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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

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 * accompanied this code).

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package sun.java2d.pipe;

/**

 * This interface defines a general method for iterating through the

 * rectangular "spans" that represent the interior of a filled path.

 * <p>

 * There can be many kinds of span iterators used in the rendering

 * pipeline, the most basic being an iterator that scan converts a

 * path defined by any PathIterator, or an nested iterator which

 * intersects another iterator's spans with a clip region.

 * Other iterators can be created for scan converting some of the

 * primitive shapes more explicitly for speed or quality.

 *

 * @author Jim Graham

 */

public interface SpanIterator {

    /**

     * This method returns the bounding box of the spans that the

     * iterator will be returning.

     * The array must be of length at least 4 and upon return, it

     * will be filled with the values:

     * <pre>

     *     {PathMinX, PathMinY, PathMaxX, PathMaxY}.

     * </pre>

     */

    public void getPathBox(int pathbox[]);

    /**

     * This method constrains the spans returned by nextSpan() to the

     * rectangle whose bounds are given.

     */

    public void intersectClipBox(int lox, int loy, int hix, int hiy);

    /**

     * This method returns the next span in the shape being iterated.

     * The array must be of length at least 4 and upon return, it

     * will be filled with the values:

     * <pre>

     *     {SpanMinX, SpanMinY, SpanMaxX, SpanMaxY}.

     * </pre>

     */

    public boolean nextSpan(int spanbox[]);

    /**

     * This method tells the iterator that it may skip all spans

     * whose Y range is completely above the indicated Y coordinate.

     * This method is used to provide feedback from the caller when

     * clipping prevents the display of any data in a given Y range.

     * Typically it will only be called when this iterator has returned

     * a span whose MaxY coordinate is less than the indicated Y and

     * the calling mechanism wants to avoid unnecessary iteration work.

     * While this request could technically be ignored (i.e. a NOP),

     * doing so could potentially cause the caller to make this callback

     * for each span that is being skipped.

     */

    public void skipDownTo(int y);

    /**

     * This method returns a native pointer to a function block that

     * can be used by a native method to perform the same iteration

     * cycle that the above methods provide while avoiding upcalls to

     * the Java object.

     * The definition of the structure whose pointer is returned by

     * this method is defined in:

     * <pre>

     *     src/share/native/sun/java2d/pipe/SpanIterator.h

     * </pre>

     */

    public long getNativeIterator();

}