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	/*
	* Copyright (c) 1998, 2013, 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.
	*/

	/*
	* @author Charlton Innovations, Inc.
	*/

	package java.awt.font;

	import java.awt.RenderingHints;
	import static java.awt.RenderingHints.*;
	import java.awt.geom.AffineTransform;

	/**
	* The <code>FontRenderContext</code> class is a container for the
	* information needed to correctly measure text. The measurement of text
	* can vary because of rules that map outlines to pixels, and rendering
	* hints provided by an application.
	* <p>
	* One such piece of information is a transform that scales
	* typographical points to pixels. (A point is defined to be exactly 1/72
	* of an inch, which is slightly different than
	* the traditional mechanical measurement of a point.) A character that
	* is rendered at 12pt on a 600dpi device might have a different size
	* than the same character rendered at 12pt on a 72dpi device because of
	* such factors as rounding to pixel boundaries and hints that the font
	* designer may have specified.
	* <p>
	* Anti-aliasing and Fractional-metrics specified by an application can also
	* affect the size of a character because of rounding to pixel
	* boundaries.
	* <p>
	* Typically, instances of <code>FontRenderContext</code> are
	* obtained from a {@link java.awt.Graphics2D Graphics2D} object. A
	* <code>FontRenderContext</code> which is directly constructed will
	* most likely not represent any actual graphics device, and may lead
	* to unexpected or incorrect results.
	* @see java.awt.RenderingHints#KEY_TEXT_ANTIALIASING
	* @see java.awt.RenderingHints#KEY_FRACTIONALMETRICS
	* @see java.awt.Graphics2D#getFontRenderContext()
	* @see java.awt.font.LineMetrics
	*/

	public class FontRenderContext {
	private transient AffineTransform tx;
	private transient Object aaHintValue;
	private transient Object fmHintValue;
	private transient boolean defaulting;

	/**
	* Constructs a new <code>FontRenderContext</code>
	* object.
	*
	*/
	protected FontRenderContext() {
	aaHintValue = VALUE_TEXT_ANTIALIAS_DEFAULT;
	fmHintValue = VALUE_FRACTIONALMETRICS_DEFAULT;
	defaulting = true;
	}

	/**
	* Constructs a <code>FontRenderContext</code> object from an
	* optional {@link AffineTransform} and two <code>boolean</code>
	* values that determine if the newly constructed object has
	* anti-aliasing or fractional metrics.
	* In each case the boolean values <CODE>true</CODE> and <CODE>false</CODE>
	* correspond to the rendering hint values <CODE>ON</CODE> and
	* <CODE>OFF</CODE> respectively.
	* <p>
	* To specify other hint values, use the constructor which
	* specifies the rendering hint values as parameters :
	* {@link #FontRenderContext(AffineTransform, Object, Object)}.
	* @param tx the transform which is used to scale typographical points
	* to pixels in this <code>FontRenderContext</code>. If null, an
	* identity transform is used.
	* @param isAntiAliased determines if the newly constructed object
	* has anti-aliasing.
	* @param usesFractionalMetrics determines if the newly constructed
	* object has fractional metrics.
	*/
	public FontRenderContext(AffineTransform tx,
	boolean isAntiAliased,
	boolean usesFractionalMetrics) {
	if (tx != null && !tx.isIdentity()) {
	this.tx = new AffineTransform(tx);
	}
	if (isAntiAliased) {
	aaHintValue = VALUE_TEXT_ANTIALIAS_ON;
	} else {
	aaHintValue = VALUE_TEXT_ANTIALIAS_OFF;
	}
	if (usesFractionalMetrics) {
	fmHintValue = VALUE_FRACTIONALMETRICS_ON;
	} else {
	fmHintValue = VALUE_FRACTIONALMETRICS_OFF;
	}
	}

	/**
	* Constructs a <code>FontRenderContext</code> object from an
	* optional {@link AffineTransform} and two <code>Object</code>
	* values that determine if the newly constructed object has
	* anti-aliasing or fractional metrics.
	* @param tx the transform which is used to scale typographical points
	* to pixels in this <code>FontRenderContext</code>. If null, an
	* identity transform is used.
	* @param aaHint - one of the text antialiasing rendering hint values
	* defined in {@link java.awt.RenderingHints java.awt.RenderingHints}.
	* Any other value will throw <code>IllegalArgumentException</code>.
	* {@link java.awt.RenderingHints#VALUE_TEXT_ANTIALIAS_DEFAULT VALUE_TEXT_ANTIALIAS_DEFAULT}
	* may be specified, in which case the mode used is implementation
	* dependent.
	* @param fmHint - one of the text fractional rendering hint values defined
	* in {@link java.awt.RenderingHints java.awt.RenderingHints}.
	* {@link java.awt.RenderingHints#VALUE_FRACTIONALMETRICS_DEFAULT VALUE_FRACTIONALMETRICS_DEFAULT}
	* may be specified, in which case the mode used is implementation
	* dependent.
	* Any other value will throw <code>IllegalArgumentException</code>
	* @throws IllegalArgumentException if the hints are not one of the
	* legal values.
	* @since 1.6
	*/
	public FontRenderContext(AffineTransform tx, Object aaHint, Object fmHint){
	if (tx != null && !tx.isIdentity()) {
	this.tx = new AffineTransform(tx);
	}
	try {
	if (KEY_TEXT_ANTIALIASING.isCompatibleValue(aaHint)) {
	aaHintValue = aaHint;
	} else {
	throw new IllegalArgumentException("AA hint:" + aaHint);
	}
	} catch (Exception e) {
	throw new IllegalArgumentException("AA hint:" +aaHint);
	}
	try {
	if (KEY_FRACTIONALMETRICS.isCompatibleValue(fmHint)) {
	fmHintValue = fmHint;
	} else {
	throw new IllegalArgumentException("FM hint:" + fmHint);
	}
	} catch (Exception e) {
	throw new IllegalArgumentException("FM hint:" +fmHint);
	}
	}

	/**
	* Indicates whether or not this <code>FontRenderContext</code> object
	* measures text in a transformed render context.
	* @return <code>true</code> if this <code>FontRenderContext</code>
	* object has a non-identity AffineTransform attribute.
	* <code>false</code> otherwise.
	* @see java.awt.font.FontRenderContext#getTransform
	* @since 1.6
	*/
	public boolean isTransformed() {
	if (!defaulting) {
	return tx != null;
	} else {
	return !getTransform().isIdentity();
	}
	}

	/**
	* Returns the integer type of the affine transform for this
	* <code>FontRenderContext</code> as specified by
	* {@link java.awt.geom.AffineTransform#getType()}
	* @return the type of the transform.
	* @see AffineTransform
	* @since 1.6
	*/
	public int getTransformType() {
	if (!defaulting) {
	if (tx == null) {
	return AffineTransform.TYPE_IDENTITY;
	} else {
	return tx.getType();
	}
	} else {
	return getTransform().getType();
	}
	}

	/**
	* Gets the transform that is used to scale typographical points
	* to pixels in this <code>FontRenderContext</code>.
	* @return the <code>AffineTransform</code> of this
	* <code>FontRenderContext</code>.
	* @see AffineTransform
	*/
	public AffineTransform getTransform() {
	return (tx == null) ? new AffineTransform() : new AffineTransform(tx);
	}

	/**
	* Returns a boolean which indicates whether or not some form of
	* antialiasing is specified by this <code>FontRenderContext</code>.
	* Call {@link #getAntiAliasingHint() getAntiAliasingHint()}
	* for the specific rendering hint value.
	* @return <code>true</code>, if text is anti-aliased in this
	* <code>FontRenderContext</code>; <code>false</code> otherwise.
	* @see java.awt.RenderingHints#KEY_TEXT_ANTIALIASING
	* @see #FontRenderContext(AffineTransform,boolean,boolean)
	* @see #FontRenderContext(AffineTransform,Object,Object)
	*/
	public boolean isAntiAliased() {
	return !(aaHintValue == VALUE_TEXT_ANTIALIAS_OFF \|\|
	aaHintValue == VALUE_TEXT_ANTIALIAS_DEFAULT);
	}

	/**
	* Returns a boolean which whether text fractional metrics mode
	* is used in this <code>FontRenderContext</code>.
	* Call {@link #getFractionalMetricsHint() getFractionalMetricsHint()}
	* to obtain the corresponding rendering hint value.
	* @return <code>true</code>, if layout should be performed with
	* fractional metrics; <code>false</code> otherwise.
	* in this <code>FontRenderContext</code>.
	* @see java.awt.RenderingHints#KEY_FRACTIONALMETRICS
	* @see #FontRenderContext(AffineTransform,boolean,boolean)
	* @see #FontRenderContext(AffineTransform,Object,Object)
	*/
	public boolean usesFractionalMetrics() {
	return !(fmHintValue == VALUE_FRACTIONALMETRICS_OFF \|\|
	fmHintValue == VALUE_FRACTIONALMETRICS_DEFAULT);
	}

	/**
	* Return the text anti-aliasing rendering mode hint used in this
	* <code>FontRenderContext</code>.
	* This will be one of the text antialiasing rendering hint values
	* defined in {@link java.awt.RenderingHints java.awt.RenderingHints}.
	* @return text anti-aliasing rendering mode hint used in this
	* <code>FontRenderContext</code>.
	* @since 1.6
	*/
	public Object getAntiAliasingHint() {
	if (defaulting) {
	if (isAntiAliased()) {
	return VALUE_TEXT_ANTIALIAS_ON;
	} else {
	return VALUE_TEXT_ANTIALIAS_OFF;
	}
	}
	return aaHintValue;
	}

	/**
	* Return the text fractional metrics rendering mode hint used in this
	* <code>FontRenderContext</code>.
	* This will be one of the text fractional metrics rendering hint values
	* defined in {@link java.awt.RenderingHints java.awt.RenderingHints}.
	* @return the text fractional metrics rendering mode hint used in this
	* <code>FontRenderContext</code>.
	* @since 1.6
	*/
	public Object getFractionalMetricsHint() {
	if (defaulting) {
	if (usesFractionalMetrics()) {
	return VALUE_FRACTIONALMETRICS_ON;
	} else {
	return VALUE_FRACTIONALMETRICS_OFF;
	}
	}
	return fmHintValue;
	}

	/**
	* Return true if obj is an instance of FontRenderContext and has the same
	* transform, antialiasing, and fractional metrics values as this.
	* @param obj the object to test for equality
	* @return <code>true</code> if the specified object is equal to
	* this <code>FontRenderContext</code>; <code>false</code>
	* otherwise.
	*/
	public boolean equals(Object obj) {
	try {
	return equals((FontRenderContext)obj);
	}
	catch (ClassCastException e) {
	return false;
	}
	}

	/**
	* Return true if rhs has the same transform, antialiasing,
	* and fractional metrics values as this.
	* @param rhs the <code>FontRenderContext</code> to test for equality
	* @return <code>true</code> if <code>rhs</code> is equal to
	* this <code>FontRenderContext</code>; <code>false</code>
	* otherwise.
	* @since 1.4
	*/
	public boolean equals(FontRenderContext rhs) {
	if (this == rhs) {
	return true;
	}
	if (rhs == null) {
	return false;
	}

	/* if neither instance is a subclass, reference values directly. */
	if (!rhs.defaulting && !defaulting) {
	if (rhs.aaHintValue == aaHintValue &&
	rhs.fmHintValue == fmHintValue) {

	return tx == null ? rhs.tx == null : tx.equals(rhs.tx);
	}
	return false;
	} else {
	return
	rhs.getAntiAliasingHint() == getAntiAliasingHint() &&
	rhs.getFractionalMetricsHint() == getFractionalMetricsHint() &&
	rhs.getTransform().equals(getTransform());
	}
	}

	/**
	* Return a hashcode for this FontRenderContext.
	*/
	public int hashCode() {
	int hash = tx == null ? 0 : tx.hashCode();
	/* SunHints value objects have identity hashcode, so we can rely on
	* this to ensure that two equal FRC's have the same hashcode.
	*/
	if (defaulting) {
	hash += getAntiAliasingHint().hashCode();
	hash += getFractionalMetricsHint().hashCode();
	} else {
	hash += aaHintValue.hashCode();
	hash += fmHintValue.hashCode();
	}
	return hash;
	}
	}

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