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	/*
	* Copyright (c) 1998, 2007, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package sun.java2d.pipe;

	import java.awt.geom.PathIterator;
	import java.awt.Rectangle;
	import sun.awt.geom.PathConsumer2D;

	/**
	* This class can iterate individual span elements generated by scan
	* converting a Shape.
	* This particular implementation flattens the incoming path and then
	* performs simple polygon tracing to calculate the spans.
	*
	* Note that this class holds pointers to native data which must be
	* disposed. It is not marked as finalizable since it is intended
	* to be very lightweight and finalization is a comparitively expensive
	* procedure. The caller must specifically use try{} finally{} to
	* manually ensure that the object is disposed after use, otherwise
	* native data structures might be leaked.
	*
	* Here is a code sample for using this class:
	*
	* public void fillShape(Shape s, Rectangle clipRect) {
	* ShapeSpanIterator ssi = new ShapeSpanIterator(false);
	* try {
	* ssi.setOutputArea(clipRect);
	* ssi.appendPath(s.getPathIterator(null));
	* int spanbox[] = new int[4];
	* while (ssi.nextSpan(spanbox)) {
	* int x = spanbox[0];
	* int y = spanbox[1];
	* int w = spanbox[2] - x;
	* int h = spanbox[3] - y;
	* fillRect(x, y, w, h);
	* }
	* } finally {
	* ssi.dispose();
	* }
	* }
	*/
	public final class ShapeSpanIterator
	implements SpanIterator, PathConsumer2D
	{
	long pData;

	static {
	initIDs();
	}

	public static native void initIDs();

	public ShapeSpanIterator(boolean adjust) {
	setNormalize(adjust);
	}

	/*
	* Appends the geometry and winding rule from the indicated
	* path iterator.
	*/
	public void appendPath(PathIterator pi) {
	float coords[] = new float[6];

	setRule(pi.getWindingRule());
	while (!pi.isDone()) {
	addSegment(pi.currentSegment(coords), coords);
	pi.next();
	}
	pathDone();
	}

	/*
	* Appends the geometry from the indicated set of polygon points.
	*/
	public native void appendPoly(int xPoints[], int yPoints[], int nPoints,
	int xoff, int yoff);

	/*
	* Sets the normalization flag so that incoming data is
	* adjusted to nearest (0.25, 0.25) subpixel position.
	*/
	private native void setNormalize(boolean adjust);

	/*
	* Sets the rectangle of interest for storing and returning
	* span segments.
	*/
	public void setOutputAreaXYWH(int x, int y, int w, int h) {
	setOutputAreaXYXY(x, y, Region.dimAdd(x, w), Region.dimAdd(y, h));
	}

	/*
	* Sets the rectangle of interest for storing and returning
	* span segments.
	*/
	public native void setOutputAreaXYXY(int lox, int loy, int hix, int hiy);

	/*
	* Sets the rectangle of interest for storing and returning
	* span segments to the specified Rectangle.
	*/
	public void setOutputArea(Rectangle r) {
	setOutputAreaXYWH(r.x, r.y, r.width, r.height);
	}

	/*
	* Sets the rectangle of interest for storing and returning
	* span segments to the bounds of the specified Region.
	*/
	public void setOutputArea(Region r) {
	setOutputAreaXYXY(r.lox, r.loy, r.hix, r.hiy);
	}

	/*
	* Sets the winding rule in the native data structures.
	*/
	public native void setRule(int rule);

	/*
	* Adds a single PathIterator segment to the internal list of
	* path element structures.
	*/
	public native void addSegment(int type, float coords[]);

	/*
	* Gets the bbox of the available path segments, clipped to the
	* OutputArea.
	*/
	public native void getPathBox(int pathbox[]);

	/*
	* Intersects the path box with the given bbox.
	* Returned spans are clipped to this region, or discarded
	* altogether if they lie outside it.
	*/
	public native void intersectClipBox(int lox, int loy, int hix, int hiy);

	/*
	* Fetches the next span that needs to be operated on.
	* If the return value is false then there are no more spans.
	*/
	public native 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.
	*/
	public native 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 native long getNativeIterator();

	/*
	* Cleans out all internal data structures.
	*/
	public native void dispose();

	public native void moveTo(float x, float y);
	public native void lineTo(float x, float y);
	public native void quadTo(float x1, float y1,
	float x2, float y2);
	public native void curveTo(float x1, float y1,
	float x2, float y2,
	float x3, float y3);
	public native void closePath();
	public native void pathDone();
	public native long getNativeConsumer();
	}

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