freetype.h

qt-embedded-2.3.8.tar.gz源码

  /*                                                                       */
#define FT_STYLE_FLAG_BOLD  2


  /*************************************************************************/
  /*                                                                       */
  /* <Type>                                                                */
  /*    FT_Size_Internal                                                   */
  /*                                                                       */
  /* <Description>                                                         */
  /*    An opaque handle to an FT_Size_InternalRec structure, used to      */
  /*    model private data of a given FT_Size object.                      */
  /*                                                                       */
  typedef struct FT_Size_InternalRec_*  FT_Size_Internal;

  
  /*************************************************************************/
  /*                                                                       */
  /*                    FreeType base size metrics                         */
  /*                                                                       */
  /* <Struct>                                                              */
  /*    FT_Size_Metrics                                                    */
  /*                                                                       */
  /* <Description>                                                         */
  /*    The size metrics structure returned scaled important distances for */
  /*    a given size object.                                               */
  /*                                                                       */
  /* <Fields>                                                              */
  /*    x_ppem       :: The character width, expressed in integer pixels.  */
  /*                    This is the width of the EM square expressed in    */
  /*                    pixels, hence the term `ppem' (pixels per EM).     */
  /*                                                                       */
  /*    y_ppem       :: The character height, expressed in integer pixels. */
  /*                    This is the height of the EM square expressed in   */
  /*                    pixels, hence the term `ppem' (pixels per EM).     */
  /*                                                                       */
  /*    x_scale      :: A simple 16.16 fixed point format coefficient used */
  /*                    to scale horizontal distances expressed in font    */
  /*                    units to fractional (26.6) pixel coordinates.      */
  /*                                                                       */
  /*    y_scale      :: A simple 16.16 fixed point format coefficient used */
  /*                    to scale vertical distances expressed in font      */
  /*                    units to fractional (26.6) pixel coordinates.      */
  /*                                                                       */
  /*    ascender     :: The ascender, expressed in 26.6 fixed point        */
  /*                    pixels.  Always positive.                          */
  /*                                                                       */
  /*    descender    :: The descender, expressed in 26.6 fixed point       */
  /*                    pixels.  Always positive.                          */
  /*                                                                       */
  /*    height       :: The text height, expressed in 26.6 fixed point     */
  /*                    pixels.  Always positive.                          */
  /*                                                                       */
  /*    max_advance  :: Maximum horizontal advance, expressed in 26.6      */
  /*                    fixed point pixels.  Always positive.              */
  /*                                                                       */
  /* <Note>                                                                */
  /*    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_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;


  /*************************************************************************/
  /*                                                                       */
  /*                       FreeType base size class                        */
  /*                                                                       */
  /* <Struct>                                                              */
  /*    FT_SizeRec                                                         */
  /*                                                                       */
  /* <Description>                                                         */
  /*    FreeType root size class structure.  A size object models the      */
  /*    resolution and pointsize dependent data of a given face.           */
  /*                                                                       */
  /* <Fields>                                                              */
  /*    face    :: Handle to the parent face object.                       */
  /*                                                                       */
  /*    generic :: A typeless pointer, which is unused by the FreeType     */
  /*               library or any of its drivers.  It can be used by       */
  /*               client applications to link their own data to each size */
  /*               object.                                                 */
  /*                                                                       */
  /*    metrics :: Metrics for this size object.  This field is read-only. */
  /*                                                                       */
  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;


  /*************************************************************************/
  /*                                                                       */
  /* <Struct>                                                              */
  /*    FT_SubGlyph                                                        */
  /*                                                                       */
  /* <Description>                                                         */
  /*    The subglyph structure is an internal object used to describe      */
  /*    subglyphs (for example, in the case of composites).                */
  /*                                                                       */
  /* <Note>                                                                */
  /*    The subglyph implementation is not part of the high-level API,     */
  /*    hence the forward structure declaration.                           */
  /*                                                                       */
  typedef struct FT_SubGlyph_  FT_SubGlyph;


  /*************************************************************************/
  /*                                                                       */
  /* <Type>                                                                */
  /*    FT_Slot_Internal                                                   */
  /*                                                                       */
  /* <Description>                                                         */
  /*    An opaque handle to an FT_Slot_InternalRec structure, used to      */
  /*    model private data of a given FT_GlyphSlot object.                 */
  /*                                                                       */
  typedef struct FT_Slot_InternalRec_*  FT_Slot_Internal;


  /*************************************************************************/
  /*                                                                       */
  /*                  FreeType Glyph Slot base class                       */
  /*                                                                       */
  /* <Struct>                                                              */
  /*    FT_GlyphSlotRec                                                    */
  /*                                                                       */
  /* <Description>                                                         */
  /*    FreeType root glyph slot class structure.  A glyph slot is a       */
  /*    container where individual glyphs can be loaded, be they           */
  /*    vectorial or bitmap/graymaps.                                      */
  /*                                                                       */
  /* <Fields>                                                              */
  /*    library           :: A handle to the FreeType library instance     */
  /*                         this slot belongs to.                         */
  /*                                                                       */
  /*    face              :: A handle to the parent face object.           */
  /*                                                                       */
  /*    next              :: In some cases (like some font tools), several */
  /*                         glyph slots per face object can be a good     */
  /*                         thing.  As this is rare, the glyph slots are  */
  /*                         listed through a direct, single-linked list   */
  /*                         using its `next' field.                       */
  /*                                                                       */
  /*    generic           :: A typeless pointer which is unused by the     */
  /*                         FreeType library or any of its drivers.  It   */
  /*                         can be used by client applications to link    */
  /*                         their own data to each size object.           */
  /*                                                                       */
  /*    metrics           :: The metrics of the last loaded glyph in the   */
  /*                         slot.  The returned values depend on the last */
  /*                         load flags (see the FT_Load_Glyph() API       */
  /*                         function) and can be expressed either in 26.6 */
  /*                         fractional pixels or font units.              */
  /*                                                                       */
  /*                         Note that even when the glyph image is        */
  /*                         transformed, the metrics are not.             */
  /*                                                                       */
  /*    linearHoriAdvance :: For scalable formats only, this field holds   */
  /*                         the linearly scaled horizontal advance width  */
  /*                         for the glyph (i.e. the scaled and unhinted   */
  /*                         value of the hori advance).  This can be      */
  /*                         important to perform correct WYSIWYG layout.  */
  /*                                                                       */
  /*                         Note that this value is expressed by default  */
  /*                         in 16.16 pixels. However, when the glyph is   */
  /*                         loaded with the FT_LOAD_LINEAR_DESIGN flag,   */
  /*                         this field contains simply the value of the   */
  /*                         advance in original font units.               */
  /*                                                                       */
  /*    linearVertAdvance :: For scalable formats only, this field holds   */
  /*                         the linearly scaled vertical advance height   */
  /*                         for the glyph.  See linearHoriAdvance for     */
  /*                         comments.                                     */
  /*                                                                       */
  /*    advance           :: This is the transformed advance width for the */
  /*                         glyph.                                        */
  /*                                                                       */
  /*    format            :: This field indicates the format of the image  */
  /*                         contained in the glyph slot.  Typically       */
  /*