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third-party-mirror/openjdk/jdk25u/HEAD/./src/java.desktop/share/classes/java/awt/font/TextLayout.java
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/*
* Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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*
* This code is distributed in the hope that it will be useful, but WITHOUT
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* accompanied this code).
*
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/*
* (C) Copyright Taligent, Inc. 1996 - 1997, All Rights Reserved
* (C) Copyright IBM Corp. 1996-2003, All Rights Reserved
*
* The original version of this source code and documentation is
* copyrighted and owned by Taligent, Inc., a wholly-owned subsidiary
* of IBM. These materials are provided under terms of a License
* Agreement between Taligent and Sun. This technology is protected
* by multiple US and International patents.
*
* This notice and attribution to Taligent may not be removed.
* Taligent is a registered trademark of Taligent, Inc.
*
*/
package java.awt.font;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.Shape;
import java.awt.font.NumericShaper;
import java.awt.font.TextLine.TextLineMetrics;
import java.awt.geom.AffineTransform;
import java.awt.geom.GeneralPath;
import java.awt.geom.NoninvertibleTransformException;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.text.AttributedString;
import java.text.AttributedCharacterIterator;
import java.text.AttributedCharacterIterator.Attribute;
import java.text.CharacterIterator;
import java.util.Map;
import java.util.HashMap;
import java.util.Hashtable;
import sun.font.AttributeValues;
import sun.font.CodePointIterator;
import sun.font.CoreMetrics;
import sun.font.Decoration;
import sun.font.FontLineMetrics;
import sun.font.FontResolver;
import sun.font.GraphicComponent;
import sun.font.LayoutPathImpl;
/**
*
* {@code TextLayout} is an immutable graphical representation of styled
* character data.
* <p>
* It provides the following capabilities:
* <ul>
* <li>implicit bidirectional analysis and reordering,
* <li>cursor positioning and movement, including split cursors for
* mixed directional text,
* <li>highlighting, including both logical and visual highlighting
* for mixed directional text,
* <li>multiple baselines (roman, hanging, and centered),
* <li>hit testing,
* <li>justification,
* <li>default font substitution,
* <li>metric information such as ascent, descent, and advance, and
* <li>rendering
* </ul>
* <p>
* A {@code TextLayout} object can be rendered using
* its {@code draw} method.
* <p>
* {@code TextLayout} can be constructed either directly or through
* the use of a {@link LineBreakMeasurer}. When constructed directly, the
* source text represents a single paragraph. {@code LineBreakMeasurer}
* allows styled text to be broken into lines that fit within a particular
* width. See the {@code LineBreakMeasurer} documentation for more
* information.
* <p>
* {@code TextLayout} construction logically proceeds as follows:
* <ul>
* <li>paragraph attributes are extracted and examined,
* <li>text is analyzed for bidirectional reordering, and reordering
* information is computed if needed,
* <li>text is segmented into style runs
* <li>fonts are chosen for style runs, first by using a font if the
* attribute {@link TextAttribute#FONT} is present, otherwise by computing
* a default font using the attributes that have been defined
* <li>if text is on multiple baselines, the runs or subruns are further
* broken into subruns sharing a common baseline,
* <li>glyphvectors are generated for each run using the chosen font,
* <li>final bidirectional reordering is performed on the glyphvectors
* </ul>
* <p>
* All graphical information returned from a {@code TextLayout}
* object's methods is relative to the origin of the
* {@code TextLayout}, which is the intersection of the
* {@code TextLayout} object's baseline with its left edge. Also,
* coordinates passed into a {@code TextLayout} object's methods
* are assumed to be relative to the {@code TextLayout} object's
* origin. Clients usually need to translate between a
* {@code TextLayout} object's coordinate system and the coordinate
* system in another object (such as a
* {@link java.awt.Graphics Graphics} object).
* <p>
* {@code TextLayout} objects are constructed from styled text,
* but they do not retain a reference to their source text. Thus,
* changes in the text previously used to generate a {@code TextLayout}
* do not affect the {@code TextLayout}.
* <p>
* Three methods on a {@code TextLayout} object
* ({@code getNextRightHit}, {@code getNextLeftHit}, and
* {@code hitTestChar}) return instances of {@link TextHitInfo}.
* The offsets contained in these {@code TextHitInfo} objects
* are relative to the start of the {@code TextLayout}, <b>not</b>
* to the text used to create the {@code TextLayout}. Similarly,
* {@code TextLayout} methods that accept {@code TextHitInfo}
* instances as parameters expect the {@code TextHitInfo} object's
* offsets to be relative to the {@code TextLayout}, not to any
* underlying text storage model.
* <p>
* <strong>Examples</strong>:<p>
* Constructing and drawing a {@code TextLayout} and its bounding
* rectangle:
* <blockquote><pre>
* Graphics2D g = ...;
* Point2D loc = ...;
* Font font = Font.getFont("Helvetica-bold-italic");
* FontRenderContext frc = g.getFontRenderContext();
* TextLayout layout = new TextLayout("This is a string", font, frc);
* layout.draw(g, (float)loc.getX(), (float)loc.getY());
*
* Rectangle2D bounds = layout.getBounds();
* bounds.setRect(bounds.getX()+loc.getX(),
* bounds.getY()+loc.getY(),
* bounds.getWidth(),
* bounds.getHeight());
* g.draw(bounds);
* </pre>
* </blockquote>
* <p>
* Hit-testing a {@code TextLayout} (determining which character is at
* a particular graphical location):
* <blockquote><pre>
* Point2D click = ...;
* TextHitInfo hit = layout.hitTestChar(
* (float) (click.getX() - loc.getX()),
* (float) (click.getY() - loc.getY()));
* </pre>
* </blockquote>
* <p>
* Responding to a right-arrow key press:
* <blockquote><pre>
* int insertionIndex = ...;
* TextHitInfo next = layout.getNextRightHit(insertionIndex);
* if (next != null) {
* // translate graphics to origin of layout on screen
* g.translate(loc.getX(), loc.getY());
* Shape[] carets = layout.getCaretShapes(next.getInsertionIndex());
* g.draw(carets[0]);
* if (carets[1] != null) {
* g.draw(carets[1]);
* }
* }
* </pre></blockquote>
* <p>
* Drawing a selection range corresponding to a substring in the source text.
* The selected area may not be visually contiguous:
* <blockquote><pre>
* // selStart, selLimit should be relative to the layout,
* // not to the source text
*
* int selStart = ..., selLimit = ...;
* Color selectionColor = ...;
* Shape selection = layout.getLogicalHighlightShape(selStart, selLimit);
* // selection may consist of disjoint areas
* // graphics is assumed to be translated to origin of layout
* g.setColor(selectionColor);
* g.fill(selection);
* </pre></blockquote>
* <p>
* Drawing a visually contiguous selection range. The selection range may
* correspond to more than one substring in the source text. The ranges of
* the corresponding source text substrings can be obtained with
* {@code getLogicalRangesForVisualSelection()}:
* <blockquote><pre>
* TextHitInfo selStart = ..., selLimit = ...;
* Shape selection = layout.getVisualHighlightShape(selStart, selLimit);
* g.setColor(selectionColor);
* g.fill(selection);
* int[] ranges = getLogicalRangesForVisualSelection(selStart, selLimit);
* // ranges[0], ranges[1] is the first selection range,
* // ranges[2], ranges[3] is the second selection range, etc.
* </pre></blockquote>
* <p>
* Note: Font rotations can cause text baselines to be rotated, and
* multiple runs with different rotations can cause the baseline to
* bend or zig-zag. In order to account for this (rare) possibility,
* some APIs are specified to return metrics and take parameters 'in
* baseline-relative coordinates' (e.g. ascent, advance), and others
* are in 'in standard coordinates' (e.g. getBounds). Values in
* baseline-relative coordinates map the 'x' coordinate to the
* distance along the baseline, (positive x is forward along the
* baseline), and the 'y' coordinate to a distance along the
* perpendicular to the baseline at 'x' (positive y is 90 degrees
* clockwise from the baseline vector). Values in standard
* coordinates are measured along the x and y axes, with 0,0 at the
* origin of the TextLayout. Documentation for each relevant API
* indicates what values are in what coordinate system. In general,
* measurement-related APIs are in baseline-relative coordinates,
* while display-related APIs are in standard coordinates.
*
* @see LineBreakMeasurer
* @see TextAttribute
* @see TextHitInfo
* @see LayoutPath
*/
public final class TextLayout implements Cloneable {
private int characterCount;
private boolean isVerticalLine = false;
private byte baseline;
private float[] baselineOffsets; // why have these ?
private TextLine textLine;
// cached values computed from GlyphSets and set info:
// all are recomputed from scratch in buildCache()
private TextLine.TextLineMetrics lineMetrics = null;
private float visibleAdvance;
/*
* TextLayouts are supposedly immutable. If you mutate a TextLayout under
* the covers (like the justification code does) you'll need to set this
* back to false. Could be replaced with textLine != null <--> cacheIsValid.
*/
private boolean cacheIsValid = false;
// This value is obtained from an attribute, and constrained to the
// interval [0,1]. If 0, the layout cannot be justified.
private float justifyRatio;
// If a layout is produced by justification, then that layout
// cannot be justified. To enforce this constraint the
// justifyRatio of the justified layout is set to this value.
private static final float ALREADY_JUSTIFIED = -53.9f;
// dx and dy specify the distance between the TextLayout's origin
// and the origin of the leftmost GlyphSet (TextLayoutComponent,
// actually). They were used for hanging punctuation support,
// which is no longer implemented. Currently they are both always 0,
// and TextLayout is not guaranteed to work with non-zero dx, dy
// values right now. They were left in as an aide and reminder to
// anyone who implements hanging punctuation or other similar stuff.
// They are static now so they don't take up space in TextLayout
// instances.
private static float dx;
private static float dy;
/*
* Natural bounds is used internally. It is built on demand in
* getNaturalBounds.
*/
private Rectangle2D naturalBounds = null;
/*
* boundsRect encloses all of the bits this TextLayout can draw. It
* is build on demand in getBounds.
*/
private Rectangle2D boundsRect = null;
/*
* flag to suppress/allow carets inside of ligatures when hit testing or
* arrow-keying
*/
private boolean caretsInLigaturesAreAllowed = false;
/**
* Defines a policy for determining the strong caret location.
* This class contains one method, {@code getStrongCaret}, which
* is used to specify the policy that determines the strong caret in
* dual-caret text. The strong caret is used to move the caret to the
* left or right. Instances of this class can be passed to
* {@code getCaretShapes}, {@code getNextLeftHit} and
* {@code getNextRightHit} to customize strong caret
* selection.
* <p>
* To specify alternate caret policies, subclass {@code CaretPolicy}
* and override {@code getStrongCaret}. {@code getStrongCaret}
* should inspect the two {@code TextHitInfo} arguments and choose
* one of them as the strong caret.
* <p>
* Most clients do not need to use this class.
*/
public static class CaretPolicy {
/**
* Constructs a {@code CaretPolicy}.
*/
public CaretPolicy() {
}
/**
* Chooses one of the specified {@code TextHitInfo} instances as
* a strong caret in the specified {@code TextLayout}.
* @param hit1 a valid hit in {@code layout}
* @param hit2 a valid hit in {@code layout}
* @param layout the {@code TextLayout} in which
* {@code hit1} and {@code hit2} are used
* @return {@code hit1} or {@code hit2}
* (or an equivalent {@code TextHitInfo}), indicating the
* strong caret.
*/
public TextHitInfo getStrongCaret(TextHitInfo hit1,
TextHitInfo hit2,
TextLayout layout) {
// default implementation just calls private method on layout
return layout.getStrongHit(hit1, hit2);
}
}
/**
* This {@code CaretPolicy} is used when a policy is not specified
* by the client. With this policy, a hit on a character whose direction
* is the same as the line direction is stronger than a hit on a
* counterdirectional character. If the characters' directions are
* the same, a hit on the leading edge of a character is stronger
* than a hit on the trailing edge of a character.
*/
public static final CaretPolicy DEFAULT_CARET_POLICY = new CaretPolicy();
/**
* Constructs a {@code TextLayout} from a {@code String}
* and a {@link Font}. All the text is styled using the specified
* {@code Font}.
* <p>
* The {@code String} must specify a single paragraph of text,
* because an entire paragraph is required for the bidirectional
* algorithm.
* @param string the text to display
* @param font a {@code Font} used to style the text
* @param frc contains information about a graphics device which is needed
* to measure the text correctly.
* Text measurements can vary slightly depending on the
* device resolution, and attributes such as antialiasing. This
* parameter does not specify a translation between the
* {@code TextLayout} and user space.
*/
public TextLayout(String string, Font font, FontRenderContext frc) {
if (font == null) {
throw new IllegalArgumentException("Null font passed to TextLayout constructor.");
}
if (string == null) {
throw new IllegalArgumentException("Null string passed to TextLayout constructor.");
}
if (string.length() == 0) {
throw new IllegalArgumentException("Zero length string passed to TextLayout constructor.");
}
Map<? extends Attribute, ?> attributes = null;
if (font.hasLayoutAttributes()) {
attributes = font.getAttributes();
}
char[] text = string.toCharArray();
if (sameBaselineUpTo(font, text, 0, text.length) == text.length) {
fastInit(text, font, attributes, frc);
} else {
AttributedString as = attributes == null
? new AttributedString(string)
: new AttributedString(string, attributes);
as.addAttribute(TextAttribute.FONT, font);
standardInit(as.getIterator(), text, frc);
}
}
/**
* Constructs a {@code TextLayout} from a {@code String}
* and an attribute set.
* <p>
* All the text is styled using the provided attributes.
* <p>
* {@code string} must specify a single paragraph of text because an
* entire paragraph is required for the bidirectional algorithm.
* @param string the text to display
* @param attributes the attributes used to style the text
* @param frc contains information about a graphics device which is needed
* to measure the text correctly.
* Text measurements can vary slightly depending on the
* device resolution, and attributes such as antialiasing. This
* parameter does not specify a translation between the
* {@code TextLayout} and user space.
*/
public TextLayout(String string, Map<? extends Attribute,?> attributes,
FontRenderContext frc)
{
if (string == null) {
throw new IllegalArgumentException("Null string passed to TextLayout constructor.");
}
if (attributes == null) {
throw new IllegalArgumentException("Null map passed to TextLayout constructor.");
}
if (string.length() == 0) {
throw new IllegalArgumentException("Zero length string passed to TextLayout constructor.");
}
char[] text = string.toCharArray();
Font font = singleFont(text, 0, text.length, attributes);
if (font != null) {
fastInit(text, font, attributes, frc);
} else {
AttributedString as = new AttributedString(string, attributes);
standardInit(as.getIterator(), text, frc);
}
}
/*
* Determines a font for the attributes, and if a single font can render
* all the text on one baseline, return it, otherwise null. If the
* attributes specify a font, assume it can display all the text without
* checking.
* If the AttributeSet contains an embedded graphic, return null.
*/
private static Font singleFont(char[] text,
int start,
int limit,
Map<? extends Attribute, ?> attributes) {
if (attributes.get(TextAttribute.CHAR_REPLACEMENT) != null) {
return null;
}
Font font = null;
try {
font = (Font)attributes.get(TextAttribute.FONT);
}
catch (ClassCastException e) {
}
if (font == null) {
if (attributes.get(TextAttribute.FAMILY) != null) {
font = Font.getFont(attributes);
if (font.canDisplayUpTo(text, start, limit) != -1) {
return null;
}
} else {
FontResolver resolver = FontResolver.getInstance();
CodePointIterator iter = CodePointIterator.create(text, start, limit);
int fontIndex = resolver.nextFontRunIndex(iter);
if (iter.charIndex() == limit) {
font = resolver.getFont(fontIndex, attributes);
}
}
}
if (sameBaselineUpTo(font, text, start, limit) != limit) {
return null;
}
return font;
}
/**
* Constructs a {@code TextLayout} from an iterator over styled text.
* <p>
* The iterator must specify a single paragraph of text because an
* entire paragraph is required for the bidirectional
* algorithm.
* @param text the styled text to display
* @param frc contains information about a graphics device which is needed
* to measure the text correctly.
* Text measurements can vary slightly depending on the
* device resolution, and attributes such as antialiasing. This
* parameter does not specify a translation between the
* {@code TextLayout} and user space.
*/
public TextLayout(AttributedCharacterIterator text, FontRenderContext frc) {
if (text == null) {
throw new IllegalArgumentException("Null iterator passed to TextLayout constructor.");
}
int start = text.getBeginIndex();
int limit = text.getEndIndex();
if (start == limit) {
throw new IllegalArgumentException("Zero length iterator passed to TextLayout constructor.");
}
int len = limit - start;
text.first();
char[] chars = new char[len];
int n = 0;
for (char c = text.first();
c != CharacterIterator.DONE;
c = text.next())
{
chars[n++] = c;
}
text.first();
if (text.getRunLimit() == limit) {
Map<? extends Attribute, ?> attributes = text.getAttributes();
Font font = singleFont(chars, 0, len, attributes);
if (font != null) {
fastInit(chars, font, attributes, frc);
return;
}
}
standardInit(text, chars, frc);
}
/**
* Creates a {@code TextLayout} from a {@link TextLine} and
* some paragraph data. This method is used by {@link TextMeasurer}.
* @param textLine the line measurement attributes to apply to the
* the resulting {@code TextLayout}
* @param baseline the baseline of the text
* @param baselineOffsets the baseline offsets for this
* {@code TextLayout}. This should already be normalized to
* {@code baseline}
* @param justifyRatio {@code 0} if the {@code TextLayout}
* cannot be justified; {@code 1} otherwise.
*/
TextLayout(TextLine textLine,
byte baseline,
float[] baselineOffsets,
float justifyRatio) {
this.characterCount = textLine.characterCount();
this.baseline = baseline;
this.baselineOffsets = baselineOffsets;
this.textLine = textLine;
this.justifyRatio = justifyRatio;
}
/**
* Initialize the paragraph-specific data.
*/
private void paragraphInit(byte aBaseline, CoreMetrics lm,
Map<? extends Attribute, ?> paragraphAttrs,
char[] text) {
baseline = aBaseline;
// normalize to current baseline
baselineOffsets = TextLine.getNormalizedOffsets(lm.baselineOffsets, baseline);
justifyRatio = AttributeValues.getJustification(paragraphAttrs);
NumericShaper shaper = AttributeValues.getNumericShaping(paragraphAttrs);
if (shaper != null) {
shaper.shape(text, 0, text.length);
}
}
/*
* the fast init generates a single glyph set. This requires:
* all one style
* all renderable by one font (ie no embedded graphics)
* all on one baseline
*/
private void fastInit(char[] chars, Font font,
Map<? extends Attribute, ?> attrs,
FontRenderContext frc) {
// Object vf = attrs.get(TextAttribute.ORIENTATION);
// isVerticalLine = TextAttribute.ORIENTATION_VERTICAL.equals(vf);
isVerticalLine = false;
LineMetrics lm = font.getLineMetrics(chars, 0, chars.length, frc);
CoreMetrics cm = CoreMetrics.get(lm);
byte glyphBaseline = (byte) cm.baselineIndex;
if (attrs == null) {
baseline = glyphBaseline;
baselineOffsets = cm.baselineOffsets;
justifyRatio = 1.0f;
} else {
paragraphInit(glyphBaseline, cm, attrs, chars);
}
characterCount = chars.length;
textLine = TextLine.fastCreateTextLine(frc, chars, font, cm, attrs);
}
/*
* the standard init generates multiple glyph sets based on style,
* renderable, and baseline runs.
* @param chars the text in the iterator, extracted into a char array
*/
private void standardInit(AttributedCharacterIterator text, char[] chars, FontRenderContext frc) {
characterCount = chars.length;
// set paragraph attributes
{
// If there's an embedded graphic at the start of the
// paragraph, look for the first non-graphic character
// and use it and its font to initialize the paragraph.
// If not, use the first graphic to initialize.
Map<? extends Attribute, ?> paragraphAttrs = text.getAttributes();
boolean haveFont = TextLine.advanceToFirstFont(text);
if (haveFont) {
Font defaultFont = TextLine.getFontAtCurrentPos(text);
int charsStart = text.getIndex() - text.getBeginIndex();
LineMetrics lm = defaultFont.getLineMetrics(chars, charsStart, charsStart+1, frc);
CoreMetrics cm = CoreMetrics.get(lm);
paragraphInit((byte)cm.baselineIndex, cm, paragraphAttrs, chars);
}
else {
// hmmm what to do here? Just try to supply reasonable
// values I guess.
GraphicAttribute graphic = (GraphicAttribute)
paragraphAttrs.get(TextAttribute.CHAR_REPLACEMENT);
byte defaultBaseline = getBaselineFromGraphic(graphic);
CoreMetrics cm = GraphicComponent.createCoreMetrics(graphic);
paragraphInit(defaultBaseline, cm, paragraphAttrs, chars);
}
}
textLine = TextLine.standardCreateTextLine(frc, text, chars, baselineOffsets);
}
/*
* A utility to rebuild the ascent/descent/leading/advance cache.
* You'll need to call this if you clone and mutate (like justification,
* editing methods do)
*/
private void ensureCache() {
if (!cacheIsValid) {
buildCache();
}
}
private void buildCache() {
lineMetrics = textLine.getMetrics();
// compute visibleAdvance
if (textLine.isDirectionLTR()) {
int lastNonSpace = characterCount-1;
while (lastNonSpace != -1) {
int logIndex = textLine.visualToLogical(lastNonSpace);
if (!textLine.isCharSpace(logIndex)) {
break;
}
else {
--lastNonSpace;
}
}
if (lastNonSpace == characterCount-1) {
visibleAdvance = lineMetrics.advance;
}
else if (lastNonSpace == -1) {
visibleAdvance = 0;
}
else {
int logIndex = textLine.visualToLogical(lastNonSpace);
visibleAdvance = textLine.getCharLinePosition(logIndex)
+ textLine.getCharAdvance(logIndex);
}
}
else {
int leftmostNonSpace = 0;
while (leftmostNonSpace != characterCount) {
int logIndex = textLine.visualToLogical(leftmostNonSpace);
if (!textLine.isCharSpace(logIndex)) {
break;
}
else {
++leftmostNonSpace;
}
}
if (leftmostNonSpace == characterCount) {
visibleAdvance = 0;
}
else if (leftmostNonSpace == 0) {
visibleAdvance = lineMetrics.advance;
}
else {
int logIndex = textLine.visualToLogical(leftmostNonSpace);
float pos = textLine.getCharLinePosition(logIndex);
visibleAdvance = lineMetrics.advance - pos;
}
}
// naturalBounds, boundsRect will be generated on demand
naturalBounds = null;
boundsRect = null;
cacheIsValid = true;
}
/**
* The 'natural bounds' encloses all the carets the layout can draw.
*
*/
private Rectangle2D getNaturalBounds() {
ensureCache();
if (naturalBounds == null) {
naturalBounds = textLine.getItalicBounds();
}
return naturalBounds;
}
/**
* Creates a copy of this {@code TextLayout}.
*/
protected Object clone() {
/*
* !!! I think this is safe. Once created, nothing mutates the
* glyphvectors or arrays. But we need to make sure.
* {jbr} actually, that's not quite true. The justification code
* mutates after cloning. It doesn't actually change the glyphvectors
* (that's impossible) but it replaces them with justified sets. This
* is a problem for GlyphIterator creation, since new GlyphIterators
* are created by cloning a prototype. If the prototype has outdated
* glyphvectors, so will the new ones. A partial solution is to set the
* prototypical GlyphIterator to null when the glyphvectors change. If
* you forget this one time, you're hosed.
*/
try {
return super.clone();
}
catch (CloneNotSupportedException e) {
throw new InternalError(e);
}
}
/*
* Utility to throw an exception if an invalid TextHitInfo is passed
* as a parameter. Avoids code duplication.
*/
private void checkTextHit(TextHitInfo hit) {
if (hit == null) {
throw new IllegalArgumentException("TextHitInfo is null.");
}
if (hit.getInsertionIndex() < 0 ||
hit.getInsertionIndex() > characterCount) {
throw new IllegalArgumentException("TextHitInfo is out of range");
}
}
/**
* Creates a copy of this {@code TextLayout} justified to the
* specified width.
* <p>
* If this {@code TextLayout} has already been justified, an
* exception is thrown. If this {@code TextLayout} object's
* justification ratio is zero, a {@code TextLayout} identical
* to this {@code TextLayout} is returned.
* @param justificationWidth the width to use when justifying the line.
* For best results, it should not be too different from the current
* advance of the line.
* @return a {@code TextLayout} justified to the specified width.
* @throws Error if this layout has already been justified, an Error is
* thrown.
*/
public TextLayout getJustifiedLayout(float justificationWidth) {
if (justificationWidth <= 0) {
throw new IllegalArgumentException("justificationWidth <= 0 passed to TextLayout.getJustifiedLayout()");
}
if (justifyRatio == ALREADY_JUSTIFIED) {
throw new Error("Can't justify again.");
}
ensureCache(); // make sure textLine is not null
// default justification range to exclude trailing logical whitespace
int limit = characterCount;
while (limit > 0 && textLine.isCharWhitespace(limit-1)) {
--limit;
}
TextLine newLine = textLine.getJustifiedLine(justificationWidth, justifyRatio, 0, limit);
if (newLine != null) {
return new TextLayout(newLine, baseline, baselineOffsets, ALREADY_JUSTIFIED);
}
return this;
}
/**
* Justify this layout. Overridden by subclassers to control justification
* (if there were subclassers, that is...)
*
* The layout will only justify if the paragraph attributes (from the
* source text, possibly defaulted by the layout attributes) indicate a
* non-zero justification ratio. The text will be justified to the
* indicated width. The current implementation also adjusts hanging
* punctuation and trailing whitespace to overhang the justification width.
* Once justified, the layout may not be rejustified.
* <p>
* Some code may rely on immutability of layouts. Subclassers should not
* call this directly, but instead should call getJustifiedLayout, which
* will call this method on a clone of this layout, preserving
* the original.
*
* @param justificationWidth the width to use when justifying the line.
* For best results, it should not be too different from the current
* advance of the line.
* @see #getJustifiedLayout(float)
*/
protected void handleJustify(float justificationWidth) {
// never called
}
/**
* Returns the baseline for this {@code TextLayout}.
* The baseline is one of the values defined in {@code Font},
* which are roman, centered and hanging. Ascent and descent are
* relative to this baseline. The {@code baselineOffsets}
* are also relative to this baseline.
* @return the baseline of this {@code TextLayout}.
* @see #getBaselineOffsets()
* @see Font
*/
public byte getBaseline() {
return baseline;
}
/**
* Returns the offsets array for the baselines used for this
* {@code TextLayout}.
* <p>
* The array is indexed by one of the values defined in
* {@code Font}, which are roman, centered and hanging. The
* values are relative to this {@code TextLayout} object's
* baseline, so that {@code getBaselineOffsets[getBaseline()] == 0}.
* Offsets are added to the position of the {@code TextLayout}
* object's baseline to get the position for the new baseline.
* @return the offsets array containing the baselines used for this
* {@code TextLayout}.
* @see #getBaseline()
* @see Font
*/
public float[] getBaselineOffsets() {
float[] offsets = new float[baselineOffsets.length];
System.arraycopy(baselineOffsets, 0, offsets, 0, offsets.length);
return offsets;
}
/**
* Returns the advance of this {@code TextLayout}.
* The advance is the distance from the origin to the advance of the
* rightmost (bottommost) character. This is in baseline-relative
* coordinates.
* @return the advance of this {@code TextLayout}.
*/
public float getAdvance() {
ensureCache();
return lineMetrics.advance;
}
/**
* Returns the advance of this {@code TextLayout}, minus trailing
* whitespace. This is in baseline-relative coordinates.
* @return the advance of this {@code TextLayout} without the
* trailing whitespace.
* @see #getAdvance()
*/
public float getVisibleAdvance() {
ensureCache();
return visibleAdvance;
}
/**
* Returns the ascent of this {@code TextLayout}.
* The ascent is the distance from the top (right) of the
* {@code TextLayout} to the baseline. It is always either
* positive or zero. The ascent is sufficient to
* accommodate superscripted text and is the maximum of the sum of the
* ascent, offset, and baseline of each glyph. The ascent is
* the maximum ascent from the baseline of all the text in the
* TextLayout. It is in baseline-relative coordinates.
* @return the ascent of this {@code TextLayout}.
*/
public float getAscent() {
ensureCache();
return lineMetrics.ascent;
}
/**
* Returns the descent of this {@code TextLayout}.
* The descent is the distance from the baseline to the bottom (left) of
* the {@code TextLayout}. It is always either positive or zero.
* The descent is sufficient to accommodate subscripted text and is the
* maximum of the sum of the descent, offset, and baseline of each glyph.
* This is the maximum descent from the baseline of all the text in
* the TextLayout. It is in baseline-relative coordinates.
* @return the descent of this {@code TextLayout}.
*/
public float getDescent() {
ensureCache();
return lineMetrics.descent;
}
/**
* Returns the leading of the {@code TextLayout}.
* The leading is the suggested interline spacing for this
* {@code TextLayout}. This is in baseline-relative
* coordinates.
* <p>
* The leading is computed from the leading, descent, and baseline
* of all glyphvectors in the {@code TextLayout}. The algorithm
* is roughly as follows:
* <blockquote><pre>
* maxD = 0;
* maxDL = 0;
* for (GlyphVector g in all glyphvectors) {
* maxD = max(maxD, g.getDescent() + offsets[g.getBaseline()]);
* maxDL = max(maxDL, g.getDescent() + g.getLeading() +
* offsets[g.getBaseline()]);
* }
* return maxDL - maxD;
* </pre></blockquote>
* @return the leading of this {@code TextLayout}.
*/
public float getLeading() {
ensureCache();
return lineMetrics.leading;
}
/**
* Returns the bounds of this {@code TextLayout}.
* The bounds are in standard coordinates.
* <p>Due to rasterization effects, this bounds might not enclose all of the
* pixels rendered by the TextLayout.</p>
* It might not coincide exactly with the ascent, descent,
* origin or advance of the {@code TextLayout}.
* @return a {@link Rectangle2D} that is the bounds of this
* {@code TextLayout}.
*/
public Rectangle2D getBounds() {
ensureCache();
if (boundsRect == null) {
Rectangle2D vb = textLine.getVisualBounds();
if (dx != 0 || dy != 0) {
vb.setRect(vb.getX() - dx,
vb.getY() - dy,
vb.getWidth(),
vb.getHeight());
}
boundsRect = vb;
}
Rectangle2D bounds = new Rectangle2D.Float();
bounds.setRect(boundsRect);
return bounds;
}
/**
* Returns the pixel bounds of this {@code TextLayout} when
* rendered in a graphics with the given
* {@code FontRenderContext} at the given location. The
* graphics render context need not be the same as the
* {@code FontRenderContext} used to create this
* {@code TextLayout}, and can be null. If it is null, the
* {@code FontRenderContext} of this {@code TextLayout}
* is used.
* @param frc the {@code FontRenderContext} of the {@code Graphics}.
* @param x the x-coordinate at which to render this {@code TextLayout}.
* @param y the y-coordinate at which to render this {@code TextLayout}.
* @return a {@code Rectangle} bounding the pixels that would be affected.
* @see GlyphVector#getPixelBounds
* @since 1.6
*/
public Rectangle getPixelBounds(FontRenderContext frc, float x, float y) {
return textLine.getPixelBounds(frc, x, y);
}
/**
* Returns {@code true} if this {@code TextLayout} has
* a left-to-right base direction or {@code false} if it has
* a right-to-left base direction. The {@code TextLayout}
* has a base direction of either left-to-right (LTR) or
* right-to-left (RTL). The base direction is independent of the
* actual direction of text on the line, which may be either LTR,
* RTL, or mixed. Left-to-right layouts by default should position
* flush left. If the layout is on a tabbed line, the
* tabs run left to right, so that logically successive layouts position
* left to right. The opposite is true for RTL layouts. By default they
* should position flush left, and tabs run right-to-left.
* @return {@code true} if the base direction of this
* {@code TextLayout} is left-to-right; {@code false}
* otherwise.
*/
public boolean isLeftToRight() {
return textLine.isDirectionLTR();
}
/**
* Returns {@code true} if this {@code TextLayout} is vertical.
* @return {@code true} if this {@code TextLayout} is vertical;
* {@code false} otherwise.
*/
public boolean isVertical() {
return isVerticalLine;
}
/**
* Returns the number of characters represented by this
* {@code TextLayout}.
* @return the number of characters in this {@code TextLayout}.
*/
public int getCharacterCount() {
return characterCount;
}
/*
* carets and hit testing
*
* Positions on a text line are represented by instances of TextHitInfo.
* Any TextHitInfo with characterOffset between 0 and characterCount-1,
* inclusive, represents a valid position on the line. Additionally,
* [-1, trailing] and [characterCount, leading] are valid positions, and
* represent positions at the logical start and end of the line,
* respectively.
*
* The characterOffsets in TextHitInfo's used and returned by TextLayout
* are relative to the beginning of the text layout, not necessarily to
* the beginning of the text storage the client is using.
*
*
* Every valid TextHitInfo has either one or two carets associated with it.
* A caret is a visual location in the TextLayout indicating where text at
* the TextHitInfo will be displayed on screen. If a TextHitInfo
* represents a location on a directional boundary, then there are two
* possible visible positions for newly inserted text. Consider the
* following example, in which capital letters indicate right-to-left text,
* and the overall line direction is left-to-right:
*
* Text Storage: [ a, b, C, D, E, f ]
* Display: a b E D C f
*
* The text hit info (1, t) represents the trailing side of 'b'. If 'q',
* a left-to-right character is inserted into the text storage at this
* location, it will be displayed between the 'b' and the 'E':
*
* Text Storage: [ a, b, q, C, D, E, f ]
* Display: a b q E D C f
*
* However, if a 'W', which is right-to-left, is inserted into the storage
* after 'b', the storage and display will be:
*
* Text Storage: [ a, b, W, C, D, E, f ]
* Display: a b E D C W f
*
* So, for the original text storage, two carets should be displayed for
* location (1, t): one visually between 'b' and 'E' and one visually
* between 'C' and 'f'.
*
*
* When two carets are displayed for a TextHitInfo, one caret is the
* 'strong' caret and the other is the 'weak' caret. The strong caret
* indicates where an inserted character will be displayed when that
* character's direction is the same as the direction of the TextLayout.
* The weak caret shows where an character inserted character will be
* displayed when the character's direction is opposite that of the
* TextLayout.
*
*
* Clients should not be overly concerned with the details of correct
* caret display. TextLayout.getCaretShapes(TextHitInfo) will return an
* array of two paths representing where carets should be displayed.
* The first path in the array is the strong caret; the second element,
* if non-null, is the weak caret. If the second element is null,
* then there is no weak caret for the given TextHitInfo.
*
*
* Since text can be visually reordered, logically consecutive
* TextHitInfo's may not be visually consecutive. One implication of this
* is that a client cannot tell from inspecting a TextHitInfo whether the
* hit represents the first (or last) caret in the layout. Clients
* can call getVisualOtherHit(); if the visual companion is
* (-1, TRAILING) or (characterCount, LEADING), then the hit is at the
* first (last) caret position in the layout.
*/
private float[] getCaretInfo(int caret,
Rectangle2D bounds,
float[] info) {
float top1X, top2X;
float bottom1X, bottom2X;
if (caret == 0 || caret == characterCount) {
float pos;
int logIndex;
if (caret == characterCount) {
logIndex = textLine.visualToLogical(characterCount-1);
pos = textLine.getCharLinePosition(logIndex)
+ textLine.getCharAdvance(logIndex);
}
else {
logIndex = textLine.visualToLogical(caret);
pos = textLine.getCharLinePosition(logIndex);
}
float angle = textLine.getCharAngle(logIndex);
float shift = textLine.getCharShift(logIndex);
pos += angle * shift;
top1X = top2X = pos + angle*textLine.getCharAscent(logIndex);
bottom1X = bottom2X = pos - angle*textLine.getCharDescent(logIndex);
}
else {
{
int logIndex = textLine.visualToLogical(caret-1);
float angle1 = textLine.getCharAngle(logIndex);
float pos1 = textLine.getCharLinePosition(logIndex)
+ textLine.getCharAdvance(logIndex);
if (angle1 != 0) {
pos1 += angle1 * textLine.getCharShift(logIndex);
top1X = pos1 + angle1*textLine.getCharAscent(logIndex);
bottom1X = pos1 - angle1*textLine.getCharDescent(logIndex);
}
else {
top1X = bottom1X = pos1;
}
}
{
int logIndex = textLine.visualToLogical(caret);
float angle2 = textLine.getCharAngle(logIndex);
float pos2 = textLine.getCharLinePosition(logIndex);
if (angle2 != 0) {
pos2 += angle2*textLine.getCharShift(logIndex);
top2X = pos2 + angle2*textLine.getCharAscent(logIndex);
bottom2X = pos2 - angle2*textLine.getCharDescent(logIndex);
}
else {
top2X = bottom2X = pos2;
}
}
}
float topX = (top1X + top2X) / 2;
float bottomX = (bottom1X + bottom2X) / 2;
if (info == null) {
info = new float[2];
}
if (isVerticalLine) {
info[1] = (float) ((topX - bottomX) / bounds.getWidth());
info[0] = (float) (topX + (info[1]*bounds.getX()));
}
else {
info[1] = (float) ((topX - bottomX) / bounds.getHeight());
info[0] = (float) (bottomX + (info[1]*bounds.getMaxY()));
}
return info;
}
/**
* Returns information about the caret corresponding to {@code hit}.
* The first element of the array is the intersection of the caret with
* the baseline, as a distance along the baseline. The second element
* of the array is the inverse slope (run/rise) of the caret, measured
* with respect to the baseline at that point.
* <p>
* This method is meant for informational use. To display carets, it
* is better to use {@code getCaretShapes}.
* @param hit a hit on a character in this {@code TextLayout}
* @param bounds the bounds to which the caret info is constructed.
* The bounds is in baseline-relative coordinates.
* @return a two-element array containing the position and slope of
* the caret. The returned caret info is in baseline-relative coordinates.
* @see #getCaretShapes(int, Rectangle2D, TextLayout.CaretPolicy)
* @see Font#getItalicAngle
*/
public float[] getCaretInfo(TextHitInfo hit, Rectangle2D bounds) {
ensureCache();
checkTextHit(hit);
return getCaretInfoTestInternal(hit, bounds);
}
// this version provides extra info in the float array
// the first two values are as above
// the next four values are the endpoints of the caret, as computed
// using the hit character's offset (baseline + ssoffset) and
// natural ascent and descent.
// these values are trimmed to the bounds where required to fit,
// but otherwise independent of it.
private float[] getCaretInfoTestInternal(TextHitInfo hit, Rectangle2D bounds) {
ensureCache();
checkTextHit(hit);
float[] info = new float[6];
// get old data first
getCaretInfo(hitToCaret(hit), bounds, info);
// then add our new data
double iangle, ixbase, p1x, p1y, p2x, p2y;
int charix = hit.getCharIndex();
boolean lead = hit.isLeadingEdge();
boolean ltr = textLine.isDirectionLTR();
boolean horiz = !isVertical();
if (charix == -1 || charix == characterCount) {
// !!! note: want non-shifted, baseline ascent and descent here!
// TextLine should return appropriate line metrics object for these values
TextLineMetrics m = textLine.getMetrics();
boolean low = ltr == (charix == -1);
iangle = 0;
if (horiz) {
p1x = p2x = low ? 0 : m.advance;
p1y = -m.ascent;
p2y = m.descent;
} else {
p1y = p2y = low ? 0 : m.advance;
p1x = m.descent;
p2x = m.ascent;
}
} else {
CoreMetrics thiscm = textLine.getCoreMetricsAt(charix);
iangle = thiscm.italicAngle;
ixbase = textLine.getCharLinePosition(charix, lead);
if (thiscm.baselineIndex < 0) {
// this is a graphic, no italics, use entire line height for caret
TextLineMetrics m = textLine.getMetrics();
if (horiz) {
p1x = p2x = ixbase;
if (thiscm.baselineIndex == GraphicAttribute.TOP_ALIGNMENT) {
p1y = -m.ascent;
p2y = p1y + thiscm.height;
} else {
p2y = m.descent;
p1y = p2y - thiscm.height;
}
} else {
p1y = p2y = ixbase;
p1x = m.descent;
p2x = m.ascent;
// !!! top/bottom adjustment not implemented for vertical
}
} else {
float bo = baselineOffsets[thiscm.baselineIndex];
if (horiz) {
ixbase += iangle * thiscm.ssOffset;
p1x = ixbase + iangle * thiscm.ascent;
p2x = ixbase - iangle * thiscm.descent;
p1y = bo - thiscm.ascent;
p2y = bo + thiscm.descent;
} else {
ixbase -= iangle * thiscm.ssOffset;
p1y = ixbase + iangle * thiscm.ascent;
p2y = ixbase - iangle * thiscm.descent;
p1x = bo + thiscm.ascent;
p2x = bo + thiscm.descent;
}
}
}
info[2] = (float)p1x;
info[3] = (float)p1y;
info[4] = (float)p2x;
info[5] = (float)p2y;
return info;
}
/**
* Returns information about the caret corresponding to {@code hit}.
* This method is a convenience overload of {@code getCaretInfo} and
* uses the natural bounds of this {@code TextLayout}.
* @param hit a hit on a character in this {@code TextLayout}
* @return the information about a caret corresponding to a hit. The
* returned caret info is in baseline-relative coordinates.
*/
public float[] getCaretInfo(TextHitInfo hit) {
return getCaretInfo(hit, getNaturalBounds());
}
/**
* Returns a caret index corresponding to {@code hit}.
* Carets are numbered from left to right (top to bottom) starting from
* zero. This always places carets next to the character hit, on the
* indicated side of the character.
* @param hit a hit on a character in this {@code TextLayout}
* @return a caret index corresponding to the specified hit.
*/
private int hitToCaret(TextHitInfo hit) {
int hitIndex = hit.getCharIndex();
if (hitIndex < 0) {
return textLine.isDirectionLTR() ? 0 : characterCount;
} else if (hitIndex >= characterCount) {
return textLine.isDirectionLTR() ? characterCount : 0;
}
int visIndex = textLine.logicalToVisual(hitIndex);
if (hit.isLeadingEdge() != textLine.isCharLTR(hitIndex)) {
++visIndex;
}
return visIndex;
}
/**
* Given a caret index, return a hit whose caret is at the index.
* The hit is NOT guaranteed to be strong!!!
*
* @param caret a caret index.
* @return a hit on this layout whose strong caret is at the requested
* index.
*/
private TextHitInfo caretToHit(int caret) {
if (caret == 0 || caret == characterCount) {
if ((caret == characterCount) == textLine.isDirectionLTR()) {
return TextHitInfo.leading(characterCount);
}
else {
return TextHitInfo.trailing(-1);
}
}
else {
int charIndex = textLine.visualToLogical(caret);
boolean leading = textLine.isCharLTR(charIndex);
return leading? TextHitInfo.leading(charIndex)
: TextHitInfo.trailing(charIndex);
}
}
private boolean caretIsValid(int caret) {
if (caret == characterCount || caret == 0) {
return true;
}
int offset = textLine.visualToLogical(caret);
if (!textLine.isCharLTR(offset)) {
offset = textLine.visualToLogical(caret-1);
if (textLine.isCharLTR(offset)) {
return true;
}
}
// At this point, the leading edge of the character
// at offset is at the given caret.
return textLine.caretAtOffsetIsValid(offset);
}
/**
* Returns the hit for the next caret to the right (bottom); if there
* is no such hit, returns {@code null}.
* If the hit character index is out of bounds, an
* {@link IllegalArgumentException} is thrown.
* @param hit a hit on a character in this layout
* @return a hit whose caret appears at the next position to the
* right (bottom) of the caret of the provided hit or {@code null}.
*/
public TextHitInfo getNextRightHit(TextHitInfo hit) {
ensureCache();
checkTextHit(hit);
int caret = hitToCaret(hit);
if (caret == characterCount) {
return null;
}
do {
++caret;
} while (!caretIsValid(caret));
return caretToHit(caret);
}
/**
* Returns the hit for the next caret to the right (bottom); if no
* such hit, returns {@code null}. The hit is to the right of
* the strong caret at the specified offset, as determined by the
* specified policy.
* The returned hit is the stronger of the two possible
* hits, as determined by the specified policy.
* @param offset an insertion offset in this {@code TextLayout}.
* Cannot be less than 0 or greater than this {@code TextLayout}
* object's character count.
* @param policy the policy used to select the strong caret
* @return a hit whose caret appears at the next position to the
* right (bottom) of the caret of the provided hit, or {@code null}.
*/
public TextHitInfo getNextRightHit(int offset, CaretPolicy policy) {
if (offset < 0 || offset > characterCount) {
throw new IllegalArgumentException("Offset out of bounds in TextLayout.getNextRightHit()");
}
if (policy == null) {
throw new IllegalArgumentException("Null CaretPolicy passed to TextLayout.getNextRightHit()");
}
TextHitInfo hit1 = TextHitInfo.afterOffset(offset);
TextHitInfo hit2 = hit1.getOtherHit();
TextHitInfo nextHit = getNextRightHit(policy.getStrongCaret(hit1, hit2, this));
if (nextHit != null) {
TextHitInfo otherHit = getVisualOtherHit(nextHit);
return policy.getStrongCaret(otherHit, nextHit, this);
}
else {
return null;
}
}
/**
* Returns the hit for the next caret to the right (bottom); if no
* such hit, returns {@code null}. The hit is to the right of
* the strong caret at the specified offset, as determined by the
* default policy.
* The returned hit is the stronger of the two possible
* hits, as determined by the default policy.
* @param offset an insertion offset in this {@code TextLayout}.
* Cannot be less than 0 or greater than the {@code TextLayout}
* object's character count.
* @return a hit whose caret appears at the next position to the
* right (bottom) of the caret of the provided hit, or {@code null}.
*/
public TextHitInfo getNextRightHit(int offset) {
return getNextRightHit(offset, DEFAULT_CARET_POLICY);
}
/**
* Returns the hit for the next caret to the left (top); if no such
* hit, returns {@code null}.
* If the hit character index is out of bounds, an
* {@code IllegalArgumentException} is thrown.
* @param hit a hit on a character in this {@code TextLayout}.
* @return a hit whose caret appears at the next position to the
* left (top) of the caret of the provided hit, or {@code null}.
*/
public TextHitInfo getNextLeftHit(TextHitInfo hit) {
ensureCache();
checkTextHit(hit);
int caret = hitToCaret(hit);
if (caret == 0) {
return null;
}
do {
--caret;
} while(!caretIsValid(caret));
return caretToHit(caret);
}
/**
* Returns the hit for the next caret to the left (top); if no
* such hit, returns {@code null}. The hit is to the left of
* the strong caret at the specified offset, as determined by the
* specified policy.
* The returned hit is the stronger of the two possible
* hits, as determined by the specified policy.
* @param offset an insertion offset in this {@code TextLayout}.
* Cannot be less than 0 or greater than this {@code TextLayout}
* object's character count.
* @param policy the policy used to select the strong caret
* @return a hit whose caret appears at the next position to the
* left (top) of the caret of the provided hit, or {@code null}.
*/
public TextHitInfo getNextLeftHit(int offset, CaretPolicy policy) {
if (policy == null) {
throw new IllegalArgumentException("Null CaretPolicy passed to TextLayout.getNextLeftHit()");
}
if (offset < 0 || offset > characterCount) {
throw new IllegalArgumentException("Offset out of bounds in TextLayout.getNextLeftHit()");
}
TextHitInfo hit1 = TextHitInfo.afterOffset(offset);
TextHitInfo hit2 = hit1.getOtherHit();
TextHitInfo nextHit = getNextLeftHit(policy.getStrongCaret(hit1, hit2, this));
if (nextHit != null) {
TextHitInfo otherHit = getVisualOtherHit(nextHit);
return policy.getStrongCaret(otherHit, nextHit, this);
}
else {
return null;
}
}
/**
* Returns the hit for the next caret to the left (top); if no
* such hit, returns {@code null}. The hit is to the left of
* the strong caret at the specified offset, as determined by the
* default policy.
* The returned hit is the stronger of the two possible
* hits, as determined by the default policy.
* @param offset an insertion offset in this {@code TextLayout}.
* Cannot be less than 0 or greater than this {@code TextLayout}
* object's character count.
* @return a hit whose caret appears at the next position to the
* left (top) of the caret of the provided hit, or {@code null}.
*/
public TextHitInfo getNextLeftHit(int offset) {
return getNextLeftHit(offset, DEFAULT_CARET_POLICY);
}
/**
* Returns the hit on the opposite side of the specified hit's caret.
* @param hit the specified hit
* @return a hit that is on the opposite side of the specified hit's
* caret.
*/
public TextHitInfo getVisualOtherHit(TextHitInfo hit) {
ensureCache();
checkTextHit(hit);
int hitCharIndex = hit.getCharIndex();
int charIndex;
boolean leading;
if (hitCharIndex == -1 || hitCharIndex == characterCount) {
int visIndex;
if (textLine.isDirectionLTR() == (hitCharIndex == -1)) {
visIndex = 0;
}
else {
visIndex = characterCount-1;
}
charIndex = textLine.visualToLogical(visIndex);
if (textLine.isDirectionLTR() == (hitCharIndex == -1)) {
// at left end
leading = textLine.isCharLTR(charIndex);
}
else {
// at right end
leading = !textLine.isCharLTR(charIndex);
}
}
else {
int visIndex = textLine.logicalToVisual(hitCharIndex);
boolean movedToRight;
if (textLine.isCharLTR(hitCharIndex) == hit.isLeadingEdge()) {
--visIndex;
movedToRight = false;
}
else {
++visIndex;
movedToRight = true;
}
if (visIndex > -1 && visIndex < characterCount) {
charIndex = textLine.visualToLogical(visIndex);
leading = movedToRight == textLine.isCharLTR(charIndex);
}
else {
charIndex =
(movedToRight == textLine.isDirectionLTR())? characterCount : -1;
leading = charIndex == characterCount;
}
}
return leading? TextHitInfo.leading(charIndex) :
TextHitInfo.trailing(charIndex);
}
private double[] getCaretPath(TextHitInfo hit, Rectangle2D bounds) {
float[] info = getCaretInfo(hit, bounds);
return new double[] { info[2], info[3], info[4], info[5] };
}
/**
* Return an array of four floats corresponding the endpoints of the caret
* x0, y0, x1, y1.
*
* This creates a line along the slope of the caret intersecting the
* baseline at the caret
* position, and extending from ascent above the baseline to descent below
* it.
*/
private double[] getCaretPath(int caret, Rectangle2D bounds,
boolean clipToBounds) {
float[] info = getCaretInfo(caret, bounds, null);
double pos = info[0];
double slope = info[1];
double x0, y0, x1, y1;
double x2 = -3141.59, y2 = -2.7; // values are there to make compiler happy
double left = bounds.getX();
double right = left + bounds.getWidth();
double top = bounds.getY();
double bottom = top + bounds.getHeight();
boolean threePoints = false;
if (isVerticalLine) {
if (slope >= 0) {
x0 = left;
x1 = right;
}
else {
x1 = left;
x0 = right;
}
y0 = pos + x0 * slope;
y1 = pos + x1 * slope;
// y0 <= y1, always
if (clipToBounds) {
if (y0 < top) {
if (slope <= 0 || y1 <= top) {
y0 = y1 = top;
}
else {
threePoints = true;
y0 = top;
y2 = top;
x2 = x1 + (top-y1)/slope;
if (y1 > bottom) {
y1 = bottom;
}
}
}
else if (y1 > bottom) {
if (slope >= 0 || y0 >= bottom) {
y0 = y1 = bottom;
}
else {
threePoints = true;
y1 = bottom;
y2 = bottom;
x2 = x0 + (bottom-x1)/slope;
}
}
}
}
else {
if (slope >= 0) {
y0 = bottom;
y1 = top;
}
else {
y1 = bottom;
y0 = top;
}
x0 = pos - y0 * slope;
x1 = pos - y1 * slope;
// x0 <= x1, always
if (clipToBounds) {
if (x0 < left) {
if (slope <= 0 || x1 <= left) {
x0 = x1 = left;
}
else {
threePoints = true;
x0 = left;
x2 = left;
y2 = y1 - (left-x1)/slope;
if (x1 > right) {
x1 = right;
}
}
}
else if (x1 > right) {
if (slope >= 0 || x0 >= right) {
x0 = x1 = right;
}
else {
threePoints = true;
x1 = right;
x2 = right;
y2 = y0 - (right-x0)/slope;
}
}
}
}
return threePoints?
new double[] { x0, y0, x2, y2, x1, y1 } :
new double[] { x0, y0, x1, y1 };
}
private static GeneralPath pathToShape(double[] path, boolean close, LayoutPathImpl lp) {
GeneralPath result = new GeneralPath(GeneralPath.WIND_EVEN_ODD, path.length);
result.moveTo((float)path[0], (float)path[1]);
for (int i = 2; i < path.length; i += 2) {
result.lineTo((float)path[i], (float)path[i+1]);
}
if (close) {
result.closePath();
}
if (lp != null) {
result = (GeneralPath)lp.mapShape(result);
}
return result;
}
/**
* Returns a {@link Shape} representing the caret at the specified
* hit inside the specified bounds.
* @param hit the hit at which to generate the caret
* @param bounds the bounds of the {@code TextLayout} to use
* in generating the caret. The bounds is in baseline-relative
* coordinates.
* @return a {@code Shape} representing the caret. The returned
* shape is in standard coordinates.
*/
public Shape getCaretShape(TextHitInfo hit, Rectangle2D bounds) {
ensureCache();
checkTextHit(hit);
if (bounds == null) {
throw new IllegalArgumentException("Null Rectangle2D passed to TextLayout.getCaret()");
}
return pathToShape(getCaretPath(hit, bounds), false, textLine.getLayoutPath());
}
/**
* Returns a {@code Shape} representing the caret at the specified
* hit inside the natural bounds of this {@code TextLayout}.
* @param hit the hit at which to generate the caret
* @return a {@code Shape} representing the caret. The returned
* shape is in standard coordinates.
*/
public Shape getCaretShape(TextHitInfo hit) {
return getCaretShape(hit, getNaturalBounds());
}
/**
* Return the "stronger" of the TextHitInfos. The TextHitInfos
* should be logical or visual counterparts. They are not
* checked for validity.
*/
private TextHitInfo getStrongHit(TextHitInfo hit1, TextHitInfo hit2) {
// right now we're using the following rule for strong hits:
// A hit on a character with a lower level
// is stronger than one on a character with a higher level.
// If this rule ties, the hit on the leading edge of a character wins.
// If THIS rule ties, hit1 wins. Both rules shouldn't tie, unless the
// infos aren't counterparts of some sort.
byte hit1Level = getCharacterLevel(hit1.getCharIndex());
byte hit2Level = getCharacterLevel(hit2.getCharIndex());
if (hit1Level == hit2Level) {
if (hit2.isLeadingEdge() && !hit1.isLeadingEdge()) {
return hit2;
}
else {
return hit1;
}
}
else {
return (hit1Level < hit2Level)? hit1 : hit2;
}
}
/**
* Returns the level of the character at {@code index}.
* Indices -1 and {@code characterCount} are assigned the base
* level of this {@code TextLayout}.
* @param index the index of the character from which to get the level
* @return the level of the character at the specified index.
*/
public byte getCharacterLevel(int index) {
// hmm, allow indices at endpoints? For now, yes.
if (index < -1 || index > characterCount) {
throw new IllegalArgumentException("Index is out of range in getCharacterLevel.");
}
ensureCache();
if (index == -1 || index == characterCount) {
return (byte) (textLine.isDirectionLTR()? 0 : 1);
}
return textLine.getCharLevel(index);
}
/**
* Returns two paths corresponding to the strong and weak caret.
* @param offset an offset in this {@code TextLayout}
* @param bounds the bounds to which to extend the carets. The
* bounds is in baseline-relative coordinates.
* @param policy the specified {@code CaretPolicy}
* @return an array of two paths. Element zero is the strong
* caret. If there are two carets, element one is the weak caret,
* otherwise it is {@code null}. The returned shapes
* are in standard coordinates.
*/
public Shape[] getCaretShapes(int offset, Rectangle2D bounds, CaretPolicy policy) {
ensureCache();
if (offset < 0 || offset > characterCount) {
throw new IllegalArgumentException("Offset out of bounds in TextLayout.getCaretShapes()");
}
if (bounds == null) {
throw new IllegalArgumentException("Null Rectangle2D passed to TextLayout.getCaretShapes()");
}
if (policy == null) {
throw new IllegalArgumentException("Null CaretPolicy passed to TextLayout.getCaretShapes()");
}
Shape[] result = new Shape[2];
TextHitInfo hit = TextHitInfo.afterOffset(offset);
int hitCaret = hitToCaret(hit);
LayoutPathImpl lp = textLine.getLayoutPath();
Shape hitShape = pathToShape(getCaretPath(hit, bounds), false, lp);
TextHitInfo otherHit = hit.getOtherHit();
int otherCaret = hitToCaret(otherHit);
if (hitCaret == otherCaret) {
result[0] = hitShape;
}
else { // more than one caret
Shape otherShape = pathToShape(getCaretPath(otherHit, bounds), false, lp);
TextHitInfo strongHit = policy.getStrongCaret(hit, otherHit, this);
boolean hitIsStrong = strongHit.equals(hit);
if (hitIsStrong) {// then other is weak
result[0] = hitShape;
result[1] = otherShape;
}
else {
result[0] = otherShape;
result[1] = hitShape;
}
}
return result;
}
/**
* Returns two paths corresponding to the strong and weak caret.
* This method is a convenience overload of {@code getCaretShapes}
* that uses the default caret policy.
* @param offset an offset in this {@code TextLayout}
* @param bounds the bounds to which to extend the carets. This is
* in baseline-relative coordinates.
* @return two paths corresponding to the strong and weak caret as
* defined by the {@code DEFAULT_CARET_POLICY}. These are
* in standard coordinates.
*/
public Shape[] getCaretShapes(int offset, Rectangle2D bounds) {
// {sfb} parameter checking is done in overloaded version
return getCaretShapes(offset, bounds, DEFAULT_CARET_POLICY);
}
/**
* Returns two paths corresponding to the strong and weak caret.
* This method is a convenience overload of {@code getCaretShapes}
* that uses the default caret policy and this {@code TextLayout}
* object's natural bounds.
* @param offset an offset in this {@code TextLayout}
* @return two paths corresponding to the strong and weak caret as
* defined by the {@code DEFAULT_CARET_POLICY}. These are
* in standard coordinates.
*/
public Shape[] getCaretShapes(int offset) {
// {sfb} parameter checking is done in overloaded version
return getCaretShapes(offset, getNaturalBounds(), DEFAULT_CARET_POLICY);
}
// A utility to return a path enclosing the given path
// Path0 must be left or top of path1
// {jbr} no assumptions about size of path0, path1 anymore.
private GeneralPath boundingShape(double[] path0, double[] path1) {
// Really, we want the path to be a convex hull around all of the
// points in path0 and path1. But we can get by with less than
// that. We do need to prevent the two segments which
// join path0 to path1 from crossing each other. So, if we
// traverse path0 from top to bottom, we'll traverse path1 from
// bottom to top (and vice versa).
GeneralPath result = pathToShape(path0, false, null);
boolean sameDirection;
if (isVerticalLine) {
sameDirection = (path0[1] > path0[path0.length-1]) ==
(path1[1] > path1[path1.length-1]);
}
else {
sameDirection = (path0[0] > path0[path0.length-2]) ==
(path1[0] > path1[path1.length-2]);
}
int start;
int limit;
int increment;
if (sameDirection) {
start = path1.length-2;
limit = -2;
increment = -2;
}
else {
start = 0;
limit = path1.length;
increment = 2;
}
for (int i = start; i != limit; i += increment) {
result.lineTo((float)path1[i], (float)path1[i+1]);
}
result.closePath();
return result;
}
// A utility to convert a pair of carets into a bounding path
// {jbr} Shape is never outside of bounds.
private GeneralPath caretBoundingShape(int caret0,
int caret1,
Rectangle2D bounds) {
if (caret0 > caret1) {
int temp = caret0;
caret0 = caret1;
caret1 = temp;
}
return boundingShape(getCaretPath(caret0, bounds, true),
getCaretPath(caret1, bounds, true));
}
/*
* A utility to return the path bounding the area to the left (top) of the
* layout.
* Shape is never outside of bounds.
*/
private GeneralPath leftShape(Rectangle2D bounds) {
double[] path0;
if (isVerticalLine) {
path0 = new double[] { bounds.getX(), bounds.getY(),
bounds.getX() + bounds.getWidth(),
bounds.getY() };
} else {
path0 = new double[] { bounds.getX(),
bounds.getY() + bounds.getHeight(),
bounds.getX(), bounds.getY() };
}
double[] path1 = getCaretPath(0, bounds, true);
return boundingShape(path0, path1);
}
/*
* A utility to return the path bounding the area to the right (bottom) of
* the layout.
*/
private GeneralPath rightShape(Rectangle2D bounds) {
double[] path1;
if (isVerticalLine) {
path1 = new double[] {
bounds.getX(),
bounds.getY() + bounds.getHeight(),
bounds.getX() + bounds.getWidth(),
bounds.getY() + bounds.getHeight()
};
} else {
path1 = new double[] {
bounds.getX() + bounds.getWidth(),
bounds.getY() + bounds.getHeight(),
bounds.getX() + bounds.getWidth(),
bounds.getY()
};
}
double[] path0 = getCaretPath(characterCount, bounds, true);
return boundingShape(path0, path1);
}
/**
* Returns the logical ranges of text corresponding to a visual selection.
* @param firstEndpoint an endpoint of the visual range
* @param secondEndpoint the other endpoint of the visual range.
* This endpoint can be less than {@code firstEndpoint}.
* @return an array of integers representing start/limit pairs for the
* selected ranges.
* @see #getVisualHighlightShape(TextHitInfo, TextHitInfo, Rectangle2D)
*/
public int[] getLogicalRangesForVisualSelection(TextHitInfo firstEndpoint,
TextHitInfo secondEndpoint) {
ensureCache();
checkTextHit(firstEndpoint);
checkTextHit(secondEndpoint);
// !!! probably want to optimize for all LTR text
boolean[] included = new boolean[characterCount];
int startIndex = hitToCaret(firstEndpoint);
int limitIndex = hitToCaret(secondEndpoint);
if (startIndex > limitIndex) {
int t = startIndex;
startIndex = limitIndex;
limitIndex = t;
}
/*
* now we have the visual indexes of the glyphs at the start and limit
* of the selection range walk through runs marking characters that
* were included in the visual range there is probably a more efficient
* way to do this, but this ought to work, so hey
*/
if (startIndex < limitIndex) {
int visIndex = startIndex;
while (visIndex < limitIndex) {
included[textLine.visualToLogical(visIndex)] = true;
++visIndex;
}
}
/*
* count how many runs we have, ought to be one or two, but perhaps
* things are especially weird
*/
int count = 0;
boolean inrun = false;
for (int i = 0; i < characterCount; i++) {
if (included[i] != inrun) {
inrun = !inrun;
if (inrun) {
count++;
}
}
}
int[] ranges = new int[count * 2];
count = 0;
inrun = false;
for (int i = 0; i < characterCount; i++) {
if (included[i] != inrun) {
ranges[count++] = i;
inrun = !inrun;
}
}
if (inrun) {
ranges[count++] = characterCount;
}
return ranges;
}
/**
* Returns a path enclosing the visual selection in the specified range,
* extended to {@code bounds}.
* <p>
* If the selection includes the leftmost (topmost) position, the selection
* is extended to the left (top) of {@code bounds}. If the
* selection includes the rightmost (bottommost) position, the selection
* is extended to the right (bottom) of the bounds. The height
* (width on vertical lines) of the selection is always extended to
* {@code bounds}.
* <p>
* Although the selection is always contiguous, the logically selected
* text can be discontiguous on lines with mixed-direction text. The
* logical ranges of text selected can be retrieved using
* {@code getLogicalRangesForVisualSelection}. For example,
* consider the text 'ABCdef' where capital letters indicate
* right-to-left text, rendered on a right-to-left line, with a visual
* selection from 0L (the leading edge of 'A') to 3T (the trailing edge
* of 'd'). The text appears as follows, with bold underlined areas
* representing the selection:
* <br><pre>
* d<u><b>efCBA </b></u>
* </pre>
* The logical selection ranges are 0-3, 4-6 (ABC, ef) because the
* visually contiguous text is logically discontiguous. Also note that
* since the rightmost position on the layout (to the right of 'A') is
* selected, the selection is extended to the right of the bounds.
* @param firstEndpoint one end of the visual selection
* @param secondEndpoint the other end of the visual selection
* @param bounds the bounding rectangle to which to extend the selection.
* This is in baseline-relative coordinates.
* @return a {@code Shape} enclosing the selection. This is in
* standard coordinates.
* @see #getLogicalRangesForVisualSelection(TextHitInfo, TextHitInfo)
* @see #getLogicalHighlightShape(int, int, Rectangle2D)
*/
public Shape getVisualHighlightShape(TextHitInfo firstEndpoint,
TextHitInfo secondEndpoint,
Rectangle2D bounds)
{
ensureCache();
checkTextHit(firstEndpoint);
checkTextHit(secondEndpoint);
if(bounds == null) {
throw new IllegalArgumentException("Null Rectangle2D passed to TextLayout.getVisualHighlightShape()");
}
GeneralPath result = new GeneralPath(GeneralPath.WIND_EVEN_ODD);
int firstCaret = hitToCaret(firstEndpoint);
int secondCaret = hitToCaret(secondEndpoint);
result.append(caretBoundingShape(firstCaret, secondCaret, bounds),
false);
if (firstCaret == 0 || secondCaret == 0) {
GeneralPath ls = leftShape(bounds);
if (!ls.getBounds().isEmpty())
result.append(ls, false);
}
if (firstCaret == characterCount || secondCaret == characterCount) {
GeneralPath rs = rightShape(bounds);
if (!rs.getBounds().isEmpty()) {
result.append(rs, false);
}
}
LayoutPathImpl lp = textLine.getLayoutPath();
if (lp != null) {
result = (GeneralPath)lp.mapShape(result); // dlf cast safe?
}
return result;
}
/**
* Returns a {@code Shape} enclosing the visual selection in the
* specified range, extended to the bounds. This method is a
* convenience overload of {@code getVisualHighlightShape} that
* uses the natural bounds of this {@code TextLayout}.
* @param firstEndpoint one end of the visual selection
* @param secondEndpoint the other end of the visual selection
* @return a {@code Shape} enclosing the selection. This is
* in standard coordinates.
*/
public Shape getVisualHighlightShape(TextHitInfo firstEndpoint,
TextHitInfo secondEndpoint) {
return getVisualHighlightShape(firstEndpoint, secondEndpoint, getNaturalBounds());
}
/**
* Returns a {@code Shape} enclosing the logical selection in the
* specified range, extended to the specified {@code bounds}.
* <p>
* If the selection range includes the first logical character, the
* selection is extended to the portion of {@code bounds} before
* the start of this {@code TextLayout}. If the range includes
* the last logical character, the selection is extended to the portion
* of {@code bounds} after the end of this {@code TextLayout}.
* The height (width on vertical lines) of the selection is always
* extended to {@code bounds}.
* <p>
* The selection can be discontiguous on lines with mixed-direction text.
* Only those characters in the logical range between start and limit
* appear selected. For example, consider the text 'ABCdef' where capital
* letters indicate right-to-left text, rendered on a right-to-left line,
* with a logical selection from 0 to 4 ('ABCd'). The text appears as
* follows, with bold standing in for the selection, and underlining for
* the extension:
* <br><pre>
* <u><b>d</b></u>ef<u><b>CBA </b></u>
* </pre>
* The selection is discontiguous because the selected characters are
* visually discontiguous. Also note that since the range includes the
* first logical character (A), the selection is extended to the portion
* of the {@code bounds} before the start of the layout, which in
* this case (a right-to-left line) is the right portion of the
* {@code bounds}.
* @param firstEndpoint an endpoint in the range of characters to select
* @param secondEndpoint the other endpoint of the range of characters
* to select. Can be less than {@code firstEndpoint}. The range
* includes the character at min(firstEndpoint, secondEndpoint), but
* excludes max(firstEndpoint, secondEndpoint).
* @param bounds the bounding rectangle to which to extend the selection.
* This is in baseline-relative coordinates.
* @return an area enclosing the selection. This is in standard
* coordinates.
* @see #getVisualHighlightShape(TextHitInfo, TextHitInfo, Rectangle2D)
*/
public Shape getLogicalHighlightShape(int firstEndpoint,
int secondEndpoint,
Rectangle2D bounds) {
if (bounds == null) {
throw new IllegalArgumentException("Null Rectangle2D passed to TextLayout.getLogicalHighlightShape()");
}
ensureCache();
if (firstEndpoint > secondEndpoint) {
int t = firstEndpoint;
firstEndpoint = secondEndpoint;
secondEndpoint = t;
}
if(firstEndpoint < 0 || secondEndpoint > characterCount) {
throw new IllegalArgumentException("Range is invalid in TextLayout.getLogicalHighlightShape()");
}
GeneralPath result = new GeneralPath(GeneralPath.WIND_EVEN_ODD);
int[] carets = new int[10]; // would this ever not handle all cases?
int count = 0;
if (firstEndpoint < secondEndpoint) {
int logIndex = firstEndpoint;
do {
carets[count++] = hitToCaret(TextHitInfo.leading(logIndex));
boolean ltr = textLine.isCharLTR(logIndex);
do {
logIndex++;
} while (logIndex < secondEndpoint && textLine.isCharLTR(logIndex) == ltr);
int hitCh = logIndex;
carets[count++] = hitToCaret(TextHitInfo.trailing(hitCh - 1));
if (count == carets.length) {
int[] temp = new int[carets.length + 10];
System.arraycopy(carets, 0, temp, 0, count);
carets = temp;
}
} while (logIndex < secondEndpoint);
}
else {
count = 2;
carets[0] = carets[1] = hitToCaret(TextHitInfo.leading(firstEndpoint));
}
// now create paths for pairs of carets
for (int i = 0; i < count; i += 2) {
result.append(caretBoundingShape(carets[i], carets[i+1], bounds),
false);
}
if (firstEndpoint != secondEndpoint) {
if ((textLine.isDirectionLTR() && firstEndpoint == 0) || (!textLine.isDirectionLTR() &&
secondEndpoint == characterCount)) {
GeneralPath ls = leftShape(bounds);
if (!ls.getBounds().isEmpty()) {
result.append(ls, false);
}
}
if ((textLine.isDirectionLTR() && secondEndpoint == characterCount) ||
(!textLine.isDirectionLTR() && firstEndpoint == 0)) {
GeneralPath rs = rightShape(bounds);
if (!rs.getBounds().isEmpty()) {
result.append(rs, false);
}
}
}
LayoutPathImpl lp = textLine.getLayoutPath();
if (lp != null) {
result = (GeneralPath)lp.mapShape(result); // dlf cast safe?
}
return result;
}
/**
* Returns a {@code Shape} enclosing the logical selection in the
* specified range, extended to the natural bounds of this
* {@code TextLayout}. This method is a convenience overload of
* {@code getLogicalHighlightShape} that uses the natural bounds of
* this {@code TextLayout}.
* @param firstEndpoint an endpoint in the range of characters to select
* @param secondEndpoint the other endpoint of the range of characters
* to select. Can be less than {@code firstEndpoint}. The range
* includes the character at min(firstEndpoint, secondEndpoint), but
* excludes max(firstEndpoint, secondEndpoint).
* @return a {@code Shape} enclosing the selection. This is in
* standard coordinates.
*/
public Shape getLogicalHighlightShape(int firstEndpoint, int secondEndpoint) {
return getLogicalHighlightShape(firstEndpoint, secondEndpoint, getNaturalBounds());
}
/**
* Returns the black box bounds of the characters in the specified range.
* The black box bounds is an area consisting of the union of the bounding
* boxes of all the glyphs corresponding to the characters between start
* and limit. This area can be disjoint.
* @param firstEndpoint one end of the character range
* @param secondEndpoint the other end of the character range. Can be
* less than {@code firstEndpoint}.
* @return a {@code Shape} enclosing the black box bounds. This is
* in standard coordinates.
*/
public Shape getBlackBoxBounds(int firstEndpoint, int secondEndpoint) {
ensureCache();
if (firstEndpoint > secondEndpoint) {
int t = firstEndpoint;
firstEndpoint = secondEndpoint;
secondEndpoint = t;
}
if (firstEndpoint < 0 || secondEndpoint > characterCount) {
throw new IllegalArgumentException("Invalid range passed to TextLayout.getBlackBoxBounds()");
}
/*
* return an area that consists of the bounding boxes of all the
* characters from firstEndpoint to limit
*/
GeneralPath result = new GeneralPath(GeneralPath.WIND_NON_ZERO);
if (firstEndpoint < characterCount) {
for (int logIndex = firstEndpoint;
logIndex < secondEndpoint;
logIndex++) {
Rectangle2D r = textLine.getCharBounds(logIndex);
if (!r.isEmpty()) {
result.append(r, false);
}
}
}
if (dx != 0 || dy != 0) {
AffineTransform tx = AffineTransform.getTranslateInstance(dx, dy);
result = (GeneralPath)tx.createTransformedShape(result);
}
LayoutPathImpl lp = textLine.getLayoutPath();
if (lp != null) {
result = (GeneralPath)lp.mapShape(result);
}
//return new Highlight(result, false);
return result;
}
/**
* Returns the distance from the point (x,&nbsp;y) to the caret along
* the line direction defined in {@code caretInfo}. Distance is
* negative if the point is to the left of the caret on a horizontal
* line, or above the caret on a vertical line.
* Utility for use by hitTestChar.
*/
private float caretToPointDistance(float[] caretInfo, float x, float y) {
// distanceOffBaseline is negative if you're 'above' baseline
float lineDistance = isVerticalLine? y : x;
float distanceOffBaseline = isVerticalLine? -x : y;
return lineDistance - caretInfo[0] +
(distanceOffBaseline*caretInfo[1]);
}
/**
* Returns a {@code TextHitInfo} corresponding to the
* specified point.
* Coordinates outside the bounds of the {@code TextLayout}
* map to hits on the leading edge of the first logical character,
* or the trailing edge of the last logical character, as appropriate,
* regardless of the position of that character in the line. Only the
* direction along the baseline is used to make this evaluation.
* @param x the x offset from the origin of this
* {@code TextLayout}. This is in standard coordinates.
* @param y the y offset from the origin of this
* {@code TextLayout}. This is in standard coordinates.
* @param bounds the bounds of the {@code TextLayout}. This
* is in baseline-relative coordinates.
* @return a hit describing the character and edge (leading or trailing)
* under the specified point.
*/
public TextHitInfo hitTestChar(float x, float y, Rectangle2D bounds) {
// check boundary conditions
LayoutPathImpl lp = textLine.getLayoutPath();
boolean prev = false;
if (lp != null) {
Point2D.Float pt = new Point2D.Float(x, y);
prev = lp.pointToPath(pt, pt);
x = pt.x;
y = pt.y;
}
if (isVertical()) {
if (y < bounds.getMinY()) {
return TextHitInfo.leading(0);
} else if (y >= bounds.getMaxY()) {
return TextHitInfo.trailing(characterCount-1);
}
} else {
if (x < bounds.getMinX()) {
return isLeftToRight() ? TextHitInfo.leading(0) : TextHitInfo.trailing(characterCount-1);
} else if (x >= bounds.getMaxX()) {
return isLeftToRight() ? TextHitInfo.trailing(characterCount-1) : TextHitInfo.leading(0);
}
}
// revised hit test
// the original seems too complex and fails miserably with italic offsets
// the natural tendency is to move towards the character you want to hit
// so we'll just measure distance to the center of each character's visual
// bounds, pick the closest one, then see which side of the character's
// center line (italic) the point is on.
// this tends to make it easier to hit narrow characters, which can be a
// bit odd if you're visually over an adjacent wide character. this makes
// a difference with bidi, so perhaps i need to revisit this yet again.
double distance = Double.MAX_VALUE;
int index = 0;
int trail = -1;
CoreMetrics lcm = null;
float icx = 0, icy = 0, ia = 0, cy = 0, dya = 0, ydsq = 0;
for (int i = 0; i < characterCount; ++i) {
if (!textLine.caretAtOffsetIsValid(i)) {
continue;
}
if (trail == -1) {
trail = i;
}
CoreMetrics cm = textLine.getCoreMetricsAt(i);
if (cm != lcm) {
lcm = cm;
// just work around baseline mess for now
if (cm.baselineIndex == GraphicAttribute.TOP_ALIGNMENT) {
cy = -(textLine.getMetrics().ascent - cm.ascent) + cm.ssOffset;
} else if (cm.baselineIndex == GraphicAttribute.BOTTOM_ALIGNMENT) {
cy = textLine.getMetrics().descent - cm.descent + cm.ssOffset;
} else {
cy = cm.effectiveBaselineOffset(baselineOffsets) + cm.ssOffset;
}
float dy = (cm.descent - cm.ascent) / 2 - cy;
dya = dy * cm.italicAngle;
cy += dy;
ydsq = (cy - y)*(cy - y);
}
float cx = textLine.getCharXPosition(i);
float ca = textLine.getCharAdvance(i);
float dx = ca / 2;
cx += dx - dya;
// proximity in x (along baseline) is two times as important as proximity in y
double nd = Math.sqrt(4*(cx - x)*(cx - x) + ydsq);
if (nd < distance) {
distance = nd;
index = i;
trail = -1;
icx = cx; icy = cy; ia = cm.italicAngle;
}
}
boolean left = x < icx - (y - icy) * ia;
boolean leading = textLine.isCharLTR(index) == left;
if (trail == -1) {
trail = characterCount;
}
TextHitInfo result = leading ? TextHitInfo.leading(index) :
TextHitInfo.trailing(trail-1);
return result;
}
/**
* Returns a {@code TextHitInfo} corresponding to the
* specified point. This method is a convenience overload of
* {@code hitTestChar} that uses the natural bounds of this
* {@code TextLayout}.
* @param x the x offset from the origin of this
* {@code TextLayout}. This is in standard coordinates.
* @param y the y offset from the origin of this
* {@code TextLayout}. This is in standard coordinates.
* @return a hit describing the character and edge (leading or trailing)
* under the specified point.
*/
public TextHitInfo hitTestChar(float x, float y) {
return hitTestChar(x, y, getNaturalBounds());
}
/**
* Returns {@code true} if the two layouts are equal.
* Obeys the general contract of {@link java.lang.Object equals(Object)}.
* @param rhs the {@code TextLayout} to compare to this
* {@code TextLayout}
* @return {@code true} if the specified {@code TextLayout}
* equals this {@code TextLayout}.
*
*/
public boolean equals(TextLayout rhs) {
return equals((Object)rhs);
}
/**
* Returns debugging information for this {@code TextLayout}.
* @return the {@code textLine} of this {@code TextLayout}
* as a {@code String}.
*/
public String toString() {
ensureCache();
return textLine.toString();
}
/**
* Renders this {@code TextLayout} at the specified location in
* the specified {@link java.awt.Graphics2D Graphics2D} context.
* The origin of the layout is placed at x,&nbsp;y. Rendering may touch
* any point within {@code getBounds()} of this position. This
* leaves the {@code g2} unchanged. Text is rendered along the
* baseline path.
* @param g2 the {@code Graphics2D} context into which to render
* the layout
* @param x the X coordinate of the origin of this {@code TextLayout}
* @param y the Y coordinate of the origin of this {@code TextLayout}
* @see #getBounds()
*/
public void draw(Graphics2D g2, float x, float y) {
if (g2 == null) {
throw new IllegalArgumentException("Null Graphics2D passed to TextLayout.draw()");
}
textLine.draw(g2, x - dx, y - dy);
}
/**
* Package-only method for testing ONLY. Please don't abuse.
*/
TextLine getTextLineForTesting() {
return textLine;
}
/**
*
* Return the index of the first character with a different baseline from the
* character at start, or limit if all characters between start and limit have
* the same baseline.
*/
private static int sameBaselineUpTo(Font font, char[] text,
int start, int limit) {
// current implementation doesn't support multiple baselines
return limit;
/*
byte bl = font.getBaselineFor(text[start++]);
while (start < limit && font.getBaselineFor(text[start]) == bl) {
++start;
}
return start;
*/
}
static byte getBaselineFromGraphic(GraphicAttribute graphic) {
if (graphic == null) {
return (byte)GraphicAttribute.ROMAN_BASELINE;
}
byte alignment = (byte) graphic.getAlignment();
if (alignment == GraphicAttribute.BOTTOM_ALIGNMENT ||
alignment == GraphicAttribute.TOP_ALIGNMENT) {
return (byte)GraphicAttribute.ROMAN_BASELINE;
}
else {
return alignment;
}
}
/**
* Returns a {@code Shape} representing the outline of this
* {@code TextLayout}.
* @param tx an optional {@link AffineTransform} to apply to the
* outline of this {@code TextLayout}.
* @return a {@code Shape} that is the outline of this
* {@code TextLayout}. This is in standard coordinates.
*/
public Shape getOutline(AffineTransform tx) {
ensureCache();
Shape result = textLine.getOutline();
LayoutPathImpl lp = textLine.getLayoutPath();
if (lp != null) {
result = lp.mapShape(result);
}
if (tx != null) {
if (result instanceof GeneralPath gp) {
// transform in place
gp.transform(tx);
} else {
// create a transformed copy
result = tx.createTransformedShape(result);
}
}
return result;
}
/**
* Return the LayoutPath, or null if the layout path is the
* default path (x maps to advance, y maps to offset).
* @return the layout path
* @since 1.6
*/
public LayoutPath getLayoutPath() {
return textLine.getLayoutPath();
}
/**
* Convert a hit to a point in standard coordinates. The point is
* on the baseline of the character at the leading or trailing
* edge of the character, as appropriate. If the path is
* broken at the side of the character represented by the hit, the
* point will be adjacent to the character.
* @param hit the hit to check. This must be a valid hit on
* the TextLayout.
* @param point the returned point. The point is in standard
* coordinates.
* @throws IllegalArgumentException if the hit is not valid for the
* TextLayout.
* @throws NullPointerException if hit or point is null.
* @since 1.6
*/
public void hitToPoint(TextHitInfo hit, Point2D point) {
if (hit == null || point == null) {
throw new NullPointerException((hit == null ? "hit" : "point") +
" can't be null");
}
ensureCache();
checkTextHit(hit);
float adv = 0;
float off = 0;
int ix = hit.getCharIndex();
boolean leading = hit.isLeadingEdge();
boolean ltr;
if (ix == -1 || ix == textLine.characterCount()) {
ltr = textLine.isDirectionLTR();
adv = (ltr == (ix == -1)) ? 0 : lineMetrics.advance;
} else {
ltr = textLine.isCharLTR(ix);
adv = textLine.getCharLinePosition(ix, leading);
off = textLine.getCharYPosition(ix);
}
point.setLocation(adv, off);
LayoutPath lp = textLine.getLayoutPath();
if (lp != null) {
lp.pathToPoint(point, ltr != leading, point);
}
}
}