| /***************************************************************************/ |
| /* */ |
| /* ftcache.h */ |
| /* */ |
| /* FreeType Cache subsystem (specification). */ |
| /* */ |
| /* Copyright 1996-2001, 2002, 2003, 2004, 2005 by */ |
| /* David Turner, Robert Wilhelm, and Werner Lemberg. */ |
| /* */ |
| /* This file is part of the FreeType project, and may only be used, */ |
| /* modified, and distributed under the terms of the FreeType project */ |
| /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ |
| /* this file you indicate that you have read the license and */ |
| /* understand and accept it fully. */ |
| /* */ |
| /***************************************************************************/ |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /********* *********/ |
| /********* WARNING, THIS IS BETA CODE. *********/ |
| /********* *********/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| |
| #ifndef __FTCACHE_H__ |
| #define __FTCACHE_H__ |
| |
| |
| #include <ft2build.h> |
| #include FT_GLYPH_H |
| |
| |
| FT_BEGIN_HEADER |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Section> */ |
| /* cache_subsystem */ |
| /* */ |
| /* <Title> */ |
| /* Cache Sub-System */ |
| /* */ |
| /* <Abstract> */ |
| /* How to cache face, size, and glyph data with FreeType 2. */ |
| /* */ |
| /* <Description> */ |
| /* This section describes the FreeType 2 cache sub-system which is */ |
| /* still in beta. */ |
| /* */ |
| /* <Order> */ |
| /* FTC_Manager */ |
| /* FTC_FaceID */ |
| /* FTC_Face_Requester */ |
| /* */ |
| /* FTC_Manager_New */ |
| /* FTC_Manager_Reset */ |
| /* FTC_Manager_Done */ |
| /* FTC_Manager_LookupFace */ |
| /* FTC_Manager_LookupSize */ |
| /* FTC_Manager_RemoveFaceID */ |
| /* */ |
| /* FTC_Node */ |
| /* FTC_Node_Unref */ |
| /* */ |
| /* FTC_Font */ |
| /* FTC_ImageCache */ |
| /* FTC_ImageCache_New */ |
| /* FTC_ImageCache_Lookup */ |
| /* */ |
| /* FTC_SBit */ |
| /* FTC_SBitCache */ |
| /* FTC_SBitCache_New */ |
| /* FTC_SBitCache_Lookup */ |
| /* */ |
| /* FTC_CMapCache */ |
| /* FTC_CMapCache_New */ |
| /* FTC_CMapCache_Lookup */ |
| /* */ |
| /*************************************************************************/ |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** BASIC TYPE DEFINITIONS *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Type> */ |
| /* FTC_FaceID */ |
| /* */ |
| /* <Description> */ |
| /* An opaque pointer type that is used to identity face objects. The */ |
| /* contents of such objects is application-dependent. */ |
| /* */ |
| typedef struct FTC_FaceIDRec_* FTC_FaceID; |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <FuncType> */ |
| /* FTC_Face_Requester */ |
| /* */ |
| /* <Description> */ |
| /* A callback function provided by client applications. It is used */ |
| /* to translate a given @FTC_FaceID into a new valid @FT_Face object. */ |
| /* */ |
| /* <Input> */ |
| /* face_id :: The face ID to resolve. */ |
| /* */ |
| /* library :: A handle to a FreeType library object. */ |
| /* */ |
| /* data :: Application-provided request data. */ |
| /* */ |
| /* <Output> */ |
| /* aface :: A new @FT_Face handle. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. */ |
| /* */ |
| /* <Note> */ |
| /* The face requester should not perform funny things on the returned */ |
| /* face object, like creating a new @FT_Size for it, or setting a */ |
| /* transformation through @FT_Set_Transform! */ |
| /* */ |
| typedef FT_Error |
| (*FTC_Face_Requester)( FTC_FaceID face_id, |
| FT_Library library, |
| FT_Pointer request_data, |
| FT_Face* aface ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Struct> */ |
| /* FTC_FontRec */ |
| /* */ |
| /* <Description> */ |
| /* A simple structure used to describe a given `font' to the cache */ |
| /* manager. Note that a `font' is the combination of a given face */ |
| /* with a given character size. */ |
| /* */ |
| /* <Fields> */ |
| /* face_id :: The ID of the face to use. */ |
| /* */ |
| /* pix_width :: The character width in integer pixels. */ |
| /* */ |
| /* pix_height :: The character height in integer pixels. */ |
| /* */ |
| typedef struct FTC_FontRec_ |
| { |
| FTC_FaceID face_id; |
| FT_UShort pix_width; |
| FT_UShort pix_height; |
| |
| } FTC_FontRec; |
| |
| |
| /* */ |
| |
| |
| #define FTC_FONT_COMPARE( f1, f2 ) \ |
| ( (f1)->face_id == (f2)->face_id && \ |
| (f1)->pix_width == (f2)->pix_width && \ |
| (f1)->pix_height == (f2)->pix_height ) |
| |
| #define FT_POINTER_TO_ULONG( p ) ((FT_ULong)(FT_Pointer)(p)) |
| |
| #define FTC_FACE_ID_HASH( i ) \ |
| ((FT_UInt32)(( FT_POINTER_TO_ULONG( i ) >> 3 ) ^ \ |
| ( FT_POINTER_TO_ULONG( i ) << 7 ) ) ) |
| |
| #define FTC_FONT_HASH( f ) \ |
| (FT_UInt32)( FTC_FACE_ID_HASH((f)->face_id) ^ \ |
| ((f)->pix_width << 8) ^ \ |
| ((f)->pix_height) ) |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Type> */ |
| /* FTC_Font */ |
| /* */ |
| /* <Description> */ |
| /* A simple handle to an @FTC_FontRec structure. */ |
| /* */ |
| typedef FTC_FontRec* FTC_Font; |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** CACHE MANAGER OBJECT *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Type> */ |
| /* FTC_Manager */ |
| /* */ |
| /* <Description> */ |
| /* This object is used to cache one or more @FT_Face objects, along */ |
| /* with corresponding @FT_Size objects. */ |
| /* */ |
| typedef struct FTC_ManagerRec_* FTC_Manager; |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Type> */ |
| /* FTC_Node */ |
| /* */ |
| /* <Description> */ |
| /* An opaque handle to a cache node object. Each cache node is */ |
| /* reference-counted. A node with a count of 0 might be flushed */ |
| /* out of a full cache whenever a lookup request is performed. */ |
| /* */ |
| /* If you lookup nodes, you have the ability to "acquire" them, i.e., */ |
| /* to increment their reference count. This will prevent the node */ |
| /* from being flushed out of the cache until you explicitly "release" */ |
| /* it (see @FTC_Node_Unref). */ |
| /* */ |
| /* See also @FTC_SBitCache_Lookup and @FTC_ImageCache_Lookup. */ |
| /* */ |
| typedef struct FTC_NodeRec_* FTC_Node; |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FTC_Manager_New */ |
| /* */ |
| /* <Description> */ |
| /* Creates a new cache manager. */ |
| /* */ |
| /* <Input> */ |
| /* library :: The parent FreeType library handle to use. */ |
| /* */ |
| /* max_bytes :: Maximum number of bytes to use for cached data */ |
| /* nodes. Use 0 for defaults. Note that this value */ |
| /* does not account for managed FT_Face and FT_Size */ |
| /* objects. */ |
| /* */ |
| /* requester :: An application-provided callback used to translate */ |
| /* face IDs into real @FT_Face objects. */ |
| /* */ |
| /* req_data :: A generic pointer that is passed to the requester */ |
| /* each time it is called (see @FTC_Face_Requester). */ |
| /* */ |
| /* <Output> */ |
| /* amanager :: A handle to a new manager object. 0 in case of */ |
| /* failure. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. */ |
| /* */ |
| /* <Note> */ |
| /* When you perform a lookup, out-of-memory errors are detected */ |
| /* _within_ the lookup and force incremental flushes of the cache */ |
| /* until enough memory is released for the lookup to succeed. */ |
| /* */ |
| /* If a lookup fails with FT_Err_Out_Of_Memory the cache has already */ |
| /* been completely flushed, and still no memory is available for the */ |
| /* operation. */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FTC_Manager_New( FT_Library library, |
| FT_UInt max_faces, |
| FT_UInt max_sizes, |
| FT_ULong max_bytes, |
| FTC_Face_Requester requester, |
| FT_Pointer req_data, |
| FTC_Manager *amanager ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FTC_Manager_Reset */ |
| /* */ |
| /* <Description> */ |
| /* Empties a given cache manager. This simply gets rid of all the */ |
| /* currently cached @FT_Face and @FT_Size objects within the manager. */ |
| /* */ |
| /* <InOut> */ |
| /* manager :: A handle to the manager. */ |
| /* */ |
| FT_EXPORT( void ) |
| FTC_Manager_Reset( FTC_Manager manager ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FTC_Manager_Done */ |
| /* */ |
| /* <Description> */ |
| /* Destroys a given manager after emptying it. */ |
| /* */ |
| /* <Input> */ |
| /* manager :: A handle to the target cache manager object. */ |
| /* */ |
| FT_EXPORT( void ) |
| FTC_Manager_Done( FTC_Manager manager ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FTC_Manager_LookupFace */ |
| /* */ |
| /* <Description> */ |
| /* Retrieves the @FT_Face object that corresponds to a given face ID */ |
| /* through a cache manager. */ |
| /* */ |
| /* <Input> */ |
| /* manager :: A handle to the cache manager. */ |
| /* */ |
| /* face_id :: The ID of the face object. */ |
| /* */ |
| /* <Output> */ |
| /* aface :: A handle to the face object. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. */ |
| /* */ |
| /* <Note> */ |
| /* The returned @FT_Face object is always owned by the manager. You */ |
| /* should never try to discard it yourself. */ |
| /* */ |
| /* The @FT_Face object doesn't necessarily have a current size object */ |
| /* (i.e., face->size can be 0). If you need a specific `font size', */ |
| /* use @FTC_Manager_LookupSize instead. */ |
| /* */ |
| /* Never change the face's transformation matrix (i.e., never call */ |
| /* the @FT_Set_Transform function) on a returned face! If you need */ |
| /* to transform glyphs, do it yourself after glyph loading. */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FTC_Manager_LookupFace( FTC_Manager manager, |
| FTC_FaceID face_id, |
| FT_Face *aface ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Struct> */ |
| /* FTC_ScalerRec */ |
| /* */ |
| /* <Description> */ |
| /* A structure used to describe a given character size in either */ |
| /* pixels or points to the cache manager. See */ |
| /* @FTC_Manager_LookupSize. */ |
| /* */ |
| /* <Fields> */ |
| /* face_id :: The source face ID. */ |
| /* */ |
| /* width :: The character width. */ |
| /* */ |
| /* height :: The character height. */ |
| /* */ |
| /* pixel :: A Boolean. If TRUE, the `width' and `height' fields */ |
| /* are interpreted as integer pixel character sizes. */ |
| /* Otherwise, they are expressed as 1/64th of points. */ |
| /* */ |
| /* x_res :: Only used when `pixel' is FALSE to indicate the */ |
| /* horizontal resolution in dpi. */ |
| /* */ |
| /* y_res :: Only used when `pixel' is FALSE to indicate the */ |
| /* vertical resolution in dpi. */ |
| /* */ |
| /* <Note> */ |
| /* This type is mainly used to retrieve @FT_Size objects through the */ |
| /* cache manager. */ |
| /* */ |
| typedef struct FTC_ScalerRec_ |
| { |
| FTC_FaceID face_id; |
| FT_UInt width; |
| FT_UInt height; |
| FT_Int pixel; |
| FT_UInt x_res; |
| FT_UInt y_res; |
| |
| } FTC_ScalerRec, *FTC_Scaler; |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FTC_Manager_LookupSize */ |
| /* */ |
| /* <Description> */ |
| /* Retrieve the @FT_Size object that corresponds to a given */ |
| /* @FTC_Scaler through a cache manager. */ |
| /* */ |
| /* <Input> */ |
| /* manager :: A handle to the cache manager. */ |
| /* */ |
| /* scaler :: A scaler handle. */ |
| /* */ |
| /* <Output> */ |
| /* asize :: A handle to the size object. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. */ |
| /* */ |
| /* <Note> */ |
| /* The returned @FT_Size object is always owned by the manager. You */ |
| /* should never try to discard it by yourself. */ |
| /* */ |
| /* You can access the parent @FT_Face object simply as `size->face' */ |
| /* if you need it. Note that this object is also owned by the */ |
| /* manager. */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FTC_Manager_LookupSize( FTC_Manager manager, |
| FTC_Scaler scaler, |
| FT_Size *asize ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FTC_Node_Unref */ |
| /* */ |
| /* <Description> */ |
| /* Decrement a cache node's internal reference count. When the count */ |
| /* reaches 0, it is not destroyed but becomes eligible for subsequent */ |
| /* cache flushes. */ |
| /* */ |
| /* <Input> */ |
| /* node :: The cache node handle. */ |
| /* */ |
| /* manager :: The cache manager handle. */ |
| /* */ |
| FT_EXPORT( void ) |
| FTC_Node_Unref( FTC_Node node, |
| FTC_Manager manager ); |
| |
| |
| /* remove all nodes belonging to a given face_id */ |
| FT_EXPORT( void ) |
| FTC_Manager_RemoveFaceID( FTC_Manager manager, |
| FTC_FaceID face_id ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Section> */ |
| /* cache_subsystem */ |
| /* */ |
| /*************************************************************************/ |
| |
| /************************************************************************* |
| * |
| * @type: |
| * FTC_CMapCache |
| * |
| * @description: |
| * An opaque handle used to manager a charmap cache. This cache is to |
| * hold character codes -> glyph indices mappings. |
| * |
| */ |
| typedef struct FTC_CMapCacheRec_* FTC_CMapCache; |
| |
| |
| /************************************************************************* |
| * |
| * @function: |
| * FTC_CMapCache_New |
| * |
| * @description: |
| * Create a new charmap cache. |
| * |
| * @input: |
| * manager :: |
| * A handle to the cache manager. |
| * |
| * @output: |
| * acache :: |
| * A new cache handle. NULL in case of error. |
| * |
| * @return: |
| * FreeType error code. 0 means success. |
| * |
| * @note: |
| * Like all other caches, this one will be destroyed with the cache |
| * manager. |
| * |
| */ |
| FT_EXPORT( FT_Error ) |
| FTC_CMapCache_New( FTC_Manager manager, |
| FTC_CMapCache *acache ); |
| |
| |
| /************************************************************************ |
| * |
| * @function: |
| * FTC_CMapCache_Lookup |
| * |
| * @description: |
| * Translate a character code into a glyph index, using the charmap |
| * cache. |
| * |
| * @input: |
| * cache :: |
| * A charmap cache handle. |
| * |
| * face_id :: |
| * The source face ID. |
| * |
| * cmap_index :: |
| * The index of the charmap in the source face. |
| * |
| * char_code :: |
| * The character code (in the corresponding charmap). |
| * |
| * @return: |
| * Glyph index. 0 means `no glyph'. |
| * |
| */ |
| FT_EXPORT( FT_UInt ) |
| FTC_CMapCache_Lookup( FTC_CMapCache cache, |
| FTC_FaceID face_id, |
| FT_Int cmap_index, |
| FT_UInt32 char_code ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Section> */ |
| /* cache_subsystem */ |
| /* */ |
| /*************************************************************************/ |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** IMAGE CACHE OBJECT *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| typedef struct FTC_ImageTypeRec_ |
| { |
| FTC_FaceID face_id; |
| FT_Int width; |
| FT_Int height; |
| FT_Int32 flags; |
| |
| } FTC_ImageTypeRec; |
| |
| typedef struct FTC_ImageTypeRec_* FTC_ImageType; |
| |
| /* */ |
| |
| #define FTC_IMAGE_TYPE_COMPARE( d1, d2 ) \ |
| ( FTC_FONT_COMPARE( &(d1)->font, &(d2)->font ) && \ |
| (d1)->flags == (d2)->flags ) |
| |
| #define FTC_IMAGE_TYPE_HASH( d ) \ |
| (FT_UFast)( FTC_FONT_HASH( &(d)->font ) ^ \ |
| ( (d)->flags << 4 ) ) |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Type> */ |
| /* FTC_ImageCache */ |
| /* */ |
| /* <Description> */ |
| /* A handle to an glyph image cache object. They are designed to */ |
| /* hold many distinct glyph images while not exceeding a certain */ |
| /* memory threshold. */ |
| /* */ |
| typedef struct FTC_ImageCacheRec_* FTC_ImageCache; |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FTC_ImageCache_New */ |
| /* */ |
| /* <Description> */ |
| /* Creates a new glyph image cache. */ |
| /* */ |
| /* <Input> */ |
| /* manager :: The parent manager for the image cache. */ |
| /* */ |
| /* <Output> */ |
| /* acache :: A handle to the new glyph image cache object. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FTC_ImageCache_New( FTC_Manager manager, |
| FTC_ImageCache *acache ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FTC_ImageCache_Lookup */ |
| /* */ |
| /* <Description> */ |
| /* Retrieves a given glyph image from a glyph image cache. */ |
| /* */ |
| /* <Input> */ |
| /* cache :: A handle to the source glyph image cache. */ |
| /* */ |
| /* type :: A pointer to a glyph image type descriptor. */ |
| /* */ |
| /* gindex :: The glyph index to retrieve. */ |
| /* */ |
| /* <Output> */ |
| /* aglyph :: The corresponding @FT_Glyph object. 0 in case of */ |
| /* failure. */ |
| /* */ |
| /* anode :: Used to return the address of of the corresponding cache */ |
| /* node after incrementing its reference count (see note */ |
| /* below). */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. */ |
| /* */ |
| /* <Note> */ |
| /* The returned glyph is owned and managed by the glyph image cache. */ |
| /* Never try to transform or discard it manually! You can however */ |
| /* create a copy with @FT_Glyph_Copy and modify the new one. */ |
| /* */ |
| /* If `anode' is _not_ NULL, it receives the address of the cache */ |
| /* node containing the glyph image, after increasing its reference */ |
| /* count. This ensures that the node (as well as the FT_Glyph) will */ |
| /* always be kept in the cache until you call @FTC_Node_Unref to */ |
| /* `release' it. */ |
| /* */ |
| /* If `anode' is NULL, the cache node is left unchanged, which means */ |
| /* that the FT_Glyph could be flushed out of the cache on the next */ |
| /* call to one of the caching sub-system APIs. Don't assume that it */ |
| /* is persistent! */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FTC_ImageCache_Lookup( FTC_ImageCache cache, |
| FTC_ImageType type, |
| FT_UInt gindex, |
| FT_Glyph *aglyph, |
| FTC_Node *anode ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Type> */ |
| /* FTC_SBit */ |
| /* */ |
| /* <Description> */ |
| /* A handle to a small bitmap descriptor. See the @FTC_SBitRec */ |
| /* structure for details. */ |
| /* */ |
| typedef struct FTC_SBitRec_* FTC_SBit; |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Struct> */ |
| /* FTC_SBitRec */ |
| /* */ |
| /* <Description> */ |
| /* A very compact structure used to describe a small glyph bitmap. */ |
| /* */ |
| /* <Fields> */ |
| /* width :: The bitmap width in pixels. */ |
| /* */ |
| /* height :: The bitmap height in pixels. */ |
| /* */ |
| /* left :: The horizontal distance from the pen position to the */ |
| /* left bitmap border (a.k.a. `left side bearing', or */ |
| /* `lsb'). */ |
| /* */ |
| /* top :: The vertical distance from the pen position (on the */ |
| /* baseline) to the upper bitmap border (a.k.a. `top */ |
| /* side bearing'). The distance is positive for upwards */ |
| /* Y coordinates. */ |
| /* */ |
| /* format :: The format of the glyph bitmap (monochrome or gray). */ |
| /* */ |
| /* max_grays :: Maximum gray level value (in the range 1 to 255). */ |
| /* */ |
| /* pitch :: The number of bytes per bitmap line. May be positive */ |
| /* or negative. */ |
| /* */ |
| /* xadvance :: The horizontal advance width in pixels. */ |
| /* */ |
| /* yadvance :: The vertical advance height in pixels. */ |
| /* */ |
| /* buffer :: A pointer to the bitmap pixels. */ |
| /* */ |
| typedef struct FTC_SBitRec_ |
| { |
| FT_Byte width; |
| FT_Byte height; |
| FT_Char left; |
| FT_Char top; |
| |
| FT_Byte format; |
| FT_Byte max_grays; |
| FT_Short pitch; |
| FT_Char xadvance; |
| FT_Char yadvance; |
| |
| FT_Byte* buffer; |
| |
| } FTC_SBitRec; |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Type> */ |
| /* FTC_SBitCache */ |
| /* */ |
| /* <Description> */ |
| /* A handle to a small bitmap cache. These are special cache objects */ |
| /* used to store small glyph bitmaps (and anti-aliased pixmaps) in a */ |
| /* much more efficient way than the traditional glyph image cache */ |
| /* implemented by @FTC_ImageCache. */ |
| /* */ |
| typedef struct FTC_SBitCacheRec_* FTC_SBitCache; |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FTC_SBitCache_New */ |
| /* */ |
| /* <Description> */ |
| /* Creates a new cache to store small glyph bitmaps. */ |
| /* */ |
| /* <Input> */ |
| /* manager :: A handle to the source cache manager. */ |
| /* */ |
| /* <Output> */ |
| /* acache :: A handle to the new sbit cache. NULL in case of error. */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FTC_SBitCache_New( FTC_Manager manager, |
| FTC_SBitCache *acache ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FTC_SBitCache_Lookup */ |
| /* */ |
| /* <Description> */ |
| /* Looks up a given small glyph bitmap in a given sbit cache and */ |
| /* `lock' it to prevent its flushing from the cache until needed. */ |
| /* */ |
| /* <Input> */ |
| /* cache :: A handle to the source sbit cache. */ |
| /* */ |
| /* type :: A pointer to the glyph image type descriptor. */ |
| /* */ |
| /* gindex :: The glyph index. */ |
| /* */ |
| /* <Output> */ |
| /* sbit :: A handle to a small bitmap descriptor. */ |
| /* */ |
| /* anode :: Used to return the address of of the corresponding cache */ |
| /* node after incrementing its reference count (see note */ |
| /* below). */ |
| /* */ |
| /* <Return> */ |
| /* FreeType error code. 0 means success. */ |
| /* */ |
| /* <Note> */ |
| /* The small bitmap descriptor and its bit buffer are owned by the */ |
| /* cache and should never be freed by the application. They might */ |
| /* as well disappear from memory on the next cache lookup, so don't */ |
| /* treat them as persistent data. */ |
| /* */ |
| /* The descriptor's `buffer' field is set to 0 to indicate a missing */ |
| /* glyph bitmap. */ |
| /* */ |
| /* If `anode' is _not_ NULL, it receives the address of the cache */ |
| /* node containing the bitmap, after increasing its reference count. */ |
| /* This ensures that the node (as well as the image) will always be */ |
| /* kept in the cache until you call @FTC_Node_Unref to `release' it. */ |
| /* */ |
| /* If `anode' is NULL, the cache node is left unchanged, which means */ |
| /* that the bitmap could be flushed out of the cache on the next */ |
| /* call to one of the caching sub-system APIs. Don't assume that it */ |
| /* is persistent! */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FTC_SBitCache_Lookup( FTC_SBitCache cache, |
| FTC_ImageType type, |
| FT_UInt gindex, |
| FTC_SBit *sbit, |
| FTC_Node *anode ); |
| |
| |
| /* */ |
| |
| FT_END_HEADER |
| |
| #endif /* __FTCACHE_H__ */ |
| |
| |
| /* END */ |