OpenJDK 27 · java.awt.font.GlyphMetrics · APIdia, the JavaDoc alternative

The GlyphMetrics class represents information for a single glyph. A glyph is the visual representation of one or more characters. Many different glyphs can be used to represent a single character or combination of characters. GlyphMetrics instances are produced by Font and are applicable to a specific glyph in a particular Font.

Glyphs are either STANDARD, LIGATURE, COMBINING, or COMPONENT.

STANDARD glyphs are commonly used to represent single characters.
LIGATURE glyphs are used to represent sequences of characters.
COMPONENT glyphs in a GlyphVector do not correspond to a particular character in a text model. Instead, COMPONENT glyphs are added for typographical reasons, such as Arabic justification.
COMBINING glyphs embellish STANDARD or LIGATURE glyphs, such as accent marks. Carets do not appear before COMBINING glyphs.

Other metrics available through GlyphMetrics are the components of the advance, the visual bounds, and the left and right side bearings.

Glyphs for a rotated font, or obtained from a GlyphVector which has applied a rotation to the glyph, can have advances that contain both X and Y components. Usually the advance only has one component.

The advance of a glyph is the distance from the glyph's origin to the origin of the next glyph along the baseline, which is either vertical or horizontal. Note that, in a GlyphVector, the distance from a glyph to its following glyph might not be the glyph's advance, because of kerning or other positioning adjustments.

The bounds is the smallest rectangle that completely contains the outline of the glyph. The bounds rectangle is relative to the glyph's origin. The left-side bearing is the distance from the glyph origin to the left of its bounds rectangle. If the left-side bearing is negative, part of the glyph is drawn to the left of its origin. The right-side bearing is the distance from the right side of the bounds rectangle to the next glyph origin (the origin plus the advance). If negative, part of the glyph is drawn to the right of the next glyph's origin. Note that the bounds does not necessarily enclose all the pixels affected when rendering the glyph, because of rasterization and pixel adjustment effects.

Although instances of GlyphMetrics can be directly constructed, they are almost always obtained from a GlyphVector. Once constructed, GlyphMetrics objects are immutable.

Example:

Querying a Font for glyph information

Font font = ...;
int glyphIndex = ...;
GlyphMetrics metrics = GlyphVector.getGlyphMetrics(glyphIndex);
int isStandard = metrics.isStandard();
float glyphAdvance = metrics.getAdvance();

Field Summary

Modifier and Type	Field and Description
private float	advanceX The x-component of the advance.
private float	advanceY The y-component of the advance.
private Rectangle2D.Float	bounds The bounds of the associated glyph.
public static final byte	COMBINING Indicates a glyph that represents a combining character, such as an umlaut.
public static final byte	COMPONENT Indicates a glyph with no corresponding character in the backing store.
private byte	glyphType Additional information about the glyph encoded as a byte.
private boolean	horizontal Indicates whether the metrics are for a horizontal or vertical baseline.
public static final byte	LIGATURE Indicates a glyph that represents multiple characters as a ligature, for example 'fi' or 'ffi'.
public static final byte	STANDARD Indicates a glyph that represents a single standard character.
public static final byte	WHITESPACE Indicates a glyph with no visual representation.

Constructor Summary

Access	Constructor and Description
public	GlyphMetrics(float the advance width of the glyph advance, Rectangle2D the black box bounds of the glyph bounds, byte the type of the glyph glyphType) Constructs a `GlyphMetrics` object.
public	GlyphMetrics(boolean if true, metrics are for a horizontal baseline, otherwise they are for a vertical baseline horizontal, float the X-component of the glyph's advance advanceX, float the Y-component of the glyph's advance advanceY, Rectangle2D the visual bounds of the glyph bounds, byte the type of the glyph glyphType) Constructs a `GlyphMetrics` object.

Method Summary

Modifier and Type	Method and Description
public float	Returns: the advance of the glyph getAdvance() Returns the advance of the glyph along the baseline (either horizontal or vertical).
public float	Returns: the x-component of the advance of the glyph getAdvanceX() Returns the x-component of the advance of the glyph.
public float	Returns: the y-component of the advance of the glyph getAdvanceY() Returns the y-component of the advance of the glyph.
public Rectangle2D	Returns: a `Rectangle2D` that is the bounds of the glyph. getBounds2D() Returns the bounds of the glyph.
public float	Returns: the left side bearing of the glyph. getLSB() Returns the left (top) side bearing of the glyph.
public float	Returns: the right side bearing of the glyph. getRSB() Returns the right (bottom) side bearing of the glyph.
public int	Returns: the raw glyph type code. getType() Returns the raw glyph type code.
public boolean	Returns: `true` if this is a combining glyph; `false` otherwise. isCombining() Returns `true` if this is a combining glyph.
public boolean	Returns: `true` if this is a component glyph; `false` otherwise. isComponent() Returns `true` if this is a component glyph.
public boolean	Returns: `true` if this is a ligature glyph; `false` otherwise. isLigature() Returns `true` if this is a ligature glyph.
public boolean	Returns: `true` if this is a standard glyph; `false` otherwise. isStandard() Returns `true` if this is a standard glyph.
public boolean	Returns: `true` if this is a whitespace glyph; `false` otherwise. isWhitespace() Returns `true` if this is a whitespace glyph.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

advanceX	back to summary
private float advanceX The x-component of the advance.

advanceY	back to summary
private float advanceY The y-component of the advance.

bounds	back to summary
private Rectangle2D.Float bounds The bounds of the associated glyph.

COMBINING	back to summary
public static final byte COMBINING Indicates a glyph that represents a combining character, such as an umlaut. There is no caret position between this glyph and the preceding glyph.

COMPONENT	back to summary
public static final byte COMPONENT Indicates a glyph with no corresponding character in the backing store. The glyph is associated with the character represented by the logically preceding non-component glyph. This is used for kashida justification or other visual modifications to existing glyphs. There is no caret position between this glyph and the preceding glyph.

glyphType	back to summary
private byte glyphType Additional information about the glyph encoded as a byte.

horizontal	back to summary
private boolean horizontal Indicates whether the metrics are for a horizontal or vertical baseline.

LIGATURE	back to summary
public static final byte LIGATURE Indicates a glyph that represents multiple characters as a ligature, for example 'fi' or 'ffi'. It is followed by filler glyphs for the remaining characters. Filler and combining glyphs can be intermixed to control positioning of accent marks on the logically preceding ligature.

STANDARD	back to summary
public static final byte STANDARD Indicates a glyph that represents a single standard character.

WHITESPACE	back to summary
public static final byte WHITESPACE Indicates a glyph with no visual representation. It can be added to the other code values to indicate an invisible glyph.

Constructor Detail

GlyphMetrics back to summary

GlyphMetrics	back to summary
public GlyphMetrics(float advance, Rectangle2D bounds, byte glyphType) Constructs a `GlyphMetrics` object. Parameters advance:float the advance width of the glyph bounds:Rectangle2D the black box bounds of the glyph glyphType:byte the type of the glyph

public GlyphMetrics(float advance, Rectangle2D bounds, byte glyphType)

Constructs a GlyphMetrics object.

Parameters

advance:float: the advance width of the glyph
bounds:Rectangle2D: the black box bounds of the glyph
glyphType:byte: the type of the glyph

GlyphMetrics back to summary

GlyphMetrics	back to summary
public GlyphMetrics(boolean horizontal, float advanceX, float advanceY, Rectangle2D bounds, byte glyphType) Constructs a `GlyphMetrics` object. Parameters horizontal:boolean if true, metrics are for a horizontal baseline, otherwise they are for a vertical baseline advanceX:float the X-component of the glyph's advance advanceY:float the Y-component of the glyph's advance bounds:Rectangle2D the visual bounds of the glyph glyphType:byte the type of the glyph Since 1.4

public GlyphMetrics(boolean horizontal, float advanceX, float advanceY, Rectangle2D bounds, byte glyphType)

Constructs a GlyphMetrics object.

Parameters

horizontal:boolean: if true, metrics are for a horizontal baseline, otherwise they are for a vertical baseline
advanceX:float: the X-component of the glyph's advance
advanceY:float: the Y-component of the glyph's advance
bounds:Rectangle2D: the visual bounds of the glyph
glyphType:byte: the type of the glyph

Since

1.4

Method Detail

getAdvance	back to summary
public float getAdvance() Returns the advance of the glyph along the baseline (either horizontal or vertical). Returns:float the advance of the glyph

getAdvance

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public float getAdvance()

Returns the advance of the glyph along the baseline (either horizontal or vertical).

Returns:float: the advance of the glyph

getAdvanceX	back to summary
public float getAdvanceX() Returns the x-component of the advance of the glyph. Returns:float the x-component of the advance of the glyph Since 1.4

getAdvanceX

back to summary

public float getAdvanceX()

Returns the x-component of the advance of the glyph.

Returns:float: the x-component of the advance of the glyph
Since: 1.4

getAdvanceY	back to summary
public float getAdvanceY() Returns the y-component of the advance of the glyph. Returns:float the y-component of the advance of the glyph Since 1.4

getAdvanceY

back to summary

public float getAdvanceY()

Returns the y-component of the advance of the glyph.

Returns:float: the y-component of the advance of the glyph
Since: 1.4

getBounds2D back to summary

getBounds2D	back to summary
public Rectangle2D getBounds2D() Returns the bounds of the glyph. This is the bounding box of the glyph outline. Because of rasterization and pixel alignment effects, it does not necessarily enclose the pixels that are affected when rendering the glyph. Returns:Rectangle2D a `Rectangle2D` that is the bounds of the glyph.

public Rectangle2D getBounds2D()

Returns the bounds of the glyph. This is the bounding box of the glyph outline. Because of rasterization and pixel alignment effects, it does not necessarily enclose the pixels that are affected when rendering the glyph.

Returns:Rectangle2D: a Rectangle2D that is the bounds of the glyph.

getLSB	back to summary
public float getLSB() Returns the left (top) side bearing of the glyph. This is the distance from 0, 0 to the left (top) of the glyph bounds. If the bounds of the glyph is to the left of (above) the origin, the LSB is negative. Returns:float the left side bearing of the glyph.

getLSB

back to summary

public float getLSB()

Returns the left (top) side bearing of the glyph.

This is the distance from 0, 0 to the left (top) of the glyph bounds. If the bounds of the glyph is to the left of (above) the origin, the LSB is negative.

Returns:float: the left side bearing of the glyph.

getRSB	back to summary
public float getRSB() Returns the right (bottom) side bearing of the glyph. This is the distance from the right (bottom) of the glyph bounds to the advance. If the bounds of the glyph is to the right of (below) the advance, the RSB is negative. Returns:float the right side bearing of the glyph.

getRSB

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public float getRSB()

Returns the right (bottom) side bearing of the glyph.

This is the distance from the right (bottom) of the glyph bounds to the advance. If the bounds of the glyph is to the right of (below) the advance, the RSB is negative.

Returns:float: the right side bearing of the glyph.

getType	back to summary
public int getType() Returns the raw glyph type code. Returns:int the raw glyph type code.

getType

back to summary

public int getType()

Returns the raw glyph type code.

Returns:int: the raw glyph type code.

isCombining back to summary

isCombining	back to summary
public boolean isCombining() Returns `true` if this is a combining glyph. Returns:boolean `true` if this is a combining glyph; `false` otherwise.

public boolean isCombining()

Returns true if this is a combining glyph.

Returns:boolean: true if this is a combining glyph; false otherwise.

isComponent back to summary

isComponent	back to summary
public boolean isComponent() Returns `true` if this is a component glyph. Returns:boolean `true` if this is a component glyph; `false` otherwise.

public boolean isComponent()

Returns true if this is a component glyph.

Returns:boolean: true if this is a component glyph; false otherwise.

isLigature back to summary

isLigature	back to summary
public boolean isLigature() Returns `true` if this is a ligature glyph. Returns:boolean `true` if this is a ligature glyph; `false` otherwise.

public boolean isLigature()

Returns true if this is a ligature glyph.

Returns:boolean: true if this is a ligature glyph; false otherwise.

isStandard back to summary

isStandard	back to summary
public boolean isStandard() Returns `true` if this is a standard glyph. Returns:boolean `true` if this is a standard glyph; `false` otherwise.

public boolean isStandard()

Returns true if this is a standard glyph.

Returns:boolean: true if this is a standard glyph; false otherwise.

isWhitespace back to summary

isWhitespace	back to summary
public boolean isWhitespace() Returns `true` if this is a whitespace glyph. Returns:boolean `true` if this is a whitespace glyph; `false` otherwise.

public boolean isWhitespace()

Returns true if this is a whitespace glyph.

Returns:boolean: true if this is a whitespace glyph; false otherwise.

public final Class GlyphMetrics

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail