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	/*
	* Copyright (c) 2005, 2006, 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 javax.swing.plaf.nimbus;

	import java.awt.Graphics;
	import java.awt.Image;
	import java.awt.Insets;

	/**
	* ImageScalingHelper
	*
	* @author Created by Jasper Potts (Aug 8, 2007)
	*/
	class ImageScalingHelper {

	/** Enumeration for the types of painting this class can handle. */
	enum PaintType {
	/**
	* Painting type indicating the image should be centered in the space provided. When used the <code>mask</code>
	* is ignored.
	*/
	CENTER,

	/**
	* Painting type indicating the image should be tiled across the specified width and height. When used the
	* <code>mask</code> is ignored.
	*/
	TILE,

	/**
	* Painting type indicating the image should be split into nine regions with the top, left, bottom and right
	* areas stretched.
	*/
	PAINT9_STRETCH,

	/**
	* Painting type indicating the image should be split into nine regions with the top, left, bottom and right
	* areas tiled.
	*/
	PAINT9_TILE
	}

	;

	private static final Insets EMPTY_INSETS = new Insets(0, 0, 0, 0);

	static final int PAINT_TOP_LEFT = 1;
	static final int PAINT_TOP = 2;
	static final int PAINT_TOP_RIGHT = 4;
	static final int PAINT_LEFT = 8;
	static final int PAINT_CENTER = 16;
	static final int PAINT_RIGHT = 32;
	static final int PAINT_BOTTOM_RIGHT = 64;
	static final int PAINT_BOTTOM = 128;
	static final int PAINT_BOTTOM_LEFT = 256;
	/**
	* Specifies that all regions should be painted. If this is set any other regions specified will not be painted.
	* For example PAINT_ALL \| PAINT_CENTER will paint all but the center.
	*/
	static final int PAINT_ALL = 512;

	/**
	* Paints using the algorightm specified by <code>paintType</code>.
	*
	* @param g Graphics to render to
	* @param x X-coordinate
	* @param y Y-coordinate
	* @param w Width to render to
	* @param h Height to render to
	* @param image Image to render from, if <code>null</code> this method will do nothing
	* @param sInsets Insets specifying the portion of the image that will be stretched or tiled, if <code>null</code>
	* empty <code>Insets</code> will be used.
	* @param dInsets Destination insets specifying the portion of the image will be stretched or tiled, if
	* <code>null</code> empty <code>Insets</code> will be used.
	* @param paintType Specifies what type of algorithm to use in painting
	* @param mask Specifies portion of image to render, if <code>PAINT_ALL</code> is specified, any other regions
	* specified will not be painted, for example PAINT_ALL \| PAINT_CENTER paints everything but the
	* center.
	*/
	public static void paint(Graphics g, int x, int y, int w, int h,
	Image image, Insets sInsets,
	Insets dInsets, PaintType paintType, int mask) {
	if (image == null \|\| image.getWidth(null) <= 0 \|\| image.getHeight(null) <= 0) {
	return;
	}
	if (sInsets == null) {
	sInsets = EMPTY_INSETS;
	}
	if (dInsets == null) {
	dInsets = EMPTY_INSETS;
	}
	int iw = image.getWidth(null);
	int ih = image.getHeight(null);

	if (paintType == PaintType.CENTER) {
	// Center the image
	g.drawImage(image, x + (w - iw) / 2,
	y + (h - ih) / 2, null);
	} else if (paintType == PaintType.TILE) {
	// Tile the image
	int lastIY = 0;
	for (int yCounter = y, maxY = y + h; yCounter < maxY;
	yCounter += (ih - lastIY), lastIY = 0) {
	int lastIX = 0;
	for (int xCounter = x, maxX = x + w; xCounter < maxX;
	xCounter += (iw - lastIX), lastIX = 0) {
	int dx2 = Math.min(maxX, xCounter + iw - lastIX);
	int dy2 = Math.min(maxY, yCounter + ih - lastIY);
	g.drawImage(image, xCounter, yCounter, dx2, dy2,
	lastIX, lastIY, lastIX + dx2 - xCounter,
	lastIY + dy2 - yCounter, null);
	}
	}
	} else {
	int st = sInsets.top;
	int sl = sInsets.left;
	int sb = sInsets.bottom;
	int sr = sInsets.right;

	int dt = dInsets.top;
	int dl = dInsets.left;
	int db = dInsets.bottom;
	int dr = dInsets.right;

	// Constrain the insets to the size of the image
	if (st + sb > ih) {
	db = dt = sb = st = Math.max(0, ih / 2);
	}
	if (sl + sr > iw) {
	dl = dr = sl = sr = Math.max(0, iw / 2);
	}

	// Constrain the insets to the size of the region we're painting
	// in.
	if (dt + db > h) {
	dt = db = Math.max(0, h / 2 - 1);
	}
	if (dl + dr > w) {
	dl = dr = Math.max(0, w / 2 - 1);
	}

	boolean stretch = (paintType == PaintType.PAINT9_STRETCH);
	if ((mask & PAINT_ALL) != 0) {
	mask = (PAINT_ALL - 1) & ~mask;
	}

	if ((mask & PAINT_LEFT) != 0) {
	drawChunk(image, g, stretch, x, y + dt, x + dl, y + h - db,
	0, st, sl, ih - sb, false);
	}
	if ((mask & PAINT_TOP_LEFT) != 0) {
	drawImage(image, g, x, y, x + dl, y + dt,
	0, 0, sl, st);
	}
	if ((mask & PAINT_TOP) != 0) {
	drawChunk(image, g, stretch, x + dl, y, x + w - dr, y + dt,
	sl, 0, iw - sr, st, true);
	}
	if ((mask & PAINT_TOP_RIGHT) != 0) {
	drawImage(image, g, x + w - dr, y, x + w, y + dt,
	iw - sr, 0, iw, st);
	}
	if ((mask & PAINT_RIGHT) != 0) {
	drawChunk(image, g, stretch,
	x + w - dr, y + dt, x + w, y + h - db,
	iw - sr, st, iw, ih - sb, false);
	}
	if ((mask & PAINT_BOTTOM_RIGHT) != 0) {
	drawImage(image, g, x + w - dr, y + h - db, x + w, y + h,
	iw - sr, ih - sb, iw, ih);
	}
	if ((mask & PAINT_BOTTOM) != 0) {
	drawChunk(image, g, stretch,
	x + dl, y + h - db, x + w - dr, y + h,
	sl, ih - sb, iw - sr, ih, true);
	}
	if ((mask & PAINT_BOTTOM_LEFT) != 0) {
	drawImage(image, g, x, y + h - db, x + dl, y + h,
	0, ih - sb, sl, ih);
	}
	if ((mask & PAINT_CENTER) != 0) {
	drawImage(image, g, x + dl, y + dt, x + w - dr, y + h - db,
	sl, st, iw - sr, ih - sb);
	}
	}
	}

	/**
	* Draws a portion of an image, stretched or tiled.
	*
	* @param image Image to render.
	* @param g Graphics to render to
	* @param stretch Whether the image should be stretched or timed in the
	* provided space.
	* @param dx1 X origin to draw to
	* @param dy1 Y origin to draw to
	* @param dx2 End x location to draw to
	* @param dy2 End y location to draw to
	* @param sx1 X origin to draw from
	* @param sy1 Y origin to draw from
	* @param sx2 Max x location to draw from
	* @param sy2 Max y location to draw from
	* @param xDirection Used if the image is not stretched. If true it
	* indicates the image should be tiled along the x axis.
	*/
	private static void drawChunk(Image image, Graphics g, boolean stretch,
	int dx1, int dy1, int dx2, int dy2, int sx1,
	int sy1, int sx2, int sy2,
	boolean xDirection) {
	if (dx2 - dx1 <= 0 \|\| dy2 - dy1 <= 0 \|\| sx2 - sx1 <= 0 \|\|
	sy2 - sy1 <= 0) {
	// Bogus location, nothing to paint
	return;
	}
	if (stretch) {
	g.drawImage(image, dx1, dy1, dx2, dy2, sx1, sy1, sx2, sy2, null);
	}
	else {
	int xSize = sx2 - sx1;
	int ySize = sy2 - sy1;
	int deltaX;
	int deltaY;

	if (xDirection) {
	deltaX = xSize;
	deltaY = 0;
	}
	else {
	deltaX = 0;
	deltaY = ySize;
	}
	while (dx1 < dx2 && dy1 < dy2) {
	int newDX2 = Math.min(dx2, dx1 + xSize);
	int newDY2 = Math.min(dy2, dy1 + ySize);

	g.drawImage(image, dx1, dy1, newDX2, newDY2,
	sx1, sy1, sx1 + newDX2 - dx1,
	sy1 + newDY2 - dy1, null);
	dx1 += deltaX;
	dy1 += deltaY;
	}
	}
	}

	private static void drawImage(Image image, Graphics g,
	int dx1, int dy1, int dx2, int dy2, int sx1,
	int sy1, int sx2, int sy2) {
	// PENDING: is this necessary, will G2D do it for me?
	if (dx2 - dx1 <= 0 \|\| dy2 - dy1 <= 0 \|\| sx2 - sx1 <= 0 \|\|
	sy2 - sy1 <= 0) {
	// Bogus location, nothing to paint
	return;
	}
	g.drawImage(image, dx1, dy1, dx2, dy2, sx1, sy1, sx2, sy2, null);
	}


	}

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