Module org.freedesktop.cairo

Package org.freedesktop.cairo

Class FontExtents

java.lang.Object

io.github.jwharm.cairobindings.Proxy

org.freedesktop.cairo.FontExtents

public class FontExtents
extends Proxy

The FontExtents structure stores metric information for a font. Values are given in the current user-space coordinate system.

Because font metrics are in user-space coordinates, they are mostly, but not entirely, independent of the current transformation matrix. If you call Context.scale(2.0, 2.0), text will be drawn twice as big, but the reported text extents will not be doubled. They will change slightly due to hinting (so you can't assume that metrics are independent of the transformation matrix), but otherwise will remain unchanged.

Since:

1.0

Constructor Summary

Constructors

Constructor	Description
FontExtents(MemorySegment address)	Constructor used internally to instantiate a java FontExtents object for a native cairo_font_extents_t instance

Method Summary

Modifier and Type	Method	Description
double	ascent()	The distance that the font extends above the baseline.
static FontExtents	create(Arena arena)	Allocate a new, uninitialized cairo_font_extents_t
double	descent()	The distance that the font extends below the baseline.
double	height()	The recommended vertical distance between baselines when setting consecutive lines of text with the font.
double	maxXAdvance()	The maximum distance in the X direction that the origin is advanced for any glyph in the font.
double	maxYAdvance()	The maximum distance in the Y direction that the origin is advanced for any glyph in the font.

Methods inherited from class io.github.jwharm.cairobindings.Proxy

equals, handle, hashCode

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Details

FontExtents

public FontExtents(MemorySegment address)

Constructor used internally to instantiate a java FontExtents object for a native cairo_font_extents_t instance

Parameters:

address - the memory address of the native cairo_font_extents_t instance

Method Details

create

public static FontExtents create(Arena arena)

Allocate a new, uninitialized cairo_font_extents_t

Parameters:

arena - the arena in which the FontExtents will be allocated

Returns:

a newly allocated, uninitialized FontExtents

ascent

public double ascent()

The distance that the font extends above the baseline. Note that this is not always exactly equal to the maximum of the extents of all the glyphs in the font, but rather is picked to express the font designer's intent as to how the font should align with elements above it.

Returns:

the distance that the font extends above the baseline

descent

public double descent()

The distance that the font extends below the baseline. This value is positive for typical fonts that include portions below the baseline. Note that this is not always exactly equal to the maximum of the extents of all the glyphs in the font, but rather is picked to express the font designer's intent as to how the font should align with elements below it.

Returns:

the distance that the font extends below the baseline

height

public double height()

The recommended vertical distance between baselines when setting consecutive lines of text with the font. This is greater than ascent + descent by a quantity known as the line spacing or external leading. When space is at a premium, most fonts can be set with only a distance of ascent + descent between lines.

Returns:

the recommended vertical distance between baselines when setting consecutive lines of text with the font

maxXAdvance

public double maxXAdvance()

The maximum distance in the X direction that the origin is advanced for any glyph in the font.

Returns:

the maximum distance in the X direction that the origin is advanced for any glyph in the font

maxYAdvance

public double maxYAdvance()

The maximum distance in the Y direction that the origin is advanced for any glyph in the font. This will be zero for normal fonts used for horizontal writing. (The scripts of East Asia are sometimes written vertically.)

Returns:

the maximum distance in the Y direction that the origin is advanced for any glyph in the font