A GlyphVector object is a collection of glyphs
containing geometric information for the placement of each glyph
in a transformed coordinate space which corresponds to the
device on which the GlyphVector is ultimately
displayed.
The GlyphVector does not attempt any interpretation of
the sequence of glyphs it contains. Relationships between adjacent
glyphs in sequence are solely used to determine the placement of
the glyphs in the visual coordinate space.
Instances of GlyphVector are created by a Font.
In a text processing application that can cache intermediate
representations of text, creation and subsequent caching of a
GlyphVector for use during rendering is the fastest
method to present the visual representation of characters to a user.
A GlyphVector is associated with exactly one
Font, and can provide data useful only in relation to
this Font. In addition, metrics obtained from a
GlyphVector are not generally geometrically scaleable
since the pixelization and spacing are dependent on grid-fitting
algorithms within a Font. To facilitate accurate
measurement of a GlyphVector and its component
glyphs, you must specify a scaling transform, anti-alias mode, and
fractional metrics mode when creating the GlyphVector.
These characteristics can be derived from the destination device.
For each glyph in the GlyphVector, you can obtain:
the position of the glyph
the transform associated with the glyph
the metrics of the glyph in the context of the
GlyphVector. The metrics of the glyph may be
different under different transforms, application specified
rendering hints, and the specific instance of the glyph within
the GlyphVector.
Altering the data used to create the GlyphVector does not
alter the state of the GlyphVector.
Methods are provided to adjust the positions of the glyphs
within the GlyphVector. These methods are most
appropriate for applications that are performing justification
operations for the presentation of the glyphs.
Methods are provided to transform individual glyphs within the
GlyphVector. These methods are primarily useful for
special effects.
Methods are provided to return both the visual, logical, and pixel bounds
of the entire GlyphVector or of individual glyphs within
the GlyphVector.
Methods are provided to return a Shape for the
GlyphVector, and for individual glyphs within the
GlyphVector.
Class Variables
FLAG_HAS_TRANSFORMS public static final int
A flag used with getLayoutFlags that indicates that this GlyphVector has
per-glyph transforms.
FLAG_HAS_POSITION_ADJUSTMENTS public static final int
A flag used with getLayoutFlags that indicates that this GlyphVector has
position adjustments. When this is true, the glyph positions don't match the
accumulated default advances of the glyphs (for example, if kerning has been done).
FLAG_RUN_RTL public static final int
A flag used with getLayoutFlags that indicates that this GlyphVector has
a right-to-left run direction. This refers to the glyph-to-char mapping and does
not imply that the visual locations of the glyphs are necessarily in this order,
although generally they will be.
FLAG_COMPLEX_GLYPHS public static final int
A flag used with getLayoutFlags that indicates that this GlyphVector has
a complex glyph-to-char mapping (one that does not map glyphs to chars one-to-one in
strictly ascending or descending order matching the run direction).
FLAG_MASK public static final int
A mask for supported flags from getLayoutFlags. Only bits covered by the mask
should be tested.
Instance Variables
None declared in this class.
Constructors
GlyphVector
public GlyphVector(
)
No description available for this constructor.
Class Methods
None declared in this class.
Instance Methods
equals
public abstract boolean equals(
GlyphVectorset
)
Tests if the specified GlyphVector exactly
equals this GlyphVector.
Returns the Font associated with this
GlyphVector.
getFontRenderContext
public abstract FontRenderContext getFontRenderContext(
)
Returns the FontRenderContext associated with this
GlyphVector.
getGlyphCharIndex
public int getGlyphCharIndex(
int glyphIndex
)
Returns the character index of the specified glyph.
The character index is the index of the first logical
character represented by the glyph. The default
implementation assumes a one-to-one, left-to-right mapping
of glyphs to characters.
getGlyphCharIndices
public int[] getGlyphCharIndices(
int beginGlyphIndex,
int numEntries,
int[] codeReturn
)
Returns the character indices of the specified glyphs.
The character index is the index of the first logical
character represented by the glyph. Indices are returned
in glyph order. The default implementation invokes
getGlyphCharIndex for each glyph, and subclassers will probably
want to override this implementation for performance reasons.
Use this method for convenience and performance
in processing of glyphcodes. If no array is passed in,
a new array is created.
getGlyphCode
public abstract int getGlyphCode(
int glyphIndex
)
Returns the glyphcode of the specified glyph.
This return value is meaningless to anything other
than the Font object that created this
GlyphVector.
getGlyphCodes
public abstract int[] getGlyphCodes(
int beginGlyphIndex,
int numEntries,
int[] codeReturn
)
Returns an array of glyphcodes for the specified glyphs.
The contents of this return value are meaningless to anything other
than the Font used to create this
GlyphVector. This method is used
for convenience and performance when processing glyphcodes.
If no array is passed in, a new array is created.
getGlyphJustificationInfo
public abstract GlyphJustificationInfo getGlyphJustificationInfo(
int glyphIndex
)
Returns the justification information for the glyph at
the specified index into this GlyphVector.
getGlyphLogicalBounds
public abstract Shape getGlyphLogicalBounds(
int glyphIndex
)
Returns the logical bounds of the specified glyph within this
GlyphVector.
These logical bounds have a total of four edges, with two edges
parallel to the baseline under the glyph's transform and the other two
edges are shared with adjacent glyphs if they are present. This
method is useful for hit-testing of the specified glyph,
positioning of a caret at the leading or trailing edge of a glyph,
and for drawing a highlight region around the specified glyph.
getGlyphMetrics
public abstract GlyphMetrics getGlyphMetrics(
int glyphIndex
)
Returns the metrics of the glyph at the specified index into
this GlyphVector.
getGlyphOutline
public abstract Shape getGlyphOutline(
int glyphIndex
)
Returns a Shape whose interior corresponds to the
visual representation of the specified glyph
within this GlyphVector.
The outline returned by this method is positioned around the
origin of each individual glyph.
getGlyphOutline
public Shape getGlyphOutline(
int glyphIndex,
float x,
float y
)
Returns a Shape whose interior corresponds to the
visual representation of the specified glyph
within this GlyphVector, offset to x, y.
The outline returned by this method is positioned around the
origin of each individual glyph.
getGlyphPixelBounds
public Rectangle getGlyphPixelBounds(
int index,
FontRenderContextrenderFRC,
float x,
float y
)
Returns the pixel bounds of the glyph at index when this
GlyphVector is rendered in a Graphics with the
given FontRenderContext at the given location. The
renderFRC need not be the same as the
FontRenderContext of this
GlyphVector, and can be null. If it is null, the
FontRenderContext of this GlyphVector
is used. The default implementation returns the visual bounds of the glyph,
offset to x, y and rounded out to the next integer value, and
ignores the FRC. Subclassers should override this method.
getGlyphPosition
public abstract Point2D getGlyphPosition(
int glyphIndex
)
Returns the position of the specified glyph relative to the
origin of this GlyphVector.
If glyphIndex equals the number of of glyphs in
this GlyphVector, this method returns the position after
the last glyph. This position is used to define the advance of
the entire GlyphVector.
getGlyphPositions
public abstract float[] getGlyphPositions(
int beginGlyphIndex,
int numEntries,
float[] positionReturn
)
Returns an array of glyph positions for the specified glyphs.
This method is used for convenience and performance when
processing glyph positions.
If no array is passed in, a new array is created.
Even numbered array entries beginning with position zero are the X
coordinates of the glyph numbered beginGlyphIndex + position/2.
Odd numbered array entries beginning with position one are the Y
coordinates of the glyph numbered beginGlyphIndex + (position-1)/2.
If beginGlyphIndex equals the number of of glyphs in
this GlyphVector, this method gets the position after
the last glyph and this position is used to define the advance of
the entire GlyphVector.
getGlyphTransform
public abstract AffineTransform getGlyphTransform(
int glyphIndex
)
Returns the transform of the specified glyph within this
GlyphVector. The transform is relative to the
glyph position. If no special transform has been applied,
null can be returned. A null return indicates
an identity transform.
getGlyphVisualBounds
public abstract Shape getGlyphVisualBounds(
int glyphIndex
)
Returns the visual bounds of the specified glyph within the
GlyphVector.
The bounds returned by this method is positioned around the
origin of each individual glyph.
getLayoutFlags
public int getLayoutFlags(
)
Returns flags describing the global state of the GlyphVector.
Flags not described below are reserved. The default
implementation returns 0 (meaning false) for the position adjustments,
transforms, rtl, and complex flags.
Subclassers should override this method, and make sure
it correctly describes the GlyphVector and corresponds
to the results of related calls.
getLogicalBounds
public abstract Rectangle2D getLogicalBounds(
)
Returns the logical bounds of this GlyphVector.
This method is used when positioning this GlyphVector
in relation to visually adjacent GlyphVector objects.
Returns the pixel bounds of this GlyphVector when
rendered in a graphics with the given
FontRenderContext at the given location. The
renderFRC need not be the same as the
FontRenderContext of this
GlyphVector, and can be null. If it is null, the
FontRenderContext of this GlyphVector
is used. The default implementation returns the visual bounds,
offset to x, y and rounded out to the next integer value (i.e. returns an
integer rectangle which encloses the visual bounds) and
ignores the FRC. Subclassers should override this method.
getVisualBounds
public abstract Rectangle2D getVisualBounds(
)
Returns the visual bounds of this GlyphVector
The visual bounds is the bounding box of the outline of this
GlyphVector. Because of rasterization and
alignment of pixels, it is possible that this box does not
enclose all pixels affected by rendering this GlyphVector.
performDefaultLayout
public abstract void performDefaultLayout(
)
Assigns default positions to each glyph in this
GlyphVector. This can destroy information
generated during initial layout of this GlyphVector.
setGlyphPosition
public abstract void setGlyphPosition(
int glyphIndex,
Point2DnewPos
)
Sets the position of the specified glyph within this
GlyphVector.
If glyphIndex equals the number of of glyphs in
this GlyphVector, this method sets the position after
the last glyph. This position is used to define the advance of
the entire GlyphVector.
setGlyphTransform
public abstract void setGlyphTransform(
int glyphIndex,
AffineTransformnewTX
)
Sets the transform of the specified glyph within this
GlyphVector. The transform is relative to the glyph
position. A null argument for newTX
indicates that no special transform is applied for the specified
glyph.
This method can be used to rotate, mirror, translate and scale the
glyph. Adding a transform can result in signifant performance changes.