Font is a base class for implementation-specific representations of fonts. More...

#include "font.h"

Inheritance diagram for ion::text::Font:

Collaboration diagram for ion::text::Font:

Classes
struct	FontMetrics
	This struct represents the cumulative metrics for the font. More...

struct	GlyphGrid
	A grid representing a rendered glyph, with each grid pixel representing pixel coverage in the range (0,1). More...

Public Member Functions
const std::string &	GetName () const
	Returns the name of the font. More...

size_t	GetSizeInPixels () const
	Returns the size of the font in pixels. More...

size_t	GetSdfPadding () const
	Returns the padding value used when generating SDF glyphs from the font. More...

const FontMetrics &	GetFontMetrics () const
	Returns the FontMetrics for the font. More...

const GlyphGrid &	GetGlyphGrid (GlyphIndex glyph_index) const
	Returns the GlyphGrid for the indexed character. More...

void	FilterGlyphs (GlyphSet *glyph_set)
	Filter zero-size glyphs from `glyph_set`. More...

virtual GlyphIndex	GetDefaultGlyphForChar (CharIndex char_index) const =0
	Returns the index of a glyph corresponding to the given character in the default ("unicode", in practice) charmap of the font. More...

void	AddGlyphsForAsciiCharacterRange (ion::text::CharIndex start, ion::text::CharIndex finish, ion::text::GlyphSet *glyphs)
	For each character in [start,finish] adds the default glyph from `font` to `glyphs`. More...

virtual const Layout	BuildLayout (const std::string &text, const LayoutOptions &options) const =0
	Creates a layout as specified by `options` for a given single- or multi- line string `text`. More...

void	CacheSdfGrids (const GlyphSet &glyph_set)
	Makes sure that the GlyphData for each glyph in glyph_set has an SDF grid cached inside the font. More...

virtual void	AddFallbackFont (const FontPtr &fallback)=0
	Causes this font to use the font `fallback` as a fallback if a requested glyph is not found. More...

const AllocatorPtr &	GetAllocator () const
	Returns the Allocator that was used for the instance. More...

const AllocatorPtr &	GetNonNullAllocator () const
	Return our allocator, or the default allocator if the instance was declared on the stack. More...

const AllocatorPtr &	GetAllocatorForLifetime (AllocationLifetime lifetime) const
	Convenience function that returns the Allocator to use to allocate an object with a specific lifetime. More...

void *	operator new (size_t size)
	The standard no-parameter new operator uses the default Allocator. More...

void *	operator new (size_t size, AllocationLifetime lifetime)
	This overloaded version of the new operator uses the AllocationManager's default Allocator for the specified lifetime. More...

void *	operator new (size_t size, const AllocatorPtr &allocator)
	This overloaded version of the new operator takes the Allocator to use directly as a parameter. More...

void *	operator new (size_t size, const AllocatorPtr &allocator, void *ptr)
	Special operator new for using placement new with Allocatables. More...

void *	operator new (size_t size, void *ptr)
	The placement new operator is defined conventionally. More...

void	operator delete (void *ptr)
	Define the delete operator to use specialized functions dealing with an Allocator. More...

void	operator delete (void *ptr, AllocationLifetime lifetime)
	Windows requires these (or it issues C4291 warnings). More...

void	operator delete (void *ptr, const AllocatorPtr &allocator)

void	operator delete (void ptr, void ptr2)
	The placement delete operator does nothing, as usual. More...

int	GetRefCount () const
	GetRefCount() is part of the interface necessary for SharedPtr. More...

Protected Types
typedef base::AllocMap < GlyphIndex, GlyphGrid >	GlyphMap
	Convenience typedef for the map storing GlyphGrid instances. More...

Protected Member Functions
	Font (const std::string &name, size_t size_in_pixels, size_t sdf_padding)
	The constructor is protected because this is an abstract base class. More...

	~Font () override
	The destructor is protected because all base::Referent classes must have protected or private destructors. More...

GlyphGrid *	GetMutableGlyphGrid (GlyphIndex glyph_index) const
	Non-const version of GetGlyphGrid. More...

GlyphGrid *	GetMutableGlyphGridLocked (GlyphIndex glyph_index) const
	Prelocked version of GetMutableGlyphGrid. More...

virtual bool	LoadGlyphGrid (GlyphIndex glyph_index, GlyphGrid *glyph_grid) const
	Called by GetGlyphGrid() for missing glyphs. More...

const GlyphGrid &	AddGlyph (GlyphIndex glyph_index, const GlyphGrid &glyph) const
	Adds a GlyphGrid to the GlyphMap. More...

void	SetFontMetrics (const FontMetrics &metrics)
	Sets FontMetrics. SetFontMetrics() should only ever be called once. More...

bool	CacheSdfGrid (GlyphIndex glyph_index, const base::Array2< double > &sdf_pixels)
	Replaces the grid in a glyph with an SDF grid. More...

Protected Attributes
const size_t	size_in_pixels_
	Size in pixels. More...

Detailed Description

Font is a base class for implementation-specific representations of fonts.

It contains font metrics, glyph metrics, and rendered glyph grids.

Definition at line 43 of file font.h.

Member Typedef Documentation

typedef base::AllocMap<GlyphIndex, GlyphGrid> ion::text::Font::GlyphMap

protected

Convenience typedef for the map storing GlyphGrid instances.

Definition at line 134 of file font.h.

Constructor & Destructor Documentation

ion::text::Font::Font	(	const std::string &	name,
		size_t	size_in_pixels,
		size_t	sdf_padding
	)

protected

The constructor is protected because this is an abstract base class.

Definition at line 41 of file font.cc.

ion::text::Font::~Font ( )

overrideprotected

The destructor is protected because all base::Referent classes must have protected or private destructors.

Definition at line 47 of file font.cc.

Member Function Documentation

virtual void ion::text::Font::AddFallbackFont ( const FontPtr & fallback )

pure virtual

Causes this font to use the font fallback as a fallback if a requested glyph is not found.

This is useful in internationalization cases, as few fonts contain glyphs for enough unicode codepoints to satisfy most languages.

Implemented in ion::text::FreeTypeFont, and ion::text::CoreTextFont.

const Font::GlyphGrid & ion::text::Font::AddGlyph	(	GlyphIndex	glyph_index,
		const GlyphGrid &	glyph
	)		const

protected

Adds a GlyphGrid to the GlyphMap.

Definition at line 81 of file font.cc.

References ion::base::IsInvalidReference().

void ion::text::Font::AddGlyphsForAsciiCharacterRange	(	ion::text::CharIndex	start,
		ion::text::CharIndex	finish,
		ion::text::GlyphSet *	glyphs
	)

For each character in [start,finish] adds the default glyph from font to glyphs.

Since this is not well-defined for all of Unicode, enforces that [start,finish] lies within [1,127], where the character->glyph mapping is simple enough.

Definition at line 137 of file font.cc.

References DCHECK_GE, DCHECK_LE, and GetDefaultGlyphForChar().

virtual const Layout ion::text::Font::BuildLayout	(	const std::string &	text,
		const LayoutOptions &	options
	)		const

pure virtual

Creates a layout as specified by options for a given single- or multi- line string text.

Implemented in ion::text::FreeTypeFont, and ion::text::CoreTextFont.

bool ion::text::Font::CacheSdfGrid	(	GlyphIndex	glyph_index,
		const base::Array2< double > &	sdf_pixels
	)

protected

Replaces the grid in a glyph with an SDF grid.

This is used to cache the SDF grid, since it is relatively expensive to compute. Logs an error and returns false on error.

Definition at line 110 of file font.cc.

References ion::port::ERROR, GetMutableGlyphGrid(), ion::text::Font::GlyphGrid::is_sdf, LOG, and ion::text::Font::GlyphGrid::pixels.

Referenced by CacheSdfGrids().

void ion::text::Font::CacheSdfGrids ( const GlyphSet & glyph_set )

Makes sure that the GlyphData for each glyph in glyph_set has an SDF grid cached inside the font.

This assumes that the requested glyphs are available in the font. There is no real need to call this outside of Ion's internal code.

Definition at line 95 of file font.cc.

References CacheSdfGrid(), ion::text::ComputeSdfGrid(), DCHECK, GetMutableGlyphGrid(), GetSdfPadding(), ion::text::Font::GlyphGrid::is_sdf, ion::base::IsInvalidReference(), and ion::text::Font::GlyphGrid::pixels.

void ion::text::Font::FilterGlyphs ( GlyphSet * glyph_set )

Filter zero-size glyphs from glyph_set.

Definition at line 125 of file font.cc.

References GetMutableGlyphGridLocked(), and ion::text::Font::GlyphGrid::IsZeroSize().

const AllocatorPtr& ion::base::Allocatable::GetAllocator ( ) const

inlineinherited

Returns the Allocator that was used for the instance.

This will be NULL if the instance was declared on the stack or created with normal placement new.

Definition at line 68 of file allocatable.h.

References allocator_.

Referenced by ion::base::DataContainer::CreateAndCopy(), ion::text::DynamicFontImage::FindContainingImageDataIndex(), and ion::text::DynamicFontImage::FindImageDataIndex().

const AllocatorPtr& ion::base::Allocatable::GetAllocatorForLifetime ( AllocationLifetime lifetime ) const

inlineinherited

Convenience function that returns the Allocator to use to allocate an object with a specific lifetime.

Definition at line 78 of file allocatable.h.

References ion::base::Allocator::GetAllocatorForLifetime().

Referenced by ion::text::BasicBuilder::BuildVertexData(), ion::text::OutlineBuilder::BuildVertexData(), ion::gfxutils::ShaderManager::CreateShaderProgram(), ion::text::DynamicFontImage::FindContainingImageDataIndex(), ion::text::DynamicFontImage::FindImageDataIndex(), ion::gfx::Renderer::Renderer(), and ion::gfx::UpdateStateTable().

virtual GlyphIndex ion::text::Font::GetDefaultGlyphForChar ( CharIndex char_index ) const

pure virtual

Returns the index of a glyph corresponding to the given character in the default ("unicode", in practice) charmap of the font.

Note that this is an ill-defined concept, as a character may well require multiple glyphs to render, or require different glyphs in different contexts, and so on. This and AddGlyphsForAsciiCharacterRange are therefore intended as a quick and dirty way to prepopulate a font with glyps so that a static FontImage can be used, and cannot be assumed to work on non-trivial (i.e., non-latin) characters. Returns zero if no glyph available.

Implemented in ion::text::FreeTypeFont, and ion::text::CoreTextFont.

Referenced by AddGlyphsForAsciiCharacterRange().

const FontMetrics& ion::text::Font::GetFontMetrics ( ) const

inline

Returns the FontMetrics for the font.

Definition at line 87 of file font.h.

Referenced by ion::text::ComputeTextSize().

const Font::GlyphGrid & ion::text::Font::GetGlyphGrid ( GlyphIndex glyph_index ) const

Returns the GlyphGrid for the indexed character.

Returns an invalid reference if the index does not refer to a glyph in the font.

Definition at line 49 of file font.cc.

References GetMutableGlyphGrid().

Font::GlyphGrid * ion::text::Font::GetMutableGlyphGrid ( GlyphIndex glyph_index ) const

protected

Non-const version of GetGlyphGrid.

Definition at line 55 of file font.cc.

References GetMutableGlyphGridLocked().

Referenced by CacheSdfGrid(), CacheSdfGrids(), and GetGlyphGrid().

Font::GlyphGrid * ion::text::Font::GetMutableGlyphGridLocked ( GlyphIndex glyph_index ) const

protected

Prelocked version of GetMutableGlyphGrid.

Definition at line 60 of file font.cc.

References DCHECK, ion::port::Mutex::IsLocked(), and LoadGlyphGrid().

Referenced by FilterGlyphs(), and GetMutableGlyphGrid().

const std::string& ion::text::Font::GetName ( ) const

inline

Returns the name of the font.

Definition at line 75 of file font.h.

const AllocatorPtr& ion::base::Allocatable::GetNonNullAllocator ( ) const

inlineinherited

Return our allocator, or the default allocator if the instance was declared on the stack.

Definition at line 72 of file allocatable.h.

References allocator_, and ion::base::AllocationManager::GetNonNullAllocator().

int ion::base::Shareable::GetRefCount ( ) const

inlineinherited

GetRefCount() is part of the interface necessary for SharedPtr.

Definition at line 34 of file shareable.h.

Referenced by ion::base::Notifier::RemoveReceiver().

size_t ion::text::Font::GetSdfPadding ( ) const

inline

Returns the padding value used when generating SDF glyphs from the font.

Most SDF glyphs are larger than the original glyph so that the outer edges have a nice distance fall-off. The SDF glyph grids are padded by this many pixels on all sides.

Definition at line 84 of file font.h.

Referenced by CacheSdfGrids(), ion::text::BasicBuilder::UpdateUniforms(), and ion::text::OutlineBuilder::UpdateUniforms().

size_t ion::text::Font::GetSizeInPixels ( ) const

inline

Returns the size of the font in pixels.

Definition at line 78 of file font.h.

Referenced by ion::text::ComputeTextSize().

bool ion::text::Font::LoadGlyphGrid	(	GlyphIndex	glyph_index,
		GlyphGrid *	glyph_grid
	)		const

protectedvirtual

Called by GetGlyphGrid() for missing glyphs.

Child classes that load glyphs on-demand should override this method to load the result into glyph_grid. Returns true if a glyph was loaded.

Reimplemented in ion::text::FreeTypeFont, and ion::text::CoreTextFont.

Definition at line 77 of file font.cc.

Referenced by GetMutableGlyphGridLocked().

void ion::base::Allocatable::operator delete ( void * ptr )

inlineinherited

Define the delete operator to use specialized functions dealing with an Allocator.

Definition at line 109 of file allocatable.h.

void ion::base::Allocatable::operator delete	(	void *	ptr,
		AllocationLifetime	lifetime
	)

inlineinherited

Windows requires these (or it issues C4291 warnings).

Definition at line 112 of file allocatable.h.

void ion::base::Allocatable::operator delete	(	void *	ptr,
		const AllocatorPtr &	allocator
	)

inlineinherited

Definition at line 113 of file allocatable.h.

void ion::base::Allocatable::operator delete	(	void *	ptr,
		void *	ptr2
	)

inlineinherited

The placement delete operator does nothing, as usual.

Definition at line 118 of file allocatable.h.

void* ion::base::Allocatable::operator new ( size_t size )

inlineinherited

The standard no-parameter new operator uses the default Allocator.

Definition at line 84 of file allocatable.h.

void* ion::base::Allocatable::operator new	(	size_t	size,
		AllocationLifetime	lifetime
	)

inlineinherited

This overloaded version of the new operator uses the AllocationManager's default Allocator for the specified lifetime.

Definition at line 88 of file allocatable.h.

void* ion::base::Allocatable::operator new	(	size_t	size,
		const AllocatorPtr &	allocator
	)

inlineinherited

This overloaded version of the new operator takes the Allocator to use directly as a parameter.

If the Allocator pointer is NULL, this uses the default Allocator.

Definition at line 95 of file allocatable.h.

void* ion::base::Allocatable::operator new	(	size_t	size,
		const AllocatorPtr &	allocator,
		void *	ptr
	)

inlineinherited

Special operator new for using placement new with Allocatables.

Definition at line 100 of file allocatable.h.

void* ion::base::Allocatable::operator new	(	size_t	size,
		void *	ptr
	)

inlineinherited

The placement new operator is defined conventionally.

Definition at line 105 of file allocatable.h.

void ion::text::Font::SetFontMetrics ( const FontMetrics & metrics )

protected

Sets FontMetrics. SetFontMetrics() should only ever be called once.

Definition at line 89 of file font.cc.

References DCHECK_EQ, and ion::text::Font::FontMetrics::line_advance_height.

Referenced by ion::text::CoreTextFont::CoreTextFont(), and ion::text::FreeTypeFont::FreeTypeFont().

Member Data Documentation

const size_t ion::text::Font::size_in_pixels_

protected

Size in pixels.

Definition at line 169 of file font.h.

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

text/font.h
text/font.cc

Classes

Public Member Functions

Protected Types

Protected Member Functions

Protected Attributes

Detailed Description

Member Typedef Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation