OpenGl_Font Class Reference

Texture font. More...

#include <OpenGl_Font.hxx>

Inheritance diagram for OpenGl_Font:

Data Structures
struct	RectI
struct	Tile
	Simple structure stores tile rectangle. More...

Public Member Functions
	OpenGl_Font (const Handle< Font_FTFont > &theFont, const TCollection_AsciiString &theKey="")
	Main constructor.
virtual	~OpenGl_Font ()
	Destroy object.
virtual void	Release (OpenGl_Context *theCtx) override
	Destroy object - will release GPU memory if any.
virtual Standard_Size	EstimatedDataSize () const override
	Returns estimated GPU memory usage.
const TCollection_AsciiString &	ResourceKey () const
const Handle< Font_FTFont > &	FTFont () const
bool	IsValid () const
bool	WasInitialized () const
	Notice that this method doesn't return initialization success state. Use IsValid() instead.
bool	Init (const Handle< OpenGl_Context > &theCtx)
	Initialize GL resources. FreeType font instance should be already initialized!
float	Ascender () const
float	Descender () const
bool	RenderGlyph (const Handle< OpenGl_Context > &theCtx, const Standard_Utf32Char theUChar, Tile &theGlyph)
	Render glyph to texture if not already.
const Handle< OpenGl_Texture > &	Texture () const
Public Member Functions inherited from OpenGl_Resource
	OpenGl_Resource ()
	Empty constructor.
virtual	~OpenGl_Resource ()
	Destructor. Inheritors should call Clean (NULL) within it.
virtual void	DumpJson (Standard_OStream &theOStream, Standard_Integer theDepth=-1) const
	Dumps the content of me into the stream.
Public Member Functions inherited from Standard_Transient
	Standard_Transient ()
	Empty constructor.
	Standard_Transient (const Standard_Transient &)
	Copy constructor – does nothing.
Standard_Transient &	operator= (const Standard_Transient &)
	Assignment operator, needed to avoid copying reference counter.
virtual	~Standard_Transient ()
	Destructor must be virtual.
virtual const opencascade::handle< Standard_Type > &	DynamicType () const
	Returns a type descriptor about this object.
Standard_Boolean	IsInstance (const opencascade::handle< Standard_Type > &theType) const
	Returns a true value if this is an instance of Type.
Standard_Boolean	IsInstance (const Standard_CString theTypeName) const
	Returns a true value if this is an instance of TypeName.
Standard_Boolean	IsKind (const opencascade::handle< Standard_Type > &theType) const
	Returns true if this is an instance of Type or an instance of any class that inherits from Type. Note that multiple inheritance is not supported by OCCT RTTI mechanism.
Standard_Boolean	IsKind (const Standard_CString theTypeName) const
	Returns true if this is an instance of TypeName or an instance of any class that inherits from TypeName. Note that multiple inheritance is not supported by OCCT RTTI mechanism.
Standard_Transient *	This () const
	Returns non-const pointer to this object (like const_cast). For protection against creating handle to objects allocated in stack or call from constructor, it will raise exception Standard_ProgramError if reference counter is zero.
Standard_Integer	GetRefCount () const noexcept
	Get the reference counter of this object.
void	IncrementRefCounter () noexcept
	Increments the reference counter of this object.
Standard_Integer	DecrementRefCounter () noexcept
	Decrements the reference counter of this object; returns the decremented value.
virtual void	Delete () const
	Memory deallocator for transient classes.

Protected Member Functions
bool	renderGlyph (const Handle< OpenGl_Context > &theCtx, const Standard_Utf32Char theChar)
	Render new glyph to the texture.
bool	createTexture (const Handle< OpenGl_Context > &theCtx)
	Allocate new texture.

Protected Attributes
TCollection_AsciiString	myKey
	key of shared resource
Handle< Font_FTFont >	myFont
	FreeType font instance.
Standard_ShortReal	myAscender
	ascender provided my FT font
Standard_ShortReal	myDescender
	descender provided my FT font
Standard_Integer	myTileSizeY
	tile height
Standard_Integer	myLastTileId
	id of last tile
RectI	myLastTilePx
Standard_Integer	myTextureFormat
	texture format
NCollection_Vector< Handle< OpenGl_Texture > >	myTextures
	array of textures
NCollection_Vector< Tile >	myTiles
	array of loaded tiles
NCollection_DataMap< Standard_Utf32Char, Standard_Integer >	myGlyphMap

Additional Inherited Members
Public Types inherited from Standard_Transient
typedef void	base_type
	Returns a type descriptor about this object.
Static Public Member Functions inherited from Standard_Transient
static constexpr const char *	get_type_name ()
	Returns a type descriptor about this object.
static const opencascade::handle< Standard_Type > &	get_type_descriptor ()
	Returns type descriptor of Standard_Transient class.

Detailed Description

Texture font.

Constructor & Destructor Documentation

OpenGl_Font()

OpenGl_Font::OpenGl_Font	(	const Handle< Font_FTFont > &	theFont,
		const TCollection_AsciiString &	theKey = "" )

Main constructor.

~OpenGl_Font()

virtual OpenGl_Font::~OpenGl_Font ( )

virtual

Destroy object.

Member Function Documentation

Ascender()

float OpenGl_Font::Ascender ( ) const

inline

Returns

vertical distance from the horizontal baseline to the highest character coordinate

createTexture()

bool OpenGl_Font::createTexture ( const Handle< OpenGl_Context > & theCtx )

protected

Allocate new texture.

Descender()

float OpenGl_Font::Descender ( ) const

inline

Returns

vertical distance from the horizontal baseline to the lowest character coordinate

EstimatedDataSize()

virtual Standard_Size OpenGl_Font::EstimatedDataSize ( ) const

overridevirtual

Returns estimated GPU memory usage.

Implements OpenGl_Resource.

FTFont()

const Handle< Font_FTFont > & OpenGl_Font::FTFont ( ) const

inline

Returns

FreeType font instance specified on construction.

Init()

bool OpenGl_Font::Init

(

const Handle< OpenGl_Context > &

theCtx

)

Initialize GL resources. FreeType font instance should be already initialized!

IsValid()

bool OpenGl_Font::IsValid ( ) const

inline

Returns

true if font was loaded successfully.

Release()

virtual void OpenGl_Font::Release ( OpenGl_Context * theCtx )

overridevirtual

Destroy object - will release GPU memory if any.

Implements OpenGl_Resource.

RenderGlyph()

bool OpenGl_Font::RenderGlyph	(	const Handle< OpenGl_Context > &	theCtx,
		const Standard_Utf32Char	theUChar,
		Tile &	theGlyph )

Render glyph to texture if not already.

Parameters

theCtx	active context
theUChar	unicode symbol to render
theGlyph	computed glyph position rectangle, texture ID and UV coordinates

renderGlyph()

bool OpenGl_Font::renderGlyph ( const Handle< OpenGl_Context > & theCtx, const Standard_Utf32Char theChar )

protected

Render new glyph to the texture.

ResourceKey()

const TCollection_AsciiString & OpenGl_Font::ResourceKey ( ) const

inline

Returns

key of shared resource

Texture()

const Handle< OpenGl_Texture > & OpenGl_Font::Texture ( ) const

inline

Returns

first texture.

WasInitialized()

bool OpenGl_Font::WasInitialized ( ) const

inline

Notice that this method doesn't return initialization success state. Use IsValid() instead.

Returns

true if initialization was already called.

Field Documentation

myAscender

Standard_ShortReal OpenGl_Font::myAscender

protected

ascender provided my FT font

myDescender

Standard_ShortReal OpenGl_Font::myDescender

protected

descender provided my FT font

myFont

Handle< Font_FTFont > OpenGl_Font::myFont

protected

FreeType font instance.

myGlyphMap

NCollection_DataMap<Standard_Utf32Char, Standard_Integer> OpenGl_Font::myGlyphMap

protected

myKey

TCollection_AsciiString OpenGl_Font::myKey

protected

key of shared resource

myLastTileId

Standard_Integer OpenGl_Font::myLastTileId

protected

id of last tile

myLastTilePx

RectI OpenGl_Font::myLastTilePx

protected

myTextureFormat

Standard_Integer OpenGl_Font::myTextureFormat

protected

texture format

myTextures

NCollection_Vector< Handle< OpenGl_Texture > > OpenGl_Font::myTextures

protected

array of textures

myTiles

NCollection_Vector<Tile> OpenGl_Font::myTiles

protected

array of loaded tiles

myTileSizeY

Standard_Integer OpenGl_Font::myTileSizeY

protected

tile height

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

• OpenGl_Font.hxx