> method
/// of the original <code>ImageProducer</code>.
///
/// <para>
/// This method is public as a side effect
/// of this class implementing
/// the <code>ImageProducer</code> interface.
/// It should not be called from user code,
/// and its behavior if called from user code is unspecified.
///
/// </para>
/// </summary>
/// <param name="ic"> the consumer for the filtered image </param>
/// <seealso cref= ImageConsumer </seealso>
public virtual void StartProduction(ImageConsumer ic)
{
if (Proxies == null)
{
Proxies = new Hashtable();
}
ImageFilter imgf = (ImageFilter)Proxies[ic];
if (imgf == null)
{
imgf = Filter.GetFilterInstance(ic);
Proxies[ic] = imgf;
}
Src.StartProduction(imgf);
}
/// <summary>
/// Adds the specified <code>ImageConsumer</code>
/// to the list of consumers interested in data for the filtered image.
/// An instance of the original <code>ImageFilter</code>
/// is created
/// (using the filter's <code>getFilterInstance</code> method)
/// to manipulate the image data
/// for the specified <code>ImageConsumer</code>.
/// The newly created filter instance
/// is then passed to the <code>addConsumer</code> method
/// of the original <code>ImageProducer</code>.
///
/// <para>
/// This method is public as a side effect
/// of this class implementing
/// the <code>ImageProducer</code> interface.
/// It should not be called from user code,
/// and its behavior if called from user code is unspecified.
///
/// </para>
/// </summary>
/// <param name="ic"> the consumer for the filtered image </param>
/// <seealso cref= ImageConsumer </seealso>
public virtual void AddConsumer(ImageConsumer ic)
{
lock (this)
{
if (Proxies == null)
{
Proxies = new Hashtable();
}
if (!Proxies.ContainsKey(ic))
{
ImageFilter imgf = Filter.GetFilterInstance(ic);
Proxies[ic] = imgf;
Src.AddConsumer(imgf);
}
}
}
/// <summary>
/// Removes an ImageConsumer from the list of consumers interested in
/// data for this image.
///
/// <para>
/// This method is public as a side effect
/// of this class implementing
/// the <code>ImageProducer</code> interface.
/// It should not be called from user code,
/// and its behavior if called from user code is unspecified.
///
/// </para>
/// </summary>
/// <seealso cref= ImageConsumer </seealso>
public virtual void RemoveConsumer(ImageConsumer ic)
{
lock (this)
{
if (Proxies != null)
{
ImageFilter imgf = (ImageFilter)Proxies[ic];
if (imgf != null)
{
Src.RemoveConsumer(imgf);
Proxies.Remove(ic);
if (Proxies.Count == 0)
{
Proxies = null;
}
}
}
}
}
/// <summary>
/// Constructs an ImageProducer object from an existing ImageProducer
/// and a filter object. </summary>
/// <param name="orig"> the specified <code>ImageProducer</code> </param>
/// <param name="imgf"> the specified <code>ImageFilter</code> </param>
/// <seealso cref= ImageFilter </seealso>
/// <seealso cref= java.awt.Component#createImage </seealso>
public FilteredImageSource(ImageProducer orig, ImageFilter imgf)
{
Src = orig;
Filter = imgf;
}
