typedef struct FT_LibraryRec_  *FT_Library;

A handle to a FreeType library instance. Each `library' is completely independent from the others; it is the `root' of a set of objects like fonts, faces, sizes, etc.

It also embeds a memory manager (see FT_Memory ), as well as a scan-line converter object (see FT_Raster ).

Library objects are normally created by FT_Init_FreeType , and destroyed with FT_Done_FreeType

  typedef struct FT_FaceRec_*  FT_Face;

A handle to a given typographic face object. A face object models a given typeface, in a given style.

Each face object also owns a single FT_GlyphSlot object, as well as one or more FT_Size objects.

use FT_New_Face or FT_Open_Face to create a new face object from a given filepathname or a custom input stream.

use FT_Done_Face to destroy it (along with its slot and sizes)

  typedef struct FT_SizeRec_*  FT_Size;

A handle to a given size object. Such an object models the data that depends on the current _resolution_ and _character_ _size_ in a given FT_Face .

Each face object owns one or more sizes. There is however a single _active_ size for the face at any time that will be used by functions like FT_Load_Glyph , FT_Get_Kerning , etc...

you can use the FT_Activate_Size API to change the current active size of any given face

  typedef struct FT_GlyphSlotRec_*  FT_GlyphSlot;

A handle to a given `glyph slot'. A slot is a container where it is possible to load any one of the glyphs contained in its parent face.

In other words, each time you call FT_Load_Glyph or FT_Load_Char , the slot's content is erased by the new glyph data, i.e. the glyph's metrics, its image (bitmap or outline), and other control information

  typedef struct FT_CharMapRec_*  FT_CharMap;

A handle to a given character map. A charmap is used to translate character codes in a given encoding into glyph indexes for its parent's face. Some font formats may provide several charmaps per font.

Each face object owns zero or more charmaps, but only one of them can be "active" and used by FT_Get_Char_Index or FT_Load_Char

The list of available charmaps in a face is available through the "face->num_charmaps" and "face->charmaps" fields of FT_FaceRec

the currently active charmap is available as "face->charmap". You should call FT_Set_Charmap to change it

when a new face is created (either through FT_New_Face or FT_Open_Face ), the library looks for a Unicode charmap within the list and automatically activates it

  typedef enum  FT_Encoding_
  {
    FT_ENC_TAG( ft_encoding_none, 0, 0, 0, 0 ),

    FT_ENC_TAG( ft_encoding_symbol,  's', 'y', 'm', 'b' ),
    FT_ENC_TAG( ft_encoding_unicode, 'u', 'n', 'i', 'c' ),
    FT_ENC_TAG( ft_encoding_latin_1, 'l', 'a', 't', '1' ),
    FT_ENC_TAG( ft_encoding_latin_2, 'l', 'a', 't', '2' ),
    FT_ENC_TAG( ft_encoding_sjis,    's', 'j', 'i', 's' ),
    FT_ENC_TAG( ft_encoding_gb2312,  'g', 'b', ' ', ' ' ),
    FT_ENC_TAG( ft_encoding_big5,    'b', 'i', 'g', '5' ),
    FT_ENC_TAG( ft_encoding_wansung, 'w', 'a', 'n', 's' ),
    FT_ENC_TAG( ft_encoding_johab,   'j', 'o', 'h', 'a' ),

    FT_ENC_TAG( ft_encoding_adobe_standard, 'A', 'D', 'O', 'B' ),
    FT_ENC_TAG( ft_encoding_adobe_expert,   'A', 'D', 'B', 'E' ),
    FT_ENC_TAG( ft_encoding_adobe_custom,   'A', 'D', 'B', 'C' ),

    FT_ENC_TAG( ft_encoding_apple_roman, 'a', 'r', 'm', 'n' )

  } FT_Encoding;

An enumeration used to specify encodings supported by charmaps. Used in the FT_Select_Charmap() API function.

Because of 32-bit charcodes defined in Unicode (i.e., surrogates), all character codes must be expressed as FT_Longs.

Other encodings might be defined in the future.

  typedef struct  FT_FaceRec_
  {
    FT_Long           num_faces;
    FT_Long           face_index;

    FT_Long           face_flags;
    FT_Long           style_flags;

    FT_Long           num_glyphs;

    FT_String*        family_name;
    FT_String*        style_name;

    FT_Int            num_fixed_sizes;
    FT_Bitmap_Size*   available_sizes;

    FT_Int            num_charmaps;
    FT_CharMap*       charmaps;

    FT_Generic        generic;

    /*# the following are only relevant to scalable outlines */
    FT_BBox           bbox;

    FT_UShort         units_per_EM;
    FT_Short          ascender;
    FT_Short          descender;
    FT_Short          height;

    FT_Short          max_advance_width;
    FT_Short          max_advance_height;

    FT_Short          underline_position;
    FT_Short          underline_thickness;

    FT_GlyphSlot      glyph;
    FT_Size           size;
    FT_CharMap        charmap;

    /*@private begin */

    FT_Driver         driver;
    FT_Memory         memory;
    FT_Stream         stream;

    FT_ListRec        sizes_list;

    FT_Generic        autohint;
    void*             extensions;

    FT_Face_Internal  internal;

    /*@private end */

  } FT_FaceRec;

FreeType root face class structure. A face object models the resolution and point-size independent data found in a font file.

#define FT_FACE_FLAG_SCALABLE  1

A bit-field constant, used to indicate that a given face provides vectorial outlines (i.e., TrueType or Type1). This doesn't prevent embedding of bitmap strikes though, i.e., a given face can have both this bit set, and a `num_fixed_sizes' property > 0.

#define FT_FACE_FLAG_FIXED_SIZES  2

A bit-field constant, used to indicate that a given face contains `fixed sizes', i.e., bitmap strikes for some given pixel sizes. See the `num_fixed_sizes' and `available_sizes' face properties for more information.

#define FT_FACE_FLAG_FIXED_WIDTH  4

A bit-field constant, used to indicate that a given face contains fixed-width characters (like Courier, Lucida, MonoType, etc.).

#define FT_FACE_FLAG_HORIZONTAL  0x10

A bit-field constant, used to indicate that a given face contains horizontal glyph metrics. This should be set for all common formats, but who knows.

#define FT_FACE_FLAG_VERTICAL  0x20

A bit-field constant, used to indicate that a given face contains vertical glyph metrics. If not set, the glyph loader will synthetize vertical metrics itself to help display vertical text correctly.

#define FT_FACE_FLAG_SFNT  8

A bit-field constant, used to indicate that a given face uses the `sfnt' storage fomat. For now, this means TrueType or OpenType.

#define FT_FACE_FLAG_KERNING  0x40

A bit-field constant, used to indicate that a given face contains kerning information. When set, this information can be retrieved through the function FT_Get_Kerning (). Note that when unset, this function will always return the kerning vector (0,0).

#define FT_FACE_FLAG_MULTIPLE_MASTERS  0x100

A bit-field constant, used to indicate that the font contains multiple masters and is capable of interpolating between them. See the multiple-masters specific API for more details

#define FT_FACE_FLAG_GLYPH_NAMES  0x200

A bit-field constant, used to indicate that the font contains glyph names that can be retrieved through FT_Get_Glyph_Name ().

#define FT_FACE_FLAG_EXTERNAL_STREAM  0x4000

This bit field is used internally by FreeType to indicate that a face's stream was provided by the client application and should not be destroyed by FT_Done_Face ().

#define FT_FACE_FLAG_FAST_GLYPHS  0x80

A bit-field constant, used to indicate that the glyphs in a given font can be retrieved very quickly, and that a glyph cache is thus not necessary for any of its child size objects.

This flag should really be set for fixed-size formats like FNT, where each glyph bitmap is available directly in binary form without any kind of compression.

This bit flag is deprecated, because even if the bitmaps are available directly in the font file, the glyph sub-system is very likely to be faster anyway...

#define FT_STYLE_FLAG_BOLD  2

A bit-field constant, used to indicate that a given face is emboldened.

#define FT_STYLE_FLAG_ITALIC  1

A bit-field constant, used to indicate that a given face is italicized.

  typedef struct  FT_SizeRec_
  {
    FT_Face           face;      /* parent face object              */
    FT_Generic        generic;   /* generic pointer for client uses */
    FT_Size_Metrics   metrics;   /* size metrics                    */
    FT_Size_Internal  internal;

  } FT_SizeRec;

FreeType root size class structure. A size object models the resolution and pointsize dependent data of a given face.

  typedef struct  FT_Size_Metrics_
  {
    FT_UShort  x_ppem;      /* horizontal pixels per EM               */
    FT_UShort  y_ppem;      /* vertical pixels per EM                 */

    FT_Fixed   x_scale;     /* two scales used to convert font units  */
    FT_Fixed   y_scale;     /* to 26.6 frac. pixel coordinates..      */

    FT_Pos     ascender;    /* ascender in 26.6 frac. pixels          */
    FT_Pos     descender;   /* descender in 26.6 frac. pixels         */
    FT_Pos     height;      /* text height in 26.6 frac. pixels       */
    FT_Pos     max_advance; /* max horizontal advance, in 26.6 pixels */

  } FT_Size_Metrics;

The size metrics structure returned scaled important distances for a given size object.

The values of `ascender', `descender', and `height' are only the scaled versions of `face->ascender', `face->descender', and `face->height'.

Unfortunately, due to glyph hinting, these values might not be exact for certain fonts, they thus must be treated as unreliable with an error margin of at least one pixel!

Indeed, the only way to get the exact pixel ascender and descender is to render _all_ glyphs. As this would be a definite performance hit, it is up to client applications to perform such computations.

  typedef struct  FT_GlyphSlotRec_
  {
    FT_Library        library;
    FT_Face           face;
    FT_GlyphSlot      next;
    FT_UInt           flags;
    FT_Generic        generic;

    FT_Glyph_Metrics  metrics;
    FT_Fixed          linearHoriAdvance;
    FT_Fixed          linearVertAdvance;
    FT_Vector         advance;

    FT_Glyph_Format   format;

    FT_Bitmap         bitmap;
    FT_Int            bitmap_left;
    FT_Int            bitmap_top;

    FT_Outline        outline;

    FT_UInt           num_subglyphs;
    FT_SubGlyph       subglyphs;

    void*             control_data;
    long              control_len;

    void*             other;

    FT_Slot_Internal  internal;

  } FT_GlyphSlotRec;

FreeType root glyph slot class structure. A glyph slot is a container where individual glyphs can be loaded, be they vectorial or bitmap/graymaps.

If FT_Load_Glyph () is called with default flags (see FT_LOAD_DEFAULT ) the glyph image is loaded in the glyph slot in its native format (e.g. a vectorial outline for TrueType and Type 1 formats).

This image can later be converted into a bitmap by calling FT_Render_Glyph(). This function finds the current renderer for the native image's format then invokes it.

The renderer is in charge of transforming the native image through the slot's face transformation fields, then convert it into a bitmap that is returned in `slot->bitmap'.

Note that `slot->bitmap_left' and `slot->bitmap_top' are also used to specify the position of the bitmap relative to the current pen position (e.g. coordinates [0,0] on the baseline). Of course, `slot->format' is also changed to `ft_glyph_format_bitmap' .

  typedef struct  FT_Glyph_Metrics_
  {
    FT_Pos  width;         /* glyph width  */
    FT_Pos  height;        /* glyph height */

    FT_Pos  horiBearingX;  /* left side bearing in horizontal layouts */
    FT_Pos  horiBearingY;  /* top side bearing in horizontal layouts  */
    FT_Pos  horiAdvance;   /* advance width for horizontal layout     */

    FT_Pos  vertBearingX;  /* left side bearing in vertical layouts */
    FT_Pos  vertBearingY;  /* top side bearing in vertical layouts  */
    FT_Pos  vertAdvance;   /* advance height for vertical layout    */

  } FT_Glyph_Metrics;

A structure used to model the metrics of a single glyph. Note that values are expressed in 26.6 fractional pixel format or in font units, depending on context.

  typedef struct FT_SubGlyphRec_*  FT_SubGlyph;

The subglyph structure is an internal object used to describe subglyphs (for example, in the case of composites).

The subglyph implementation is not part of the high-level API, hence the forward structure declaration.

  typedef struct  FT_Bitmap_Size_
  {
    FT_Short  height;
    FT_Short  width;

  } FT_Bitmap_Size;

An extremely simple structure used to model the size of a bitmap strike (i.e., a bitmap instance of the font for a given resolution) in a fixed-size font face. This is used for the `available_sizes' field of the FT_Face_Properties structure.

  FT_EXPORT( FT_Error )
  FT_Init_FreeType( FT_Library  *alibrary );

Initializes a new FreeType library object. The set of modules that are registered by this function is determined at build time.

FreeType error code. 0 means success.

  FT_EXPORT( FT_Error )
  FT_Done_FreeType( FT_Library  library );

Destroys a given FreeType library object and all of its childs, including resources, drivers, faces, sizes, etc.

FreeType error code. 0 means success.

  FT_EXPORT( void )
  FT_Library_Version( FT_Library   library,
                      FT_Int      *amajor,
                      FT_Int      *aminor,
                      FT_Int      *apatch );

Return the version of the FreeType library being used. This is useful when dynamically linking to the library, since one cannot use the macros FT_FREETYPE_MAJOR, FT_FREETYPE_MINOR, and FT_FREETYPE_PATCH.

The reason why this function takes a 'library' argument is because certain programs implement library initialization in a custom way that doesn't use `FT_Init_FreeType'.

In such cases, the library version might not be available before the library object has been created.

  FT_EXPORT( FT_Error )
  FT_New_Face( FT_Library   library,
               const char*  filepathname,
               FT_Long      face_index,
               FT_Face     *aface );

Creates a new face object from a given resource and typeface index using a pathname to the font file.

FreeType error code. 0 means success.

Unlike FreeType 1.x, this function automatically creates a glyph slot for the face object which can be accessed directly through `face->glyph'.

FT_New_Face() can be used to determine and/or check the font format of a given font resource. If the `face_index' field is negative, the function will _not_ return any face handle in `aface'. Its return value should be 0 if the font format is recognized, or non-zero otherwise.

Each new face object created with this function also owns a default FT_Size object, accessible as `face->size'

  FT_EXPORT( FT_Error )
  FT_Done_Face( FT_Face  face );

Discards a given face object, as well as all of its child slots and sizes.

FreeType error code. 0 means success.

  FT_EXPORT( FT_Error )
  FT_New_Memory_Face( FT_Library      library,
                      const FT_Byte*  file_base,
                      FT_Long         file_size,
                      FT_Long         face_index,
                      FT_Face        *aface );

Creates a new face object from a given resource and typeface index using a font file already loaded into memory.

FreeType error code. 0 means success.

The font data bytes are used _directly_ by the FT_Face object. This means that they are not copied, and that the client is responsible for releasing/destroying them _after_ the corresponding call to FT_Done_Face .

Unlike FreeType 1.x, this function automatically creates a glyph slot for the face object which can be accessed directly through `face->glyph'.

FT_New_Memory_Face() can be used to determine and/or check the font format of a given font resource. If the `face_index' field is negative, the function will _not_ return any face handle in `aface'. Its return value should be 0 if the font format is recognized, or non-zero otherwise.

  FT_EXPORT( FT_Error )
  FT_Open_Face( FT_Library     library,
                FT_Open_Args*  args,
                FT_Long        face_index,
                FT_Face       *aface );

Opens a face object from a given resource and typeface index using an `FT_Open_Args' structure. If the face object doesn't exist, it will be created.

FreeType error code. 0 means success.

Unlike FreeType 1.x, this function automatically creates a glyph slot for the face object which can be accessed directly through `face->glyph'.

FT_Open_Face() can be used to determine and/or check the font format of a given font resource. If the `face_index' field is negative, the function will _not_ return any face handle in `*face'. Its return value should be 0 if the font format is recognized, or non-zero otherwise.

  typedef struct  FT_Open_Args_
  {
    FT_Open_Flags   flags;
    const FT_Byte*  memory_base;
    FT_Long         memory_size;
    FT_String*      pathname;
    FT_Stream       stream;
    FT_Module       driver;
    FT_Int          num_params;
    FT_Parameter*   params;

  } FT_Open_Args;

A structure used to indicate how to open a new font file/stream. A pointer to such a structure can be used as a parameter for the functions FT_Open_Face () & FT_Attach_Stream ().

The stream type is determined by the contents of `flags' which are tested in the following order by FT_Open_Face :

If the `ft_open_memory' bit is set, assume that this is a memory file of `memory_size' bytes,located at `memory_address'.

Otherwise, if the `ft_open_stream' bit is set, assume that a custom input stream `stream' is used.

Otherwise, if the `ft_open_pathname' bit is set, assume that this is a normal file and use `pathname' to open it.

If the `ft_open_driver' bit is set, FT_Open_Face () will only try to open the file with the driver whose handler is in `driver'.

If the `ft_open_params' bit is set, the parameters given by `num_params' and `params' will be used. They are ignored otherwise.

  typedef enum
  {
    ft_open_memory   = 1,
    ft_open_stream   = 2,
    ft_open_pathname = 4,
    ft_open_driver   = 8,
    ft_open_params   = 16

  } FT_Open_Flags;

An enumeration used to list the bit flags used within the `flags' field of the FT_Open_Args structure.

The `ft_open_memory', `ft_open_stream', and `ft_open_pathname' flags are mutually exclusive.

  typedef struct  FT_Parameter_
  {
    FT_ULong    tag;
    FT_Pointer  data;

  } FT_Parameter;

A simple structure used to pass more or less generic parameters to FT_Open_Face().

The id and function of parameters are driver-specific.

  FT_EXPORT( FT_Error )
  FT_Attach_File( FT_Face      face,
                  const char*  filepathname );

`Attaches' a given font file to an existing face. This is usually to read additional information for a single face object. For example, it is used to read the AFM files that come with Type 1 fonts in order to add kerning data and other metrics.

FreeType error code. 0 means success.

If your font file is in memory, or if you want to provide your own input stream object, use FT_Attach_Stream().

The meaning of the `attach' action (i.e., what really happens when the new file is read) is not fixed by FreeType itself. It really depends on the font format (and thus the font driver).

Client applications are expected to know what they are doing when invoking this function. Most drivers simply do not implement file attachments.

  FT_EXPORT( FT_Error )
  FT_Attach_Stream( FT_Face        face,
                    FT_Open_Args*  parameters );

This function is similar to FT_Attach_File() with the exception that it reads the attachment from an arbitrary stream.

FreeType error code. 0 means success.

The meaning of the `attach' (i.e. what really happens when the new file is read) is not fixed by FreeType itself. It really depends on the font format (and thus the font driver).

Client applications are expected to know what they are doing when invoking this function. Most drivers simply do not implement file attachments.

  FT_EXPORT( FT_Error )
  FT_Set_Char_Size( FT_Face     face,
                    FT_F26Dot6  char_width,
                    FT_F26Dot6  char_height,
                    FT_UInt     horz_resolution,
                    FT_UInt     vert_resolution );

Sets the character dimensions of a given face object. The `char_width' and `char_height' values are used for the width and height, respectively, expressed in 26.6 fractional points.

If the horizontal or vertical resolution values are zero, a default value of 72dpi is used. Similarly, if one of the character dimensions is zero, its value is set equal to the other.

FreeType error code. 0 means success.

When dealing with fixed-size faces (i.e., non-scalable formats), use the function FT_Set_Pixel_Sizes().

  FT_EXPORT( FT_Error )
  FT_Set_Pixel_Sizes( FT_Face  face,
                      FT_UInt  pixel_width,
                      FT_UInt  pixel_height );

Sets the character dimensions of a given face object. The width and height are expressed in integer pixels.

If one of the character dimensions is zero, its value is set equal to the other.

FreeType error code. 0 means success.

The values of `pixel_width' and `pixel_height' correspond to the pixel values of the _typographic_ character size, which are NOT necessarily the same as the dimensions of the glyph `bitmap cells'.

The `character size' is really the size of an abstract square called the `EM', used to design the font. However, depending on the font design, glyphs will be smaller or greater than the EM.

This means that setting the pixel size to, say, 8x8 doesn't guarantee in any way that you will get glyph bitmaps that all fit within an 8x8 cell (sometimes even far from it).

  FT_EXPORT( void )
  FT_Set_Transform( FT_Face     face,
                    FT_Matrix*  matrix,
                    FT_Vector*  delta );

A function used to set the transformation that is applied to glyph images just before they are converted to bitmaps in a glyph slot when FT_Render_Glyph() is called.

The transformation is only applied to scalable image formats after the glyph has been loaded. It means that hinting is unaltered by the transformation and is performed on the character size given in the last call to FT_Set_Char_Sizes() or FT_Set_Pixel_Sizes().

  FT_EXPORT( FT_Error )
  FT_Load_Glyph( FT_Face  face,
                 FT_UInt  glyph_index,
                 FT_Int   load_flags );

A function used to load a single glyph within a given glyph slot, for a given size.

FreeType error code. 0 means success.

If the glyph image is not a bitmap, and if the bit flag FT_LOAD_IGNORE_TRANSFORM is unset, the glyph image will be transformed with the information passed to a previous call to FT_Set_Transform().

Note that this also transforms the `face.glyph.advance' field, but *not* the values in `face.glyph.metrics'.

  FT_EXPORT( FT_UInt )
  FT_Get_Char_Index( FT_Face   face,
                     FT_ULong  charcode );

Returns the glyph index of a given character code. This function uses a charmap object to do the translation.

The glyph index. 0 means `undefined character code'.

FreeType computes its own glyph indices which are not necessarily the same as used in the font in case the font is based on glyph indices. Reason for this behaviour is to assure that index 0 is never used, representing the missing glyph.

  FT_EXPORT( FT_UInt )
  FT_Get_Name_Index( FT_Face     face,
                     FT_String*  glyph_name );

Returns the glyph index of a given glyph name. This function uses driver specific objects to do the translation.

The glyph index. 0 means `undefined character code'.

  FT_EXPORT( FT_Error )
  FT_Load_Char( FT_Face   face,
                FT_ULong  char_code,
                FT_Int    load_flags );

A function used to load a single glyph within a given glyph slot, for a given size, according to its character code.

FreeType error code. 0 means success.

If the face has no current charmap, or if the character code is not defined in the charmap, this function will return an error.

If the glyph image is not a bitmap, and if the bit flag FT_LOAD_IGNORE_TRANSFORM is unset, the glyph image will be transformed with the information passed to a previous call to FT_Set_Transform().

Note that this also transforms the `face.glyph.advance' field, but *not* the values in `face.glyph.metrics'.

#define FT_LOAD_DEFAULT  0

A bit-field constant, used with FT_Load_Glyph() to indicate that the function should try to load the glyph normally, i.e., embedded bitmaps are favored over outlines, vectors are always scaled and grid-fitted.

#define FT_LOAD_RENDER  4

A bit-field constant, used with FT_Load_Glyph() to indicate that the function should load the glyph and immediately convert it into a bitmap, if necessary, by calling FT_Render_Glyph().

Note that by default, FT_Load_Glyph() loads the glyph image in its native format.

#define FT_LOAD_MONOCHROME  4096

Only used with FT_LOAD_RENDER set, it indicates that the returned glyph image should be 1-bit monochrome. This really tells the glyph loader to use `ft_render_mode_mono' when calling FT_Render_Glyph().

#define FT_LOAD_LINEAR_DESIGN  8192

A bit-field constant, used with FT_Load_Glyph() to indicate that the function should return the linearly scaled metrics expressed in original font units, instead of the default 16.16 pixel values.

#define FT_LOAD_NO_SCALE  1

A bit field constant, used with FT_Load_Glyph() to indicate that the vector outline being loaded should not be scaled to 26.6 fractional pixels, but kept in notional units.

#define FT_LOAD_NO_HINTING  2

A bit-field constant, used with FT_Load_Glyph() to indicate that the vector outline being loaded should not be fitted to the pixel grid but simply scaled to 26.6 fractional pixels.

This flag is ignored if FT_LOAD_NO_SCALE is set.

#define FT_LOAD_NO_BITMAP  8

A bit-field constant, used with FT_Load_Glyph() to indicate that the function should not load the bitmap or pixmap of a given glyph. This is useful when you do not want to load the embedded bitmaps of scalable formats, as the native glyph image will be loaded, and can then be rendered through FT_Render_Glyph().

#define FT_LOAD_CROP_BITMAP  64

A bit-field constant, used with FT_Load_Glyph() to indicate that the font driver should try to crop the bitmap (i.e. remove all space around its black bits) when loading it. For now, this really only works with embedded bitmaps in TrueType fonts.

#define FT_LOAD_VERTICAL_LAYOUT  16

A bit-field constant, used with FT_Load_Glyph() to indicate that the glyph image should be prepared for vertical layout. This basically means that `face.glyph.advance' will correspond to the vertical advance height (instead of the default horizontal advance width), and that the glyph image will translated to match the vertical bearings positions.

#define FT_LOAD_IGNORE_TRANSFORM  2048

A bit-field constant, used with FT_Load_Glyph() to indicate that the glyph loader should not try to transform the loaded glyph image.

#define FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH  512

A bit-field constant, used with FT_Load_Glyph() to indicate that the glyph loader should ignore the global advance width defined in the font. As far as we know, this is only used by the X-TrueType font server, in order to deal correctly with the incorrect metrics contained in DynaLab's TrueType CJK fonts.

#define FT_LOAD_FORCE_AUTOHINT  32

A bit-field constant, used with FT_Load_Glyph() to indicate that the function should try to auto-hint the glyphs, even if a driver specific hinter is available.

#define FT_LOAD_NO_RECURSE  1024

A bit-field constant, used with FT_Load_Glyph() to indicate that the glyph loader should not load composite glyph recursively. Rather, when a composite glyph is encountered, it should set the values of `num_subglyphs' and `subglyphs', as well as set `face->glyph.format' to ft_glyph_format_composite.

This is for use by the auto-hinter and possibly other tools. For nearly all applications, this flags should be left unset when invoking FT_Load_Glyph().

Note that the flag forces the load of unscaled glyphs.

#define FT_LOAD_PEDANTIC  128

A bit-field constant, used with FT_Load_Glyph() to indicate that the glyph loader should perform a pedantic bytecode interpretation. Many popular fonts come with broken glyph programs. When this flag is set, loading them will return an error. Otherwise, errors are ignored by the loader, sometimes resulting in ugly glyphs.

  FT_EXPORT( FT_Error )
  FT_Render_Glyph( FT_GlyphSlot  slot,
                   FT_UInt       render_mode );

Converts a given glyph image to a bitmap. It does so by inspecting the glyph image format, find the relevant renderer, and invoke it.

FreeType error code. 0 means success.

  typedef enum  FT_Render_Mode_
  {
    ft_render_mode_normal = 0,
    ft_render_mode_mono   = 1

  } FT_Render_Mode;

An enumeration type that lists the render modes supported by the FreeType 2 renderer(s). A renderer is in charge of converting a glyph image into a bitmap.

There is no render mode to produce 8-bit `monochrome' bitmaps -- you have to make the conversion yourself if you need such things (besides, FreeType is not a graphics library).

More modes might appear later for specific display modes (e.g. TV, LCDs, etc.). They will be supported through the simple addition of a renderer module, with no changes to the rest of the engine.

  FT_EXPORT( FT_Error )
  FT_Get_Kerning( FT_Face     face,
                  FT_UInt     left_glyph,
                  FT_UInt     right_glyph,
                  FT_UInt     kern_mode,
                  FT_Vector  *akerning );

Returns the kerning vector between two glyphs of a same face.

FreeType error code. 0 means success.

Only horizontal layouts (left-to-right & right-to-left) are supported by this method. Other layouts, or more sophisticated kernings, are out of the scope of this API function -- they can be implemented through format-specific interfaces.

  typedef enum  FT_Kerning_Mode_
  {
    ft_kerning_default  = 0,
    ft_kerning_unfitted,
    ft_kerning_unscaled

  } FT_Kerning_Mode;

An enumeration used to specify which kerning values to return in FT_Get_Kerning().

  FT_EXPORT( FT_Error )
  FT_Get_Glyph_Name( FT_Face     face,
                     FT_UInt     glyph_index,
                     FT_Pointer  buffer,
                     FT_UInt     buffer_max );

Retrieves the ASCII name of a given glyph in a face. This only works for those faces where FT_HAS_GLYPH_NAME(face) returns true.

FreeType error code. 0 means success.

An error is returned if the face doesn't provide glyph names or if the glyph index is invalid. In all cases of failure, the first byte of `buffer' will be set to 0 to indicate an empty name.

The glyph name is truncated to fit within the buffer if it is too long. The returned string is always zero-terminated.

This function is not compiled within the library if the config macro FT_CONFIG_OPTION_NO_GLYPH_NAMES is defined in `include/freetype/config/ftoptions.h'

  FT_EXPORT( const char* )
  FT_Get_Postscript_Name( FT_Face  face );

Retrieves the ASCII Postscript name of a given face, if available. This should only work with Postscript and TrueType fonts.

A pointer to the face's Postscript name. NULL if un-available.

The returned pointer is owned by the face and will be destroyed with it.

  typedef struct  FT_CharMapRec_
  {
    FT_Face      face;
    FT_Encoding  encoding;
    FT_UShort    platform_id;
    FT_UShort    encoding_id;

  } FT_CharMapRec;

The base charmap structure.

  FT_EXPORT( FT_Error )
  FT_Select_Charmap( FT_Face      face,
                     FT_Encoding  encoding );

Selects a given charmap by its encoding tag (as listed in `freetype.h').

FreeType error code. 0 means success.

This function will return an error if no charmap in the face corresponds to the encoding queried here.

  FT_EXPORT( FT_Error )
  FT_Set_Charmap( FT_Face     face,
                  FT_CharMap  charmap );

Selects a given charmap for character code to glyph index decoding.

FreeType error code. 0 means success.

This function will return an error if the charmap is not part of the face (i.e., if it is not listed in the face->charmaps[] table).

  typedef struct FT_ModuleRec_*  FT_Module;

A handle to a given FreeType module object. Each module can be a font driver, a renderer, or anything else that provides services to the formers.

  typedef struct FT_DriverRec_*  FT_Driver;

A handle to a given FreeType font driver object. Each font driver is a special module capable of creating faces from font files.

  typedef struct FT_RendererRec_*  FT_Renderer;

A handle to a given FreeType renderer. A renderer is a special module in charge of converting a glyph image to a bitmap, when necessary. Each renderer supports a given glyph image format, and one or more target surface depths.

#ifndef FT_ENC_TAG
#define FT_ENC_TAG( value, _x1, _x2, _x3, _x4 ) \
        value = ( ( (unsigned long)_x1 << 24 ) | \
                  ( (unsigned long)_x2 << 16 ) | \
                  ( (unsigned long)_x3 << 8  ) | \
                    (unsigned long)_x4         )
#endif /* FT_ENC_TAG */

This macro converts four letter tags into an unsigned long. It is used to define "encoding" identifiers (see FT_Encoding )

  typedef struct FT_Face_InternalRec_*  FT_Face_Internal;

An opaque handle to an FT_Face_InternalRec structure, used to model private data of a given FT_Face object.

This structure might change between releases of FreeType 2 and are not generally available to client applications.

#define FT_HAS_HORIZONTAL( face ) \
          ( face->face_flags & FT_FACE_FLAG_HORIZONTAL )

A macro that returns true whenever a face object contains horizontal metrics (this is true for all font formats though).

#define FT_HAS_VERTICAL( face ) \
          ( face->face_flags & FT_FACE_FLAG_VERTICAL )

A macro that returns true whenever a face object contains vertical metrics.

#define FT_HAS_KERNING( face ) \
          ( face->face_flags & FT_FACE_FLAG_KERNING )

A macro that returns true whenever a face object contains kerning data that can be accessed with FT_Get_Kerning .

#define FT_IS_SCALABLE( face ) \
          ( face->face_flags & FT_FACE_FLAG_SCALABLE )

A macro that returns true whenever a face object contains a scalable font face (true for TrueType, Type 1, CID, and OpenType/CFF font formats.

#define FT_IS_SFNT( face ) \
          ( face->face_flags & FT_FACE_FLAG_SFNT )

A macro that returns true whenever a face object contains a font whose format is based on the SFNT storage scheme. This usually means: TrueType fonts, OpenType fonts, as well as SFNT-based embedded bitmap fonts.

If this macro is true, all functions defined in FT_SFNT_NAMES_H and FT_TRUETYPE_TABLES_H are available.

#define FT_IS_FIXED_WIDTH( face ) \
          ( face->face_flags & FT_FACE_FLAG_FIXED_WIDTH )

A macro that returns true whenever a face object contains a font face that contains fixed-width (or "monospace", "fixed-pitch", etc.) glyphs.

#define FT_HAS_FIXED_SIZES( face ) \
          ( face->face_flags & FT_FACE_FLAG_FIXED_SIZES )

A macro that returns true whenever a face object contains some embedded bitmaps. See the `fixed_sizes' field of the FT_FaceRec structure.

#define FT_HAS_FAST_GLYPHS( face ) \
          ( face->face_flags & FT_FACE_FLAG_FAST_GLYPHS )

Deprecated, indicates that the face contains so-called "fast" glyph bitmaps.

#define FT_HAS_GLYPH_NAMES( face ) \
          ( face->face_flags & FT_FACE_FLAG_GLYPH_NAMES )

A macro that returns true whenever a face object contains some glyph names that can be accessed through ?FT_Get_Glyph_Names.

#define FT_HAS_MULTIPLE_MASTERS( face ) \
          ( face->face_flags & FT_FACE_FLAG_MULTIPLE_MASTERS )

A macro that returns true whenever a face object contains some multiple masters. The functions provided by FT_MULTIPLE_MASTERS_H are then available to choose the exact design you want.

  typedef struct FT_Size_InternalRec_*  FT_Size_Internal;

An opaque handle to an FT_Size_InternalRec structure, used to model private data of a given FT_Size object.

  typedef struct FT_Slot_InternalRec_*  FT_Slot_Internal;

An opaque handle to an FT_Slot_InternalRec structure, used to model private data of a given FT_GlyphSlot object.

  FT_EXPORT( FT_ULong )
  FT_Get_First_Char( FT_Face   face,
                     FT_UInt  *agindex );

This function is used to return the first character code in the current charmap of a given face. It will also return the corresponding glyph index.

The charmap's first character code.

You should use this function with FT_Get_Next_Char to be able to parse all character codes available in a given charmap. The code should look like this:

 
      FT_ULong  charcode; 
      FT_UInt   gindex; 


      charcode = FT_Get_First_Char( face, &gindex ); 
      while ( gindex != 0 ) 
      { 
        ... do something with (charcode,gindex) pair ... 

        charcode = FT_Get_Next_Char( face, charcode, &gindex ); 
      } 

Note that `*agindex' will be set to 0 if the charmap is empty. The result itself can be 0 in two cases: if the charmap is empty or when the value 0 is the first valid character code.

  FT_EXPORT( FT_ULong )
  FT_Get_Next_Char( FT_Face    face,
                    FT_ULong   char_code,
                    FT_UInt   *agindex );

This function is used to return the next character code in the current charmap of a given face following the value 'char_code', as well as the corresponding glyph index.

The charmap's next character code.

You should use this function with FT_Get_First_Char to walk through all character codes available in a given charmap. See the note for this function for a simple code example.

Note that `*agindex' will be set to 0 when there are no more codes in the charmap.