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Pango::LayoutLine Class Reference

A Pango::LayoutLine represents one of the lines resulting from laying out a paragraph via Pango::Layout. More...

List of all members.

Public Member Functions

void reference () const
void unreference () const
PangoLayoutLine* gobj ()
 Provides access to the underlying C instance.
const PangoLayoutLine* gobj () const
 Provides access to the underlying C instance.
PangoLayoutLine* gobj_copy () const
 Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.
bool x_to_index (int x_pos, int& index, int& trailing) const
 Converts from x offset to the byte index of the corresponding character within the text of the layout.
int index_to_x (int index, bool trailing) const
 Converts an index within a line to a x position.
Glib::ArrayHandle< std::pair
< int, int > > 
get_x_ranges (int start_index, int end_index) const
 Get a list of visual ranges corresponding to a given logical range.
void get_extents (Rectangle& ink_rect, Rectangle& logical_rect) const
 Compute the logical and ink extents of a layout line.
Rectangle get_ink_extents () const
 Compute the ink extents of a layout line.
Rectangle get_logical_extents () const
 Compute the logical extents of a layout line.
void get_pixel_extents (Rectangle& ink_rect, Rectangle& logical_rect) const
 Compute the logical and ink extents of a layout line.
Rectangle get_pixel_ink_extents () const
 Compute the ink extents of a layout line in device units.
Rectangle get_pixel_logical_extents () const
 Compute the logical extents of a layout line in device units.
void show_in_cairo_context (const Cairo::RefPtr< Cairo::Context >& context)
 Draws this LayoutLine in the specified Cairo context.
void add_to_cairo_context (const Cairo::RefPtr< Cairo::Context >& context)
 Adds the text in this LayoutLine to the current path in the specified Cairo context.
Glib::RefPtr< Pango::Layoutget_layout ()
Glib::RefPtr< const Pango::Layoutget_layout () const
int get_length () const
int get_start_index () const

Protected Member Functions

 LayoutLine ()
void operator delete (void*, size_t)

Related Functions

(Note that these are not member functions.)

Glib::RefPtr< Pango::LayoutLinewrap (PangoLayoutLine* object, bool take_copy=false)
 A Glib::wrap() method for this object.


Detailed Description

A Pango::LayoutLine represents one of the lines resulting from laying out a paragraph via Pango::Layout.

Pango::LayoutLine objects are obtained by calling Pango::Layout::get_line() and are only valid until the text, attributes, or settings of the parent Pango::Layout are modified. Routines for rendering Pango::Layout objects are provided in code specific to each rendering system.


Constructor& Destructor Documentation

Pango::LayoutLine::LayoutLine (  )  [protected]


Member Function Documentation

void Pango::LayoutLine::reference (  )  const

void Pango::LayoutLine::unreference (  )  const

PangoLayoutLine* Pango::LayoutLine::gobj (  ) 

Provides access to the underlying C instance.

const PangoLayoutLine* Pango::LayoutLine::gobj (  )  const

Provides access to the underlying C instance.

PangoLayoutLine* Pango::LayoutLine::gobj_copy (  )  const

Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.

void Pango::LayoutLine::operator delete ( void *  ,
size_t   
) [protected]

bool Pango::LayoutLine::x_to_index ( int  x_pos,
int &  index,
int &  trailing 
) const

Converts from x offset to the byte index of the corresponding character within the text of the layout.

If x_pos is outside the line, index and trailing will point to the very first or very last position in the line. This determination is based on the resolved direction of the paragraph; for example, if the resolved direction is right-to-left, then an X position to the right of the line (after it) results in 0 being stored in index and trailing. An X position to the left of the line results in index pointing to the (logical) last grapheme in the line and trailing being set to the number of characters in that grapheme. The reverse is true for a left-to-right line.

Parameters:
x_pos The X offset (in Pango units) from the left edge of the line.
index Location to store calculated byte index for the grapheme in which the user clicked.
trailing Location to store an integer indicating where in the grapheme the user clicked. It will either be zero, or the number of characters in the grapheme. 0 represents the leading edge of the grapheme.
Returns:
false if x_pos was outside the line, true if inside.

int Pango::LayoutLine::index_to_x ( int  index,
bool  trailing 
) const

Converts an index within a line to a x position.

Parameters:
index Byte offset of a grapheme within the layout.
trailing A boolean indicating the edge of the grapheme to retrieve the position of. If false, the trailing edge of the grapheme, if true the leading of the grapheme.
Returns:
The x offset (in thousands of a device unit).

Glib::ArrayHandle<std::pair<int,int> > Pango::LayoutLine::get_x_ranges ( int  start_index,
int  end_index 
) const

Get a list of visual ranges corresponding to a given logical range.

This list is not necessarily minimal - there may be consecutive ranges which are adjacent. The ranges will be sorted from left to right. The ranges are with respect to the left edge of the entire layout, not with respect to the line.

Parameters:
start_index The start byte index of the logical range. If the value of start_index is less than the start index for the line, then the first range will extend all the way to the leading edge of the layout. Otherwise it will start at the leading edge of the first character.
end_index The end byte index of the logical range. If the value of end_index is greater than the end index for the line, then the last range will extend all the way to the trailing edge of the layout. Otherwise, it will end at the trailing edge of the last character.
Returns:
An array of ranges represented by pairs of integers marking the start and end pixel coordinates of the ranges.

void Pango::LayoutLine::get_extents ( Rectangle ink_rect,
Rectangle logical_rect 
) const

Compute the logical and ink extents of a layout line.

See the documentation for Pango::Font::get_glyph_extents() for details about the interpretation of the rectangles.

Parameters:
ink_rect Rectangle used to store the extents of the glyph string as drawn.
logical_rect Rectangle used to store the logical extents of the glyph string.

Rectangle Pango::LayoutLine::get_ink_extents (  )  const

Compute the ink extents of a layout line.

Returns:
The extents of the layout line as drawn.

Rectangle Pango::LayoutLine::get_logical_extents (  )  const

Compute the logical extents of a layout line.

Returns:
The logical extents of the layout line.

void Pango::LayoutLine::get_pixel_extents ( Rectangle ink_rect,
Rectangle logical_rect 
) const

Compute the logical and ink extents of a layout line.

See the documentation for Pango::Font::get_glyph_extents() for details about the interpretation of the rectangles. The returned rectangles are in device units, as opposed to pango_layout_line_get_extents(), which returns the extents in units of device unit / PANGO_SCALE.

Parameters:
ink_rect Rectangle used to store the extents of the glyph string as drawn.
logical_rect Rectangle used to store the logical extents of the glyph string.

Rectangle Pango::LayoutLine::get_pixel_ink_extents (  )  const

Compute the ink extents of a layout line in device units.

Returns:
The extents of the layout line as drawn.

Rectangle Pango::LayoutLine::get_pixel_logical_extents (  )  const

Compute the logical extents of a layout line in device units.

Returns:
The logical extents of the layout line.

void Pango::LayoutLine::show_in_cairo_context ( const Cairo::RefPtr< Cairo::Context > &  context  ) 

Draws this LayoutLine in the specified Cairo context.

The origin of the glyphs (the left edge of the line) will be drawn at the current point of the cairo context.

Parameters:
context A Cairo context.

void Pango::LayoutLine::add_to_cairo_context ( const Cairo::RefPtr< Cairo::Context > &  context  ) 

Adds the text in this LayoutLine to the current path in the specified Cairo context.

The origin of the glyphs (the left edge of the line) will be at the current point of the cairo context.

Parameters:
context A Cairo context.

Glib::RefPtr<Pango::Layout> Pango::LayoutLine::get_layout (  ) 

Glib::RefPtr<const Pango::Layout> Pango::LayoutLine::get_layout (  )  const

int Pango::LayoutLine::get_length (  )  const

int Pango::LayoutLine::get_start_index (  )  const


Friends And Related Function Documentation

Glib::RefPtr< Pango::LayoutLine > wrap ( PangoLayoutLine *  object,
bool  take_copy = false 
) [related]

A Glib::wrap() method for this object.

Parameters:
object The C instance.
take_copy False if the result should take ownership of the C instance. True if it should take a new copy or ref.
Returns:
A C++ instance that wraps this C instance.


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

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