| /* | |
| * 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} 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} are | |
| * obtained from a {@link java.awt.Graphics2D Graphics2D} object. A | |
| * {@code FontRenderContext} 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} | |
| * object. | |
| * | |
| */ | |
| protected FontRenderContext() { | |
| aaHintValue = VALUE_TEXT_ANTIALIAS_DEFAULT; | |
| fmHintValue = VALUE_FRACTIONALMETRICS_DEFAULT; | |
| defaulting = true; | |
| } | |
| /** | |
| * Constructs a {@code FontRenderContext} object from an | |
| * optional {@link AffineTransform} and two {@code boolean} | |
| * values that determine if the newly constructed object has | |
| * anti-aliasing or fractional metrics. | |
| * In each case the boolean values {@code true} and {@code false} | |
| * correspond to the rendering hint values {@code ON} and | |
| * {@code OFF} 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}. 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} object from an | |
| * optional {@link AffineTransform} and two {@code Object} | |
| * 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}. 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}. | |
| * {@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} | |
| * @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} object | |
| * measures text in a transformed render context. | |
| * @return {@code true} if this {@code FontRenderContext} | |
| * object has a non-identity AffineTransform attribute. | |
| * {@code false} 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} 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}. | |
| * @return the {@code AffineTransform} of this | |
| * {@code FontRenderContext}. | |
| * @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}. | |
| * Call {@link #getAntiAliasingHint() getAntiAliasingHint()} | |
| * for the specific rendering hint value. | |
| * @return {@code true}, if text is anti-aliased in this | |
| * {@code FontRenderContext}; {@code false} 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}. | |
| * Call {@link #getFractionalMetricsHint() getFractionalMetricsHint()} | |
| * to obtain the corresponding rendering hint value. | |
| * @return {@code true}, if layout should be performed with | |
| * fractional metrics; {@code false} otherwise. | |
| * in this {@code FontRenderContext}. | |
| * @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}. | |
| * 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}. | |
| * @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}. | |
| * 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}. | |
| * @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} if the specified object is equal to | |
| * this {@code FontRenderContext}; {@code false} | |
| * 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} to test for equality | |
| * @return {@code true} if {@code rhs} is equal to | |
| * this {@code FontRenderContext}; {@code false} | |
| * 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; | |
| } | |
| } |