TrueType fonts renderer. More...

#include <TrueTypeFont.hpp>

Inheritance diagram for nom::TrueTypeFont:

Public Types
typedef TrueTypeFont	self_type
typedef self_type *	RawPtr
typedef std::shared_ptr< self_type >	SharedPtr
Public Types inherited from nom::IFont
enum	FontType { NotDefined = 0 , BitmapFont , TrueTypeFont , BMFont }
typedef IFont	self_type
typedef self_type *	raw_ptr
typedef std::shared_ptr< self_type >	shared_ptr
typedef std::unique_ptr< self_type >	unique_ptr

Public Member Functions
	TrueTypeFont (void)
	Default constructor; initialize the object to sane defaults.
	~TrueTypeFont (void)
	Destructor.
	TrueTypeFont (const TrueTypeFont &copy)
	Copy constructor.
IFont::raw_ptr	clone (void) const override
	Construct a clone of the existing instance.
bool	valid (void) const override
	Validity check.
enum IFont::FontType	type (void) const override
TTF_Font *	font (void) const
const Image *	image (uint32 character_size) const override
sint	spacing (uint32 character_size) const override
	Obtain text character spacing width in pixels.
int	point_size () const
int	newline (uint32 character_size) const override
	Obtain font's line spacing.
int	kerning (uint32 first_char, uint32 second_char, uint32 character_size) const override
	Obtain the kerning pair offsets between two glyphs.
int	hinting (void) const override
	Get the font's hinting style.
const Glyph &	glyph (uint32 codepoint, uint32 character_size) const override
	Obtain a glyph.
int	outline (void)
	Obtain font's outline size.
uint32	font_style (void) const override
	Get the rendering style of the font.
bool	set_point_size (int point_size) override
	Set a new font point size.
bool	set_hinting (int type) override
	Set the requested font hinting style.
bool	set_outline (int outline) override
	Set font's outline size.
void	set_font_style (uint32 style) override
	Set the rendering style of the font.
void	set_font_kerning (bool state) override
	Set the use of kerning for the font.
bool	load (const std::string &filename) override
	Load a new TrueType font from a file.
const FontMetrics &	metrics (void) const override
	Obtain information about the loaded font.

Private Member Functions
bool	build (uint32 character_size)
	Trigger a rebuild of the font metrics from the current font; this recalculates character sizes, coordinate origins, spacing, etc.
const GlyphPage &	pages (void) const
sint	sheet_width (void) const
sint	sheet_height (void) const
const IntRect	glyph_rect (FontPage &page, int width, int height) const
	Find a suitable rectangle within the texture for a glyph.

Private Attributes
enum IFont::FontType	type_
	The type of font we are.
sint	sheet_width_
	Width – in pixels – of overall texture atlas sheet.
sint	sheet_height_
	Height – in pixels – of overall texture atlas sheet.
std::shared_ptr< TTF_Font >	font_
	Font file data, used by SDL_ttf extension.
GlyphPage	pages_
FontMetrics	metrics_
	General font metric data, such as the proper value for newline spacing.
std::string	filename_
sint	point_size_
bool	use_kerning_
	Whether or not to use font kerning.

Detailed Description

TrueType fonts renderer.

[TO BE WRITTEN]

const int MAX_POINT_SIZE = 41;
 
nom::TrueTypeFont font;
 
// We must first load the font into memory from a file.
 
// Cache the glyphs of the font's point size range that we plan on using;
// offloads the cost of re-generating the glyph cache when the end-user
// requests an increase or decrease. (An increase in load-time for a
// decrease in latency upon rescaling, which is especially noticeable on
// older platforms and mobile devices).
for( auto idx = 0; idx != MAX_FONT_POINT_SIZE; ++idx )
{
  font.set_point_size( idx + 1 );
}

See also: http://www.libsdl.org/projects/SDL_ttf/docs/SDL_ttf_toc.html#SEC_Contents; http://freetype.sourceforge.net/freetype2/docs/tutorial/step2.html; http://chanae.walon.org/pub/ttf/ttf_glyphs.htm; http://cboard.cprogramming.com/game-programming/148396-ttf_font-gl-display-list-kerning-issue.html; SFML's sf::Font class

Definition at line 57 of file TrueTypeFont.hpp.

Member Typedef Documentation

◆ RawPtr

typedef self_type* nom::TrueTypeFont::RawPtr

Definition at line 61 of file TrueTypeFont.hpp.

◆ self_type

typedef TrueTypeFont nom::TrueTypeFont::self_type

Definition at line 60 of file TrueTypeFont.hpp.

◆ SharedPtr

typedef std::shared_ptr<self_type> nom::TrueTypeFont::SharedPtr

Definition at line 62 of file TrueTypeFont.hpp.

Constructor & Destructor Documentation

◆ TrueTypeFont()

nom::TrueTypeFont::TrueTypeFont ( void )

Default constructor; initialize the object to sane defaults.

Remarks: The SDL2_TTF extension must first be initialized; see nom::init.

◆ ~TrueTypeFont()

nom::TrueTypeFont::~TrueTypeFont ( void )

Destructor.

Remarks: The SDL2_TTF extension should be shutdown using nom::quit

Member Function Documentation

◆ build()

bool nom::TrueTypeFont::build ( uint32 character_size )

private

Trigger a rebuild of the font metrics from the current font; this recalculates character sizes, coordinate origins, spacing, etc.

Parameters

character_size Font's point size, in pixels, to build glyphs for.

◆ clone()

IFont::raw_ptr nom::TrueTypeFont::clone ( void ) const

overridevirtual

Construct a clone of the existing instance.

Implements nom::IFont.

◆ font_style()

uint32 nom::TrueTypeFont::font_style ( void ) const

overridevirtual

Get the rendering style of the font.

Returns: style A bit-mask composed of one or more of the following styles: TTF_STYLE_NORMAL, TTF_STYLE_BOLD, TTF_STYLE_ITALIC, TTF_STYLE_UNDERLINE, TTF_STYLE_STRIKETHROUGH.

Implements nom::IFont.

◆ glyph()

const Glyph & nom::TrueTypeFont::glyph	(	uint32	codepoint,
		uint32	character_size ) const

overridevirtual

Obtain a glyph.

Parameters

codepoint	ASCII character to lookup
character_size	Reserved for future implementation

Returns: nom::Glyph structure

Implements nom::IFont.

◆ glyph_rect()

const IntRect nom::TrueTypeFont::glyph_rect	(	FontPage &	page,
		int	width,
		int	height ) const

private

Find a suitable rectangle within the texture for a glyph.

Parameters

page	Page of glyphs to search in
width	Width of the rectangle
height	Height of the rectangle

Returns: Found rectangle within the texture

Remarks: This method makes it possible to store bitmap sheets efficiently

Note: Derived from SFML's sf::Font class – thanks!

◆ hinting()

int nom::TrueTypeFont::hinting ( void ) const

overridevirtual

Get the font's hinting style.

Returns: The hinting type, one of: TTF_HINTING_NORMAL, TTF_HINTING_LIGHT, TTF_HINTING_MONO or TTF_HINTING_NONE.

Remarks: The default hinting is TTF_HINTING_NONE.

Implements nom::IFont.

◆ image()

const Image * nom::TrueTypeFont::image ( uint32 character_size ) const

overridevirtual

Obtain the texture atlas used internally for rendering glyphs from

Remarks: It is assumed that the requested character size is already loaded into memory (using TrueTypeFont::set_point_size).

Implements nom::IFont.

◆ kerning()

int nom::TrueTypeFont::kerning	(	uint32	first_char,
		uint32	second_char,
		uint32	character_size ) const

overridevirtual

Obtain the kerning pair offsets between two glyphs.

Returns: A kerning pair offset value on success, or nom::NOM_INT_MIN on failure, such as if the font in use is invalid. If font kerning is disabled, a value of zero (0) is always returned.

Note: The font's point size affects the kerning pair offsets.

Implements nom::IFont.

◆ load()

bool nom::TrueTypeFont::load ( const std::string & filename )

overridevirtual

Load a new TrueType font from a file.

Remarks: Refer to the SDL_ttf documentation for file formats supported. TTF and FON file formats are known to be supported as of this writing.

Implements nom::IFont.

◆ metrics()

const FontMetrics & nom::TrueTypeFont::metrics ( void ) const

overridevirtual

Obtain information about the loaded font.

Remarks: Implements IFont::metrics.

Implements nom::IFont.

◆ newline()

int nom::TrueTypeFont::newline ( uint32 character_size ) const

overridevirtual

Obtain font's line spacing.

Parameters

character_size Point size in pixels

Returns: Height offset in pixels

Implements nom::IFont.

◆ outline()

int nom::TrueTypeFont::outline ( void )

Obtain font's outline size.

Parameters

character_size The point size to retrieve the outline size for

Returns: Outline size in pixels

◆ set_font_kerning()

void nom::TrueTypeFont::set_font_kerning ( bool state )

overridevirtual

Set the use of kerning for the font.

Implements nom::IFont.

◆ set_font_style()

void nom::TrueTypeFont::set_font_style ( uint32 style )

overridevirtual

Set the rendering style of the font.

Parameters

style A bit-mask composed of one or more of the following styles: TTF_STYLE_BOLD, TTF_STYLE_ITALIC, TTF_STYLE_UNDERLINE, TTF_STYLE_STRIKETHROUGH.

Implements nom::IFont.

◆ set_hinting()

bool nom::TrueTypeFont::set_hinting ( int type )

overridevirtual

Set the requested font hinting style.

Remarks: The hinting type, one of: TTF_HINTING_NORMAL, TTF_HINTING_LIGHT, TTF_HINTING_MONO or TTF_HINTING_NONE.

Note: This method call forces a rebuild of the glyph cache if the input type does not match the last known hinting.

Todo: This feature is broken.

Implements nom::IFont.

◆ set_outline()

bool nom::TrueTypeFont::set_outline ( int outline )

overridevirtual

Set font's outline size.

Parameters

outline The outline size in pixels

Remarks: This is an expensive method call; every glyph must be re-built!

Implements nom::IFont.

◆ set_point_size()

bool nom::TrueTypeFont::set_point_size ( int point_size )

overridevirtual

Set a new font point size.

Parameters

size	Point size in pixels

Remarks: This is a potentially expensive call; if the glyphs for the requested point size has not been stored (generated previously), the generation of the font's ASCII glyph symbols must be done.

Note: For performance critical sections where scaling of the font occurs (think: real-time), you may want to take advantage of the glyph caching feature by making a call to this method for every used point size of the scaling range.

Implements nom::IFont.

◆ spacing()

sint nom::TrueTypeFont::spacing ( uint32 character_size ) const

overridevirtual

Obtain text character spacing width in pixels.

Returns: The width applied when the space carriage is encountered when rendered.

Implements nom::IFont.

◆ type()

enum IFont::FontType nom::TrueTypeFont::type ( void ) const

overridevirtual

Implements nom::IFont.

◆ valid()

bool nom::TrueTypeFont::valid ( void ) const

overridevirtual

Validity check.

Implements nom::IFont.

Member Data Documentation

◆ filename_

std::string nom::TrueTypeFont::filename_

private

Store the file path so we can change font sizes on the fly

Note: Replace with FT_Face face (using FreeType2 library)

Definition at line 249 of file TrueTypeFont.hpp.

◆ font_

std::shared_ptr<TTF_Font> nom::TrueTypeFont::font_

private

Font file data, used by SDL_ttf extension.

Definition at line 235 of file TrueTypeFont.hpp.

◆ metrics_

FontMetrics nom::TrueTypeFont::metrics_

private

General font metric data, such as the proper value for newline spacing.

Definition at line 242 of file TrueTypeFont.hpp.

◆ pages_

GlyphPage nom::TrueTypeFont::pages_

mutableprivate

Table mapping a character size to its page – a texture atlas combined with corresponding glyphs data.

Definition at line 239 of file TrueTypeFont.hpp.

◆ point_size_

sint nom::TrueTypeFont::point_size_

private

Font point size (in pixels)

Note: This instance variable is obsolete with FreeType2; see FT_Face->size->metrics.x_ppem

Definition at line 257 of file TrueTypeFont.hpp.

◆ sheet_height_

sint nom::TrueTypeFont::sheet_height_

private

Height – in pixels – of overall texture atlas sheet.

Definition at line 232 of file TrueTypeFont.hpp.

◆ sheet_width_

sint nom::TrueTypeFont::sheet_width_

private

Width – in pixels – of overall texture atlas sheet.

Definition at line 229 of file TrueTypeFont.hpp.

◆ type_

enum IFont::FontType nom::TrueTypeFont::type_

private

The type of font we are.

Definition at line 226 of file TrueTypeFont.hpp.

◆ use_kerning_

bool nom::TrueTypeFont::use_kerning_

private

Whether or not to use font kerning.

Remarks: Default is true.

Definition at line 262 of file TrueTypeFont.hpp.

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

/home/jeff/Projects/nomlib.git/include/nomlib/graphics/fonts/TrueTypeFont.hpp

Public Types

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Member Typedef Documentation

◆ RawPtr

◆ self_type

◆ SharedPtr

Constructor & Destructor Documentation

◆ TrueTypeFont()

◆ ~TrueTypeFont()

Member Function Documentation

◆ build()

◆ clone()

◆ font_style()

◆ glyph()

◆ glyph_rect()

◆ hinting()

◆ image()

◆ kerning()

◆ load()

◆ metrics()

◆ newline()

◆ outline()

◆ set_font_kerning()

◆ set_font_style()

◆ set_hinting()

◆ set_outline()

◆ set_point_size()

◆ spacing()

◆ type()

◆ valid()

Member Data Documentation

◆ filename_

◆ font_

◆ metrics_

◆ pages_

◆ point_size_

◆ sheet_height_

◆ sheet_width_

◆ type_

◆ use_kerning_