GlyphMetrics JDK 1.6)

Description

publicfinal class GlyphMetrics

The GlyphMetrics class represents infomation for a single glyph.

The GlyphMetrics class represents infomation 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();

See also: Font GlyphVector

Constructors

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

Constructs a GlyphMetrics object.

Constructs a GlyphMetrics object.
Parameters:
- horizontal - if true, metrics are for a horizontal baseline, otherwise they are for a vertical baseline
- advanceX - the X-component of the glyph's advance
- advanceY - the Y-component of the glyph's advance
- bounds - the visual bounds of the glyph
- glyphType - the type of the glyph
Since: 1.4

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

Constructs a GlyphMetrics object.

Constructs a GlyphMetrics object.
Parameters:
- advance - the advance width of the glyph
- bounds - the black box bounds of the glyph
- glyphType - the type of the glyph

Methods

Hide/Show inherited methods

public float getAdvance ()

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

public float getAdvanceX ()

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

public float getAdvanceY ()

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

public Rectangle2D getBounds2D ()

Returns the bounds of the glyph.

public float getLSB ()

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

public float getRSB ()

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

public int getType ()

Returns the raw glyph type code.

public boolean isCombining ()

Returns true if this is a combining glyph.

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

public boolean isComponent ()

Returns true if this is a component glyph.

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

public boolean isLigature ()

Returns true if this is a ligature glyph.

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

public boolean isStandard ()

Returns true if this is a standard glyph.

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

public boolean isWhitespace ()

Returns true if this is a whitespace glyph.

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

Fields

Hide/Show inherited fields

publicfinalstatic byte COMBINING = "2"

Indicates a glyph that represents a combining character, such as an umlaut.

publicfinalstatic byte COMPONENT = "3"

Indicates a glyph with no corresponding character in the backing store.

publicfinalstatic byte LIGATURE = "1"

Indicates a glyph that represents multiple characters as a ligature, for example 'fi' or 'ffi'.

publicfinalstatic byte STANDARD = "0"

Indicates a glyph that represents a single standard character.

publicfinalstatic byte WHITESPACE = "4"

Indicates a glyph with no visual representation.