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
java.awt.Font 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: java.awt.Font
See Also: GlyphVector | 