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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.


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
/**
 * 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:

    {PathMinX, PathMinY, PathMaxX, PathMaxY}.



/**
     * 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.

/**
     * 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:

    {SpanMinX, SpanMinY, SpanMaxX, SpanMaxY}.



/**
     * 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.

/**
     * 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:

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



/**
     * 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();
}