/******************************************************************* * *  ftxwidth.c                                                  1.0 * *    Glyph Widths (and Heights) fast retrieval extension * *  Copyright 1996-2001 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. * * *  This extension is used to parse the "glyf" table of a TrueType *  file in order to extract the bbox of a given range of glyphs. * *  The bbox is then used to build font unit widths and height *  that are returned in two parallel arrays. * *  This extension is needed by the FreeType/2 OS/2 Font Driver. * ******************************************************************/#include "ftxwidth.h"#include "ttdebug.h"#include "ttobjs.h"#include "ttfile.h"#include "tttags.h"#include "ttload.h"/* Required by the tracing mode */#undef  TT_COMPONENT#define TT_COMPONENT  trace_any  /******************************************************************/  /*                                                                */  /*  Function:  TT_Get_Face_Widths                                 */  /*                                                                */  /*  Description: Returns the widths and/or heights of a given     */  /*               range of glyphs for a face.                      */  /*                                                                */  /*  Input:                                                        */  /*     face        ::  face handle                                */  /*                                                                */  /*     first_glyph ::  first glyph in range                       */  /*                                                                */  /*     last_glyph  ::  last glyph in range                        */  /*                                                                */  /*     widths      ::  address of table receiving the widths      */  /*                     expressed in font units (ushorts). Set     */  /*                     this parameter to NULL if you're not       */  /*                     interested by these values.                */  /*                                                                */  /*     heights     ::  address of table receiving the heights     */  /*                     expressed in font units (ushorts).  Set    */  /*                     this parameter to NULL if you're not       */  /*                     interested by these values.                */  /*                                                                */  /*  Returns:                                                      */  /*       Error code                                               */  /*                                                                */  /*                                                                */  /******************************************************************/  FT_EXPORT_FUNC( TT_Error )  TT_Get_Face_Widths( TT_Face     face,                      TT_UShort   first_glyph,                      TT_UShort   last_glyph,                      TT_UShort*  widths,                      TT_UShort*  heights )  {    DEFINE_ALL_LOCALS;    PFace     faze = HANDLE_Face(face);    UShort    n;    Long      table;    ULong     glyf_offset;      /* offset of glyph table in file */    UShort    zero_width  = 0;  /* width of glyph 0  */    UShort    zero_height = 0;  /* height of glyph 0 */    Bool      zero_loaded = 0;#ifndef TT_HUGE_PTR    PStorage  locations;#else    Storage TT_HUGE_PTR * locations;#endif    TT_BBox   bbox;    if ( !faze )      return TT_Err_Invalid_Face_Handle;    if ( last_glyph >= faze->numGlyphs ||         first_glyph > last_glyph      )      return TT_Err_Invalid_Argument;    /* find "glyf" table */    table = TT_LookUp_Table( faze, TTAG_glyf );    if ( table < 0 )    {      PERROR(( "ERROR: there is no glyph table in this font file!\n" ));      return TT_Err_Glyf_Table_Missing;    }    glyf_offset = faze->dirTables[table].Offset;    /* now access stream */    if ( USE_Stream( faze->stream, stream ) )      return error;    locations = faze->glyphLocations + first_glyph;    /* loop to load each glyph in the range */    for ( n = first_glyph; n <= last_glyph; n++ )    {      if ( n + 1 < faze->numGlyphs &&           locations[0] == locations[1] )      {        /* Note : Glyph 0 is always used to indicate a missing glyph   */        /*        in a range. We must thus return its width and height */        /*        where appropriate when we find an undefined glyph.   */        if ( zero_loaded == 0 )        {          if ( FILE_Seek( glyf_offset + faze->glyphLocations[0] ) ||               ACCESS_Frame( 10L ) )            goto Fail;          (void)GET_Short();   /* skip number of contours */          bbox.xMin = GET_Short();          bbox.yMin = GET_Short();          bbox.xMax = GET_Short();          bbox.yMax = GET_Short();          FORGET_Frame();          zero_width  = (UShort)(bbox.xMax - bbox.xMin);          zero_height = (UShort)(bbox.yMax - bbox.yMin);          zero_loaded = 1;        }        if ( widths )          *widths++  = zero_width;        if ( heights )          *heights++ = zero_height;      }      else      {        /* normal glyph, read header */        if ( FILE_Seek( glyf_offset + locations[0] ) ||             ACCESS_Frame( 10L ) )          goto Fail;        (void)GET_Short();  /* skip number of contours */        bbox.xMin = GET_Short();        bbox.yMin = GET_Short();        bbox.xMax = GET_Short();        bbox.yMax = GET_Short();        FORGET_Frame();        if ( widths )          *widths++  = (UShort)(bbox.xMax - bbox.xMin);        if ( heights )          *heights++ = (UShort)(bbox.yMax - bbox.yMin);      }    }  Fail:    DONE_Stream( stream );    return error;  }/* END */