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FSlateFontCache

Font caching implementation Caches characters into textures as needed

API > API/Runtime > API/Runtime/SlateCore

Font caching implementation Caches characters into textures as needed

   
Name FSlateFontCache
Type class
Header File /Engine/Source/Runtime/SlateCore/Public/Fonts/FontCache.h
Include Path #include "Fonts/FontCache.h"

Syntax

class FSlateFontCache :  
    public ISlateAtlasProvider ,  
    public FSlateFlushableAtlasCache

Inheritance Hierarchy

Implements Interfaces

Constructors

Name Remarks Include Path Unreal Specifiers
Constructor Fonts/FontCache.h  
Non-copyable. Fonts/FontCache.h  

Destructors

Name Remarks Include Path Unreal Specifiers

virtual ~FSlateFontCache()

   Fonts/FontCache.h  

Variables

Protected

Name Type Remarks Include Path Unreal Specifiers
AllFontTextures TArray< TSharedRef< ISlateFontTexture > > Array of all font textures - both atlased and non-atlased Fonts/FontCache.h  
bFlushRequested volatile bool Whether or not we have a pending request to flush the cache when it is safe to do so Fonts/FontCache.h  
ColorFontAtlasIndices TArray< uint8 > Array of color font atlas indices for use with AllFontTextures (cast the element to FSlateFontAtlas) Fonts/FontCache.h  
CompositeFontCache TUniquePtr< FCompositeFontCache > High-level composite font cache (owned by this font cache) Fonts/FontCache.h  
EllipsisText FText Overflow text string to use to replace clipped characters Fonts/FontCache.h  
FCharacterList friend   Fonts/FontCache.h  
FontAtlasFactory TSharedRef< ISlateFontAtlasFactory > Factory for creating new font atlases Fonts/FontCache.h  
FontObjectsToFlush TArray< const UObject * > Array of UFont objects that the font cache has been requested to flush. Fonts/FontCache.h  
FontObjectsToFlushCS FCriticalSection Critical section preventing concurrent access to FontObjectsToFlush Fonts/FontCache.h  
FontRenderer TUniquePtr< FSlateFontRenderer > FreeType font renderer (owned by this font cache) Fonts/FontCache.h  
FontToCharacterListCache TMap< FSlateFontKey, TUniquePtr< FCharacterList >, FDefaultSetAllocator, FSlateFontKeyFuncs< TUniquePtr< FCharacterList > > > Mapping Font keys to cached data Fonts/FontCache.h  
FTCacheDirectory TUniquePtr< FFreeTypeCacheDirectory > FreeType low-level cache directory (owned by this font cache) Fonts/FontCache.h  
FTLibrary TUniquePtr< FFreeTypeLibrary > FreeType library instance (owned by this font cache) Fonts/FontCache.h  
GrayscaleFontAtlasIndices TArray< uint8 > Array of grayscale font atlas indices for use with AllFontTextures (cast the element to FSlateFontAtlas) Fonts/FontCache.h  
MsdfFontAtlasIndices TArray< uint8 > Array of multi-channel distance field font atlas indices for use with AllFontTextures (cast the element to FSlateFontAtlas) Fonts/FontCache.h  
NonAtlasedTextureIndices TArray< uint8 > Array of any non-atlased font texture indices for use with AllFontTextures Fonts/FontCache.h  
OnReleaseResourcesDelegate FOnReleaseFontResources Called after releasing the rendering resources in ReleaseResources Fonts/FontCache.h  
OwningThread ESlateTextureAtlasThreadId   Fonts/FontCache.h  
SdfGenerator TUniquePtr< FSlateSdfGenerator > Sdf Rasterizer for Freetype fonts Fonts/FontCache.h  
SdfGlyphToAtlasData TMap< FSdfGlyphEntryKey, TSharedRef< FSdfGlyphFontAtlasData > > Mapping signed distance field glyphs to their cached atlas data Fonts/FontCache.h  
SdfTaskToAtlasData TMap< FSdfGlyphTaskKey, TSharedRef< FSdfGlyphFontAtlasData > > Mapping unfinished signed distance field tasks to their cached atlas data Fonts/FontCache.h  
ShapedGlyphToAtlasData TMap< FShapedGlyphEntryKey, TSharedRef< FShapedGlyphFontAtlasData > > Mapping shaped glyphs to their cached atlas data Fonts/FontCache.h  
TextShaper TUniquePtr< FSlateTextShaper > HarfBuzz text shaper (owned by this font cache) Fonts/FontCache.h  

Functions

Public

Name Remarks Include Path Unreal Specifiers

bool CanLoadCodepoint ( const FFontData& InFontData,
const UTF32CHAR InCodepoint,
EFontFallback MaxFallbackLevel
) const

 Whether or not the specified character, within the specified font, can be loaded with the specified maximum font fallback level Fonts/FontCache.h  

bool ConditionalFlushCache()

 Flush the cache if needed Fonts/FontCache.h  

void FlushCompositeFont ( const FCompositeFont& InCompositeFont
)

 Flush the given composite font out of the cache Fonts/FontCache.h  

void FlushData()

 Clears just the cached font data, but leaves the atlases alone Fonts/FontCache.h  

void FlushObject ( const UObject*const InObject
)

 Flush the given object out of the cache Fonts/FontCache.h  

TArray< FString > GetAvailableFontSubFaces ( FFontFaceDataConstRef InMemory
) const

 Get the available sub-face data from the given font. Fonts/FontCache.h  

TArray< FString > GetAvailableFontSubFaces ( const FString& InFilename
) const

   Fonts/FontCache.h  

int16 GetBaseline ( const FSlateFontInfo& InFontInfo,
float FontScale
) const

 Returns the baseline for the specified font. Fonts/FontCache.h  

FCharacterList & GetCharacterList ( const FSlateFontInfo& InFontInfo,
float FontScale,
const FFontOutlineSettings& InOutlineSettings
)

 Gets information for how to draw all non-shaped characters in the specified string. Fonts/FontCache.h  

const FFontData & GetDefaultFontData ( const FSlateFontInfo& InFontInfo
) const

 Returns the font to use from the default typeface Fonts/FontCache.h  

const TSet< FName > & GetFontAttributes ( const FFontData& InFontData
) const

 Returns the font attributes for the specified font. Fonts/FontCache.h  

SIZE_T GetFontDataAssetResidentMemory ( const UObject* FontDataAsset
) const

 Gets the allocated font face data for a font data asset Fonts/FontCache.h  

const FFontData & GetFontDataForCodepoint ( const FSlateFontInfo& InFontInfo,
const UTF32CHAR InCodepoint,
float& OutScalingFactor
) const

 Returns the font to use from the typeface associated with the given codepoint Fonts/FontCache.h  

ISlateFontTexture * GetFontTexture ( uint32 Index
)

 Get the texture resource for a font atlas at a given index Fonts/FontCache.h  

int8 GetKerning ( const FFontData& InFontData,
const float InSize,
TCHAR First,
TCHAR Second,
float Scale
) const

 Calculates the kerning amount for a pair of characters Fonts/FontCache.h  

uint16 GetMaxCharacterHeight ( const FSlateFontInfo& InFontInfo,
float FontScale
) const

 Returns the height of the largest character in the font. Fonts/FontCache.h  

FShapedGlyphSequenceRef GetOverflowEllipsisText ( const FSlateFontInfo& InFontInfo,
const float InFontScale
)

 Gets the overflow glyph sequence for a given font. Fonts/FontCache.h  

FSdfGlyphFontAtlasData GetSdfGlyphFontAtlasData ( const FShapedGlyphEntry& InShapedGlyph,
const FFontOutlineSettings& InOutlineSettings
)

 Get the atlas information and the scaled metrics of a given shaped sdf glyph. Fonts/FontCache.h  

FShapedGlyphFontAtlasData GetShapedGlyphFontAtlasData ( const FShapedGlyphEntry& InShapedGlyph,
const FFontOutlineSettings& InOutlineSettings
)

 Get the atlas information for the given shaped glyph. This information will be cached if required Fonts/FontCache.h  

void GetStrikeMetrics ( const FSlateFontInfo& InFontInfo,
const float FontScale,
int16& OutStrikeLinePos,
int16& OutStrikeLineThickness
) const

 Get the strike metrics for the specified font. Fonts/FontCache.h  

void GetUnderlineMetrics ( const FSlateFontInfo& InFontInfo,
const float FontScale,
int16& OutUnderlinePos,
int16& OutUnderlineThickness
) const

 Get the underline metrics for the specified font. Fonts/FontCache.h  

bool HasKerning ( const FFontData& InFontData
) const

   Fonts/FontCache.h  

bool HasLoadedFontForCodepoint ( const FSlateFontInfo& InFontInfo,
const UTF32CHAR InCodepoint
) const

 Returns true if the font to use from the typeface associated with the given codepoint is already loaded Fonts/FontCache.h  

FOnReleaseFontResources & OnReleaseResources()

 Event called after releasing the rendering resources in ReleaseResources Fonts/FontCache.h  

void ReleaseResources()

 Releases rendering resources Fonts/FontCache.h  

FShapedGlyphSequenceRef ShapeBidirectionalText ( const FString& InText,
const FSlateFontInfo& InFontInfo,
const float InFontScale,
const TextBiDi::ETextDirection InBaseDirection,
const ETextShapingMethod InTextShapingMethod
) const

 Performs text shaping on the given string using the given font info. Fonts/FontCache.h  

FShapedGlyphSequenceRef ShapeBidirectionalText ( const TCHAR* InText,
const int32 InTextStart,
const int32 InTextLen,
const FSlateFontInfo& InFontInfo,
const float InFontScale,
const TextBiDi::ETextDirection InBaseDirection,
const ETextShapingMethod InTextShapingMethod
) const

   Fonts/FontCache.h  

FShapedGlyphSequenceRef ShapeOverflowEllipsisText ( const FSlateFontInfo& InFontInfo,
const float InFontScale
)

 Performs text shaping on the overflow glyph sequence for a given font. Fonts/FontCache.h  

FShapedGlyphSequenceRef ShapeUnidirectionalText ( const FString& InText,
const FSlateFontInfo& InFontInfo,
const float InFontScale,
const TextBiDi::ETextDirection InTextDirection,
const ETextShapingMethod InTextShapingMethod
) const

 Performs text shaping on the given range of the string using the given font info. Fonts/FontCache.h  

FShapedGlyphSequenceRef ShapeUnidirectionalText ( const TCHAR* InText,
const int32 InTextStart,
const int32 InTextLen,
const FSlateFontInfo& InFontInfo,
const float InFontScale,
const TextBiDi::ETextDirection InTextDirection,
const ETextShapingMethod InTextShapingMethod
) const

   Fonts/FontCache.h  

void UpdateCache()

 Updates the texture used for rendering Fonts/FontCache.h  

Overridden from ISlateAtlasProvider

Name Remarks Include Path Unreal Specifiers

virtual FSlateShaderResource * GetAtlasPageResource ( const int32 InIndex
) const

 Get the page resource for the given index (verify with GetNumAtlasPages) Fonts/FontCache.h  

virtual FAtlasSlotInfo GetAtlasSlotInfoAtPosition ( FIntPoint InPosition,
int32 AtlasIndex
) const

 Finds a currently occupied slot at a position specified in atlas coordinates where 0,0 is the top left and the size of the atlas is bottom right Fonts/FontCache.h  

virtual int32 GetNumAtlasPages()

 ISlateAtlasProvider Fonts/FontCache.h  

virtual bool IsAtlasPageResourceAlphaOnly ( const int32 InIndex
) const

 Does the page resources for the given index only contain alpha information? This affects how the atlas visualizer will sample them (verify with GetNumAtlasPages) Fonts/FontCache.h  

Overridden from FSlateFlushableAtlasCache

Name Remarks Include Path Unreal Specifiers

virtual void RequestFlushCache ( const FString& FlushReason
)

 Issues a request to clear all cached data from the cache Fonts/FontCache.h  

Operators

Name Remarks Include Path Unreal Specifiers

FSlateFontCache & operator= ( const FSlateFontCache&
)

   Fonts/FontCache.h  

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