OpenTTD
TrueTypeFontCache Class Referenceabstract

Font cache for fonts that are based on a TrueType font. More...

Inheritance diagram for TrueTypeFontCache:
FontCache FreeTypeFontCache

Data Structures

struct  GlyphEntry
 Container for information about a glyph. More...
 

Public Member Functions

 TrueTypeFontCache (FontSize fs, int pixels)
 Create a new TrueTypeFontCache. More...
 
virtual ~TrueTypeFontCache ()
 Free everything that was allocated for this font cache.
 
virtual int GetFontSize () const
 Get the nominal font size of the font. More...
 
virtual SpriteID GetUnicodeGlyph (WChar key)
 Get the SpriteID mapped to the given key. More...
 
virtual void SetUnicodeGlyph (WChar key, SpriteID sprite)
 Map a SpriteID to the key. More...
 
virtual void InitializeUnicodeGlyphMap ()
 Initialize the glyph map.
 
virtual const SpriteGetGlyph (GlyphID key)
 Get the glyph (sprite) of the given key. More...
 
virtual const void * GetFontTable (uint32 tag, size_t &length)
 Read a font table from the font. More...
 
virtual void ClearFontCache ()
 Reset cached glyphs.
 
virtual uint GetGlyphWidth (GlyphID key)
 Get the width of the glyph with the given key. More...
 
virtual bool GetDrawGlyphShadow ()
 Do we need to draw a glyph shadow? More...
 
virtual bool IsBuiltInFont ()
 Is this a built-in sprite font?
 
- Public Member Functions inherited from FontCache
 FontCache (FontSize fs)
 Create a new font cache. More...
 
virtual ~FontCache ()
 Clean everything up. More...
 
FontSize GetSize () const
 Get the FontSize of the font. More...
 
virtual int GetHeight () const
 Get the height of the font. More...
 
int GetAscender () const
 Get the ascender value of the font. More...
 
int GetDescender () const
 Get the descender value of the font. More...
 
int GetUnitsPerEM () const
 Get the units per EM value of the font. More...
 
virtual GlyphID MapCharToGlyph (WChar key)=0
 Map a character into a glyph. More...
 
virtual void * GetOSHandle ()
 Get the native OS font handle, if there is one. More...
 
virtual const char * GetFontName ()=0
 Get the name of this font. More...
 
bool HasParent ()
 Check whether the font cache has a parent.
 

Protected Types

typedef SmallMap< uint32, SmallPair< size_t, const void * > > FontTable
 Table with font table cache.
 

Protected Member Functions

GlyphEntryGetGlyphPtr (GlyphID key)
 
void SetGlyphPtr (GlyphID key, const GlyphEntry *glyph, bool duplicate=false)
 
virtual const void * InternalGetFontTable (uint32 tag, size_t &length)=0
 
virtual const SpriteInternalGetGlyph (GlyphID key, bool aa)=0
 

Protected Attributes

int req_size
 Requested font size.
 
int used_size
 Used font size.
 
FontTable font_tables
 Cached font tables.
 
GlyphEntry ** glyph_to_sprite
 The glyph cache. More...
 
- Protected Attributes inherited from FontCache
FontCacheparent
 The parent of this font cache.
 
const FontSize fs
 The size of the font.
 
int height
 The height of the font.
 
int ascender
 The ascender value of the font.
 
int descender
 The descender value of the font.
 
int units_per_em
 The units per EM value of the font.
 

Additional Inherited Members

- Static Public Member Functions inherited from FontCache
static FontCacheGet (FontSize fs)
 Get the font cache of a given font size. More...
 

Detailed Description

Font cache for fonts that are based on a TrueType font.

Definition at line 209 of file fontcache.cpp.

Constructor & Destructor Documentation

◆ TrueTypeFontCache()

TrueTypeFontCache::TrueTypeFontCache ( FontSize  fs,
int  pixels 
)

Create a new TrueTypeFontCache.

Parameters
fsThe font size that is going to be cached.
pixelsThe number of pixels this font should be high.

Definition at line 265 of file fontcache.cpp.

Member Function Documentation

◆ GetDrawGlyphShadow()

bool TrueTypeFontCache::GetDrawGlyphShadow ( )
virtual

Do we need to draw a glyph shadow?

Returns
True if it has to be done, otherwise false.

Implements FontCache.

Definition at line 352 of file fontcache.cpp.

References FontCache::fs, and FS_NORMAL.

◆ GetFontSize()

virtual int TrueTypeFontCache::GetFontSize ( ) const
inlinevirtual

Get the nominal font size of the font.

Returns
The nominal font size.

Reimplemented from FontCache.

Definition at line 248 of file fontcache.cpp.

◆ GetFontTable()

const void * TrueTypeFontCache::GetFontTable ( uint32  tag,
size_t &  length 
)
virtual

Read a font table from the font.

Parameters
tagThe of the table to load.
lengthThe length of the read data.
Returns
The loaded table data.

Implements FontCache.

Definition at line 427 of file fontcache.cpp.

References SmallMap< T, U >::Find(), font_tables, and SmallMap< T, U >::Insert().

◆ GetGlyph()

const Sprite * TrueTypeFontCache::GetGlyph ( GlyphID  key)
virtual

Get the glyph (sprite) of the given key.

Parameters
keyThe key to look up.
Returns
The sprite.

Implements FontCache.

Definition at line 370 of file fontcache.cpp.

◆ GetGlyphWidth()

uint TrueTypeFontCache::GetGlyphWidth ( GlyphID  key)
virtual

Get the width of the glyph with the given key.

Parameters
keyThe key to look up.
Returns
The width.

Implements FontCache.

Definition at line 357 of file fontcache.cpp.

◆ GetUnicodeGlyph()

virtual SpriteID TrueTypeFontCache::GetUnicodeGlyph ( WChar  key)
inlinevirtual

Get the SpriteID mapped to the given key.

Parameters
keyThe key to get the sprite for.
Returns
The sprite.

Implements FontCache.

Definition at line 249 of file fontcache.cpp.

References FontCache::GetUnicodeGlyph(), and FontCache::parent.

◆ SetUnicodeGlyph()

virtual void TrueTypeFontCache::SetUnicodeGlyph ( WChar  key,
SpriteID  sprite 
)
inlinevirtual

Map a SpriteID to the key.

Parameters
keyThe key to map to.
spriteThe sprite that is being mapped.

Implements FontCache.

Definition at line 250 of file fontcache.cpp.

References FontCache::parent, and FontCache::SetUnicodeGlyph().

Field Documentation

◆ glyph_to_sprite

GlyphEntry** TrueTypeFontCache::glyph_to_sprite
protected

The glyph cache.

This is structured to reduce memory consumption. 1) There is a 'segment' table for each font size. 2) Each segment table is a discrete block of characters. 3) Each block contains 256 (aligned) characters sequential characters.

The cache is accessed in the following way: For character 0x0041 ('A'): glyph_to_sprite[0x00][0x41] For character 0x20AC (Euro): glyph_to_sprite[0x20][0xAC]

Currently only 256 segments are allocated, "limiting" us to 65536 characters. This can be simply changed in the two functions Get & SetGlyphPtr.

Definition at line 237 of file fontcache.cpp.

Referenced by ClearFontCache().


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