Cairo::ScaledFont Class Reference

List of all members.


Detailed Description

A ScaledFont is a font scaled to a particular size and device resolution.

It is most useful for low-level font usage where a library or application wants to cache a reference to a scaled font to speed up the computation of metrics.

Public Types

typedef cairo_scaled_font_t cobject
 The underlying C cairo object type.

Public Member Functions

const cobjectcobj () const
 Provides acces to the underlying C cairo object.
cobjectcobj ()
 Provides acces to the underlying C cairo object.
void extents (FontExtents &extents) const
 Gets the metrics for a ScaledFont.
void get_ctm (Matrix &ctm) const
 Gets the CTM with which the ScaledFont was created.
RefPtr< FontFaceget_font_face () const
 The FontFace with which this ScaledFont was created.
void get_font_matrix (Matrix &font_matrix) const
 Gets the font matrix with which the ScaledFont was created.
void get_font_options (FontOptions &options) const
 Gets the FontOptions with which the ScaledFont was created.
FontType get_type () const
 Gets the type of scaled Font.
void glyph_extents (const std::vector< Glyph > &glyphs, TextExtents &extents)
 Gets the extents for an array of glyphs.
 ScaledFont (cobject *cobj, bool has_reference=false)
 Createa C++ wrapper object from the C instance.
void text_extents (const std::string &utf8, TextExtents &extents) const
 Gets the extents for a string of text.

Static Public Member Functions

static RefPtr< ScaledFontcreate (FontFace &font_face, const Matrix &font_matrix, const Matrix &ctm, const FontOptions &options)
 Creates a ScaledFont object from a font face and matrices that describe the size of the font and the environment in which it will be used.

Protected Attributes

cobjectm_cobject
 The underlying C cairo object that is wrapped by this ScaledFont.


Member Typedef Documentation

typedef cairo_scaled_font_t Cairo::ScaledFont::cobject

The underlying C cairo object type.


Constructor & Destructor Documentation

Cairo::ScaledFont::ScaledFont ( cobject cobj,
bool  has_reference = false 
) [explicit]

Createa C++ wrapper object from the C instance.

This C++ object should then be given to a RefPtr.


Member Function Documentation

const cobject* Cairo::ScaledFont::cobj (  )  const [inline]

Provides acces to the underlying C cairo object.

References m_cobject.

cobject* Cairo::ScaledFont::cobj (  )  [inline]

Provides acces to the underlying C cairo object.

References m_cobject.

static RefPtr<ScaledFont> Cairo::ScaledFont::create ( FontFace font_face,
const Matrix font_matrix,
const Matrix ctm,
const FontOptions options 
) [static]

Creates a ScaledFont object from a font face and matrices that describe the size of the font and the environment in which it will be used.

Parameters:
font_face A font face.
font_matrix font space to user space transformation matrix for the font. In the simplest case of a N point font, this matrix is just a scale by N, but it can also be used to shear the font or stretch it unequally along the two axes. See Context::set_font_matrix().
ctm user to device transformation matrix with which the font will be used.
options,: options to use when getting metrics for the font and rendering with it.

void Cairo::ScaledFont::extents ( FontExtents extents  )  const

Gets the metrics for a ScaledFont.

void Cairo::ScaledFont::get_ctm ( Matrix ctm  )  const

Gets the CTM with which the ScaledFont was created.

Since:
1.2

RefPtr<FontFace> Cairo::ScaledFont::get_font_face (  )  const

The FontFace with which this ScaledFont was created.

Since:
1.2

void Cairo::ScaledFont::get_font_matrix ( Matrix font_matrix  )  const

Gets the font matrix with which the ScaledFont was created.

Since:
1.2

void Cairo::ScaledFont::get_font_options ( FontOptions options  )  const

Gets the FontOptions with which the ScaledFont was created.

Since:
1.2

FontType Cairo::ScaledFont::get_type (  )  const

Gets the type of scaled Font.

Since:
1.2

void Cairo::ScaledFont::glyph_extents ( const std::vector< Glyph > &  glyphs,
TextExtents extents 
)

Gets the extents for an array of glyphs.

The extents describe a user-space rectangle that encloses the "inked" portion of the glyphs, (as they would be drawn by Context::show_glyphs() if the cairo graphics state were set to the same font_face, font_matrix, ctm, and font_options as the ScaledFont object). Additionally, the x_advance and y_advance values indicate the amount by which the current point would be advanced by Context::show_glyphs().

Note that whitespace glyphs do not contribute to the size of the rectangle (extents.width and extents.height).

Parameters:
glyphs A vector of glyphs to calculate the extents of
extents Returns the extents for the array of glyphs

void Cairo::ScaledFont::text_extents ( const std::string &  utf8,
TextExtents extents 
) const

Gets the extents for a string of text.

The extents describe a user-space rectangle that encloses the "inked" portion of the text drawn at the origin (0,0) (as it would be drawn by Context::show_text() if the cairo graphics state were set to the same font_face, font_matrix, ctm, and font_options as the ScaledFont object). Additionally, the x_advance and y_advance values indicate the amount by which the current point would be advanced by Context::show_text().

Note that whitespace characters do not directly contribute to the size of the rectangle (extents.width and extents.height). They do contribute indirectly by changing the position of non-whitespace characters. In particular, trailing whitespace characters are likely to not affect the size of the rectangle, though they will affect the x_advance and y_advance values.

Parameters:
utf8 a string of text, encoded in UTF-8
extents Returns the extents of the given string
Since:
1.2


Member Data Documentation

The underlying C cairo object that is wrapped by this ScaledFont.

Referenced by cobj().


The documentation for this class was generated from the following file:

Generated on Thu Sep 4 21:57:17 2008 for cairomm by  doxygen 1.5.5