z1gload.c

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Author : David Turner
Date : 2000-07-20 03:44:50
Hash : c49f69cb
Message : some welcome fixes related to the auto-hinter: - removed a stupid memory leak - fixed the weird metrics hinting (the horizontal edges were used, instead of the vertical one, to compute the metrics adjustments, silly, silly, silly). there is still some bugs that I'm looking at though, but we're very near the release..
src/type1z/z1gload.c
/***************************************************************************/
/*                                                                         */
/*  z1gload.c                                                              */
/*                                                                         */
/*    Experimental Type 1 Glyph Loader (body).                             */
/*                                                                         */
/*  Copyright 1996-2000 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.                                        */
/*                                                                         */
/***************************************************************************/


#ifdef FT_FLAT_COMPILE

#include "z1gload.h"

#else

#include <type1z/z1gload.h>

#endif


#include <freetype/internal/ftdebug.h>
#include <freetype/internal/ftstream.h>
#include <freetype/ftoutln.h>

#include <string.h>     /* for strcmp() */


  /*************************************************************************/
  /*                                                                       */
  /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
  /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
  /* messages during execution.                                            */
  /*                                                                       */
#undef  FT_COMPONENT
#define FT_COMPONENT  trace_z1gload


  typedef enum  Z1_Operator_
  {
    op_none = 0,
    op_endchar,
    op_hsbw,
    op_seac,
    op_sbw,
    op_closepath,
    op_hlineto,
    op_hmoveto,
    op_hvcurveto,
    op_rlineto,
    op_rmoveto,
    op_rrcurveto,
    op_vhcurveto,
    op_vlineto,
    op_vmoveto,
    op_dotsection,
    op_hstem,
    op_hstem3,
    op_vstem,
    op_vstem3,
    op_div,
    op_callothersubr,
    op_callsubr,
    op_pop,
    op_return,
    op_setcurrentpoint,

    op_max    /* never remove this one */

  } Z1_Operator;

  static
  const FT_Int  t1_args_count[op_max] =
  {
    0, /* none */
    0, /* endchar */
    2, /* hsbw */
    5, /* seac */
    4, /* sbw */
    0, /* closepath */
    1, /* hlineto */
    1, /* hmoveto */
    4, /* hvcurveto */
    2, /* rlineto */
    2, /* rmoveto */
    6, /* rrcurveto */
    4, /* vhcurveto */
    1, /* vlineto */
    1, /* vmoveto */
    0, /* dotsection */
    2, /* hstem */
    6, /* hstem3 */
    2, /* vstem */
    6, /* vstem3 */
    2, /* div */
   -1, /* callothersubr */
    1, /* callsubr */
    0, /* pop */
    0, /* return */
    2  /* setcurrentpoint */
  };


  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/
  /**********                                                      *********/
  /**********                                                      *********/
  /**********             GENERIC CHARSTRING PARSING               *********/
  /**********                                                      *********/
  /**********                                                      *********/
  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    Z1_Init_Builder                                                    */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Initializes a given glyph builder.                                 */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    builder :: A pointer to the glyph builder to initialize.           */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face    :: The current face object.                                */
  /*                                                                       */
  /*    size    :: The current size object.                                */
  /*                                                                       */
  /*    glyph   :: The current glyph object.                               */
  /*                                                                       */
  LOCAL_FUNC
  void  Z1_Init_Builder( Z1_Builder*   builder,
                         T1_Face       face,
                         Z1_Size       size,
                         Z1_GlyphSlot  glyph )
  {
    builder->path_begun  = 0;
    builder->load_points = 1;

    builder->face   = face;
    builder->glyph  = glyph;
    builder->memory = face->root.memory;

    if ( glyph )
    {
      FT_GlyphLoader*  loader = glyph->root.loader;


      builder->loader  = loader;
      builder->current = &loader->current.outline;
      builder->base    = &loader->base.outline;

      FT_GlyphLoader_Rewind( loader );
    }

    if ( size )
    {
      builder->scale_x = size->root.metrics.x_scale;
      builder->scale_y = size->root.metrics.y_scale;
    }

    builder->pos_x = 0;
    builder->pos_y = 0;

    builder->left_bearing.x = 0;
    builder->left_bearing.y = 0;
    builder->advance.x      = 0;
    builder->advance.y      = 0;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    Z1_Done_Builder                                                    */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Finalizes a given glyph builder.  Its contents can still be used   */
  /*    after the call, but the function saves important information       */
  /*    within the corresponding glyph slot.                               */
  /*                                                                       */
  /* <Input>                                                               */
  /*    builder :: A pointer to the glyph builder to finalize.             */
  /*                                                                       */
  LOCAL_FUNC
  void Z1_Done_Builder( Z1_Builder*  builder )
  {
    Z1_GlyphSlot  glyph = builder->glyph;


    if ( glyph )
      glyph->root.outline = *builder->base;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    Z1_Init_Decoder                                                    */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Initializes a given glyph decoder.                                 */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    decoder :: A pointer to the glyph builder to initialize.           */
  /*                                                                       */
  LOCAL_FUNC
  void  Z1_Init_Decoder( Z1_Decoder* decoder )
  {
    decoder->top              = 0;
    decoder->zone             = 0;
    decoder->flex_state       = 0;
    decoder->num_flex_vectors = 0;
    decoder->blend            = 0;

    /* Clear loader */
    MEM_Set( &decoder->builder, 0, sizeof ( decoder->builder ) );
  }


  /* check that there is enough space for `count' more points */
  static
  FT_Error  check_points( Z1_Builder*  builder,
                          FT_Int       count )
  {
    return FT_GlyphLoader_Check_Points( builder->loader, count, 0 );
  }


  /* add a new point; do not check space */
  static
  void  add_point( Z1_Builder*  builder,
                   FT_Pos       x,
                   FT_Pos       y,
                   FT_Byte      flag )
  {
    FT_Outline*  outline = builder->current;


    if ( builder->load_points )
    {
      FT_Vector*  point   = outline->points + outline->n_points;
      FT_Byte*    control = (FT_Byte*)outline->tags + outline->n_points;


      point->x = x;
      point->y = y;
      *control = flag ? FT_Curve_Tag_On : FT_Curve_Tag_Cubic;

      builder->last = *point;
    }

    outline->n_points++;
  }


  /* check space for a new on-curve point, then add it */
  static
  FT_Error  add_point1( Z1_Builder*  builder,
                        FT_Pos       x,
                        FT_Pos       y )
  {
    FT_Error  error;


    error = check_points( builder, 1 );
    if ( !error )
      add_point( builder, x, y, 1 );

    return error;
  }


  /* check space for a new contour, then add it */
  static
  FT_Error  add_contour( Z1_Builder*  builder )
  {
    FT_Outline*  outline = builder->current;
    FT_Error     error;


    if ( !builder->load_points )
    {
      outline->n_contours++;
      return FT_Err_Ok;
    }

    /* reallocate contours array if necessary */
    error = FT_GlyphLoader_Check_Points( builder->loader, 0, 1 );
    if ( !error )
    {
      if ( outline->n_contours > 0 )
        outline->contours[outline->n_contours - 1] = outline->n_points - 1;

      outline->n_contours++;
    }

    return error;
  }


  /* if a path was begun, add its first on-curve point */
  static
  FT_Error  start_point( Z1_Builder*  builder,
                         FT_Pos       x,
                         FT_Pos       y )
  {
    /* test whether we are building a new contour */
    if ( !builder->path_begun )
    {
      FT_Error  error;


      builder->path_begun = 1;
      error = add_contour( builder );
      if ( error )
        return error;
    }
    return add_point1( builder, x, y );
  }


  /* close the current contour */
  static
  void  close_contour( Z1_Builder*  builder )
  {
    FT_Outline*  outline = builder->current;


    /* XXX: we must not include the last point in the path if it */
    /*      is located on the first point                        */
    if ( outline->n_points > 1 )
    {
      FT_Int      first = 0;
      FT_Vector*  p1    = outline->points + first;
      FT_Vector*  p2    = outline->points + outline->n_points-1;


      if ( outline->n_contours > 1 )
      {
        first = outline->contours[outline->n_contours - 2] + 1;
        p1    = outline->points + first;
      }

      if ( p1->x == p2->x && p1->y == p2->y )
        outline->n_points--;
    }

    if ( outline->n_contours > 0 )
      outline->contours[outline->n_contours - 1] = outline->n_points - 1;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    lookup_glyph_by_stdcharcode                                        */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Looks up a given glyph by its StandardEncoding charcode.  Used     */
  /*    to implement the SEAC Type 1 operator.                             */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face     :: The current face object.                               */
  /*                                                                       */
  /*    charcode :: The character code to look for.                        */
  /*                                                                       */
  /* <Return>                                                              */
  /*    A glyph index in the font face.  Returns -1 if the corresponding   */
  /*    glyph wasn't found.                                                */
  /*                                                                       */
  static
  FT_Int  lookup_glyph_by_stdcharcode( T1_Face  face,
                                       FT_Int   charcode )
  {
    FT_Int              n;
    const FT_String*    glyph_name;
    PSNames_Interface*  psnames = (PSNames_Interface*)face->psnames;


    /* check range of standard char code */
    if ( charcode < 0 || charcode > 255 )
      return -1;

    glyph_name = psnames->adobe_std_strings(
                   psnames->adobe_std_encoding[charcode]);

    for ( n = 0; n < face->type1.num_glyphs; n++ )
    {
      FT_String*  name = (FT_String*)face->type1.glyph_names[n];


      if ( name && strcmp( name,glyph_name ) == 0 )
        return n;
    }

    return -1;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    t1operator_seac                                                    */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Implements the `seac' Type 1 operator for a Type 1 decoder.        */
  /*                                                                       */
  /* <Input>                                                               */
  /*    decoder :: The current CID decoder.                                */
  /*                                                                       */
  /*    asb     :: The accent's side bearing.                              */
  /*                                                                       */
  /*    adx     :: The horizontal offset of the accent.                    */
  /*                                                                       */
  /*    ady     :: The vertical offset of the accent.                      */
  /*                                                                       */
  /*    bchar   :: The base character's StandardEncoding charcode.         */
  /*                                                                       */
  /*    achar   :: The accent character's StandardEncoding charcode.       */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  static
  FT_Error  t1operator_seac( Z1_Decoder*  decoder,
                             FT_Pos       asb,
                             FT_Pos       adx,
                             FT_Pos       ady,
                             FT_Int       bchar,
                             FT_Int       achar )
  {
    FT_Error     error;
    FT_Int       bchar_index, achar_index, n_base_points;
    FT_Outline*  base = decoder->builder.base;
    FT_Vector    left_bearing, advance;
    T1_Face      face  = decoder->builder.face;
    T1_Font*     type1 = &face->type1;


    bchar_index = lookup_glyph_by_stdcharcode( face, bchar );
    achar_index = lookup_glyph_by_stdcharcode( face, achar );

    if ( bchar_index < 0 || achar_index < 0 )
    {
      FT_ERROR(( "t1operator_seac:" ));
      FT_ERROR(( " invalid seac character code arguments\n" ));
      return T1_Err_Syntax_Error;
    }

    /* if we are trying to load a composite glyph, do not load the */
    /* accent character and return the array of subglyphs.         */
    if ( decoder->builder.no_recurse )
    {
      FT_GlyphSlot     glyph  = (FT_GlyphSlot)decoder->builder.glyph;
      FT_GlyphLoader*  loader = glyph->loader;
      FT_SubGlyph*     subg;


      /* reallocate subglyph array if necessary */
      error = FT_GlyphLoader_Check_Subglyphs( loader, 2 );
      if ( error )
        goto Exit;

      subg = loader->current.subglyphs;

      /* subglyph 0 = base character */
      subg->index = bchar_index;
      subg->flags = FT_SUBGLYPH_FLAG_ARGS_ARE_XY_VALUES |
                    FT_SUBGLYPH_FLAG_USE_MY_METRICS;
      subg->arg1  = 0;
      subg->arg2  = 0;
      subg++;

      /* subglyph 1 = accent character */
      subg->index = achar_index;
      subg->flags = FT_SUBGLYPH_FLAG_ARGS_ARE_XY_VALUES;
      subg->arg1  = adx - asb;
      subg->arg2  = ady;

      /* set up remaining glyph fields */
      glyph->num_subglyphs = 2;
      glyph->subglyphs     = loader->base.subglyphs;
      glyph->format        = ft_glyph_format_composite;

      loader->current.num_subglyphs = 2;
    }

    /* First load `bchar' in builder */
    /* now load the unscaled outline */

    FT_GlyphLoader_Prepare( decoder->builder.loader );  /* prepare loader */

    error = Z1_Parse_CharStrings( decoder,
                                  type1->charstrings    [bchar_index],
                                  type1->charstrings_len[bchar_index],
                                  type1->num_subrs,
                                  type1->subrs,
                                  type1->subrs_len );
    if ( error )
      goto Exit;

    n_base_points = base->n_points;

    /* save the left bearing and width of the base character */
    /* as they will be erased by the next load.              */

    left_bearing = decoder->builder.left_bearing;
    advance      = decoder->builder.advance;

    decoder->builder.left_bearing.x = 0;
    decoder->builder.left_bearing.y = 0;

    /* Now load `achar' on top of */
    /* the base outline           */
    error = Z1_Parse_CharStrings( decoder,
                                  type1->charstrings    [achar_index],
                                  type1->charstrings_len[achar_index],
                                  type1->num_subrs,
                                  type1->subrs,
                                  type1->subrs_len );
    if ( error )
      return error;

    /* restore the left side bearing and   */
    /* advance width of the base character */

    decoder->builder.left_bearing = left_bearing;
    decoder->builder.advance      = advance;

    /* Finally, move the accent */
    if ( decoder->builder.load_points )
    {
      FT_Outline  dummy;


      dummy.n_points = base->n_points - n_base_points;
      dummy.points   = base->points   + n_base_points;
      FT_Outline_Translate( &dummy, adx - asb, ady );
    }

  Exit:
    return error;
  }


#define USE_ARGS( n )  do                            \
                       {                             \
                         top -= n;                   \
                         if ( top < decoder->stack ) \
                           goto Stack_Underflow;     \
                       } while ( 0 )


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    Z1_Parse_CharStrings                                               */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Parses a given Type 1 charstrings program.                         */
  /*                                                                       */
  /* <Input>                                                               */
  /*    decoder         :: The current Type 1 decoder.                     */
  /*                                                                       */
  /*    charstring_base :: The base address of the charstring stream.      */
  /*                                                                       */
  /*    charstring_len  :: The length in bytes of the charstring stream.   */
  /*                                                                       */
  /*    num_subrs       :: The number of sub-routines.                     */
  /*                                                                       */
  /*    subrs_base      :: An array of sub-routines addresses.             */
  /*                                                                       */
  /*    subrs_len       :: An array of sub-routines lengths.               */
  /*                                                                       */
  /* <Return>                                                              */
  /*    Free error code.  0 means success.                                 */
  /*                                                                       */
  LOCAL_FUNC
  FT_Error  Z1_Parse_CharStrings( Z1_Decoder*  decoder,
                                  FT_Byte*     charstring_base,
                                  FT_Int       charstring_len,
                                  FT_Int       num_subrs,
                                  FT_Byte**    subrs_base,
                                  FT_Int*      subrs_len )
  {
    FT_Error          error;
    Z1_Decoder_Zone*  zone;
    FT_Byte*          ip;
    FT_Byte*          limit;
    Z1_Builder*       builder = &decoder->builder;
    FT_Outline*       outline;
    FT_Pos            x, y;


    /* First of all, initialize the decoder */
    decoder->top  = decoder->stack;
    decoder->zone = decoder->zones;
    zone          = decoder->zones;

    builder->path_begun  = 0;

    zone->base           = charstring_base;
    limit = zone->limit  = charstring_base + charstring_len;
    ip    = zone->cursor = zone->base;

    error   = T1_Err_Ok;
    outline = builder->current;

    x = builder->pos_x;
    y = builder->pos_y;

    /* now, execute loop */
    while ( ip < limit )
    {
      FT_Int*      top   = decoder->top;
      Z1_Operator  op    = op_none;
      FT_Long      value = 0;


      /*********************************************************************/
      /*                                                                   */
      /* Decode operator or operand                                        */
      /*                                                                   */
      /*                                                                   */

      /* first of all, decompress operator or value */
      switch ( *ip++ )
      {
      case 1:
        op = op_hstem;
        break;

      case 3:
        op = op_vstem;
        break;
      case 4:
        op = op_vmoveto;
        break;
      case 5:
        op = op_rlineto;
        break;
      case 6:
        op = op_hlineto;
        break;
      case 7:
        op = op_vlineto;
        break;
      case 8:
        op = op_rrcurveto;
        break;
      case 9:
        op = op_closepath;
        break;
      case 10:
        op = op_callsubr;
        break;
      case 11:
        op = op_return;
        break;

      case 13:
        op = op_hsbw;
        break;
      case 14:
        op = op_endchar;
        break;

      case 21:
        op = op_rmoveto;
        break;
      case 22:
        op = op_hmoveto;
        break;

      case 30:
        op = op_vhcurveto;
        break;
      case 31:
        op = op_hvcurveto;
        break;

      case 12:
        if ( ip > limit )
        {
          FT_ERROR(( "Z1_Parse_CharStrings: invalid escape (12+EOF)\n" ));
          goto Syntax_Error;
        }

        switch ( *ip++ )
        {
        case 0:
          op = op_dotsection;
          break;
        case 1:
          op = op_vstem3;
          break;
        case 2:
          op = op_hstem3;
          break;
        case 6:
          op = op_seac;
          break;
        case 7:
          op = op_sbw;
          break;
        case 12:
          op = op_div;
          break;
        case 16:
          op = op_callothersubr;
          break;
        case 17:
          op = op_pop;
          break;
        case 33:
          op = op_setcurrentpoint;
          break;

        default:
          FT_ERROR(( "Z1_Parse_CharStrings: invalid escape (12+%d)\n",
                     ip[-1] ));
          goto Syntax_Error;
        }
        break;

      case 255:    /* four bytes integer */
        if ( ip + 4 > limit )
        {
          FT_ERROR(( "Z1_Parse_CharStrings: unexpected EOF in integer\n" ));
          goto Syntax_Error;
        }

        value = ( (FT_Long)ip[0] << 24 ) |
                ( (FT_Long)ip[1] << 16 ) |
                ( (FT_Long)ip[2] << 8  ) |
                           ip[3];
        ip += 4;
        break;

      default:
        if ( ip[-1] >= 32 )
        {
          if ( ip[-1] < 247 )
            value = (FT_Long)ip[-1] - 139;
          else
          {
            if ( ++ip > limit )
            {
              FT_ERROR(( "Z1_Parse_CharStrings:" ));
              FT_ERROR(( " unexpected EOF in integer\n" ));
              goto Syntax_Error;
            }

          if ( ip[-2] < 251 )
            value =  ( (FT_Long)( ip[-2] - 247 ) << 8 ) + ip[-1] + 108;
          else
            value = -( ( ( (FT_Long)ip[-2] - 251 ) << 8 ) + ip[-1] + 108 );
          }
        }
        else
        {
          FT_ERROR(( "Z1_Parse_CharStrings: invalid byte (%d)\n",
                     ip[-1] ));
          goto Syntax_Error;
        }
      }

      /*********************************************************************/
      /*                                                                   */
      /*  Push value on stack, or process operator                         */
      /*                                                                   */
      /*                                                                   */
      if ( op == op_none )
      {
        if ( top - decoder->stack >= T1_MAX_CHARSTRINGS_OPERANDS )
        {
          FT_ERROR(( "Z1_Parse_CharStrings: stack overflow!\n" ));
          goto Syntax_Error;
        }

        FT_TRACE4(( " %ld", value ));

        *top++       = value;
        decoder->top = top;
      }
      else if ( op == op_callothersubr )  /* callothersubr */
      {
        FT_TRACE4(( " callothersubr" ));

        if ( top - decoder->stack < 2 )
          goto Stack_Underflow;

        top -= 2;
        switch ( top[1] )
        {
        case 1:                     /* start flex feature */
          if ( top[0] != 0 )
            goto Unexpected_OtherSubr;

          decoder->flex_state        = 1;
          decoder->num_flex_vectors  = 0;
          if ( start_point( builder, x, y ) ||
               check_points( builder, 6 )   )
            goto Memory_Error;
          break;

        case 2:                     /* add flex vectors */
          {
            FT_Int  index;

            if ( top[0] != 0 )
              goto Unexpected_OtherSubr;

            /* note that we should not add a point for index 0; */
            /* this will move our current position to the flex  */
            /* point without adding any point to the outline    */
            index = decoder->num_flex_vectors++;
            if ( index > 0 && index < 7 )
              add_point( builder,
                         x,
                         y,
                         (FT_Byte)( index == 3 || index == 6 ) );
          }
          break;

        case 0:                     /* end flex feature */
          if ( top[0] != 3 )
            goto Unexpected_OtherSubr;

          if ( decoder->flex_state       == 0 ||
               decoder->num_flex_vectors != 7 )
          {
            FT_ERROR(( "Z1_Parse_CharStrings: unexpected flex end\n" ));
            goto Syntax_Error;
          }

          /* now consume the remaining `pop pop setcurpoint' */
          if ( ip + 6 > limit ||
               ip[0] != 12 || ip[1] != 17 || /* pop */
               ip[2] != 12 || ip[3] != 17 || /* pop */
               ip[4] != 12 || ip[5] != 33 )  /* setcurpoint */
          {
            FT_ERROR(( "Z1_Parse_CharStrings: invalid flex charstring\n" ));
            goto Syntax_Error;
          }

          ip += 6;
          decoder->flex_state = 0;
          break;

        case 3:                     /* change hints */
          if ( top[0] != 1 )
            goto Unexpected_OtherSubr;

          /* eat the following `pop' */
          if ( ip + 2 > limit )
          {
            FT_ERROR(( "Z1_Parse_CharStrings: invalid escape (12+%d)\n",
                       ip[-1] ));
            goto Syntax_Error;
          }

          if ( ip[0] != 12 || ip[1] != 17 )
          {
            FT_ERROR(( "Z1_Parse_CharStrings:" ));
            FT_ERROR(( " `pop' expected, found (%d %d)\n",
                       ip[0], ip[1] ));
            goto Syntax_Error;
          }
          ip += 2;
          break;

        case 12:
        case 13:
          /* counter control hints, clear stack */
          top = decoder->stack;
          break;

        case 14:
        case 15:
        case 16:
        case 17:
        case 18:                    /* multiple masters */
          {
            T1_Blend*  blend = decoder->blend;
            FT_UInt    num_points, nn, mm;
            FT_Int*    delta;
            FT_Int*    values;


            if ( !blend )
            {
              FT_ERROR(( "Z1_Parse_CharStrings:" ));
              FT_ERROR(( " unexpected multiple masters operator!\n" ));
              goto Syntax_Error;
            }

            num_points = top[1] - 13 + ( top[1] == 18 );
            if ( top[0] != (FT_Int)( num_points * blend->num_designs ) )
            {
              FT_ERROR(( "Z1_Parse_CharStrings:" ));
              FT_ERROR(( " incorrect number of mm arguments\n" ));
              goto Syntax_Error;
            }

            top -= blend->num_designs*num_points;
            if ( top < decoder->stack )
              goto Stack_Underflow;

            /* we want to compute:                                   */
            /*                                                       */
            /*  a0*w0 + a1*w1 + ... + ak*wk                          */
            /*                                                       */
            /* but we only have the a0, a1-a0, a2-a0, .. ak-a0       */
            /* however, given that w0 + w1 + ... + wk == 1, we can   */
            /* rewrite it easily as:                                 */
            /*                                                       */
            /*  a0 + (a1-a0)*w1 + (a2-a0)*w2 + .. + (ak-a0)*wk       */
            /*                                                       */
            /* where k == num_designs-1                              */
            /*                                                       */
            /* I guess that's why it's written in this `compact'     */
            /* form.                                                 */
            /*                                                       */
            delta  = top + num_points;
            values = top;
            for ( nn = 0; nn < num_points; nn++ )
            {
              FT_Int  x = values[0];


              for ( mm = 1; mm < blend->num_designs; mm++ )
                x += FT_MulFix( *delta++, blend->weight_vector[mm] );

              *values++ = x;
            }
            /* note that `top' will be incremented later by calls to `pop' */
            break;
          }

        default:
        Unexpected_OtherSubr:
          FT_ERROR(( "Z1_Parse_CharStrings: invalid othersubr [%d %d]!\n",
                     top[0], top[1] ));
          goto Syntax_Error;
        }
        decoder->top = top;
      }
      else  /* general operator */
      {
        FT_Int  num_args = t1_args_count[op];


        if ( top - decoder->stack < num_args )
          goto Stack_Underflow;

        top -= num_args;

        switch ( op )
        {
        case op_endchar:
          FT_TRACE4(( " endchar" ));

          close_contour( builder );

          /* add current outline to the glyph slot */
          FT_GlyphLoader_Add( builder->loader );

          /* return now! */
          FT_TRACE4(( "\n\n" ));
          return T1_Err_Ok;

        case op_hsbw:
          FT_TRACE4(( " hsbw" ));

          builder->left_bearing.x += top[0];
          builder->advance.x       = top[1];
          builder->advance.y       = 0;

          builder->last.x = x = top[0];
          builder->last.y = y = 0;

          /* the `metrics_only' indicates that we only want to compute */
          /* the glyph's metrics (lsb + advance width), not load the   */
          /* rest of it; so exit immediately                           */
          if ( builder->metrics_only )
            return T1_Err_Ok;

          break;

        case op_seac:
          /* return immediately after the processing */
          return t1operator_seac( decoder, top[0], top[1],
                                           top[2], top[3], top[4] );

        case op_sbw:
          FT_TRACE4(( " sbw" ));

          builder->left_bearing.x += top[0];
          builder->left_bearing.y += top[1];
          builder->advance.x       = top[2];
          builder->advance.y       = top[3];

          builder->last.x = x = top[0];
          builder->last.y = y = top[1];

          /* the `metrics_only' indicates that we only want to compute */
          /* the glyph's metrics (lsb + advance width), not load the   */
          /* rest of it; so exit immediately                           */
          if ( builder->metrics_only )
            return T1_Err_Ok;

          break;

        case op_closepath:
          FT_TRACE4(( " closepath" ));

          close_contour( builder );
          builder->path_begun = 0;
          break;

        case op_hlineto:
          FT_TRACE4(( " hlineto" ));

          if ( start_point( builder, x, y ) )
            goto Memory_Error;

          x += top[0];
          goto Add_Line;

        case op_hmoveto:
          FT_TRACE4(( " hmoveto" ));

          x += top[0];
          break;

        case op_hvcurveto:
          FT_TRACE4(( " hvcurveto" ));

          if ( start_point( builder, x, y ) ||
               check_points( builder, 3 )   )
            goto Memory_Error;

          x += top[0];
          add_point( builder, x, y, 0 );
          x += top[1];
          y += top[2];
          add_point( builder, x, y, 0 );
          y += top[3];
          add_point( builder, x, y, 1 );
          break;

        case op_rlineto:
          FT_TRACE4(( " rlineto" ));

          if ( start_point( builder, x, y ) )
            goto Memory_Error;

          x += top[0];
          y += top[1];

        Add_Line:
          if ( add_point1( builder, x, y ) )
            goto Memory_Error;
          break;

        case op_rmoveto:
          FT_TRACE4(( " rmoveto" ));

          x += top[0];
          y += top[1];
          break;

        case op_rrcurveto:
          FT_TRACE4(( " rcurveto" ));

          if ( start_point( builder, x, y ) ||
               check_points( builder, 3 )   )
            goto Memory_Error;

          x += top[0];
          y += top[1];
          add_point( builder, x, y, 0 );

          x += top[2];
          y += top[3];
          add_point( builder, x, y, 0 );

          x += top[4];
          y += top[5];
          add_point( builder, x, y, 1 );
          break;

        case op_vhcurveto:
          FT_TRACE4(( " vhcurveto" ));

          if ( start_point( builder, x, y ) ||
               check_points( builder, 3 )   )
            goto Memory_Error;

          y += top[0];
          add_point( builder, x, y, 0 );
          x += top[1];
          y += top[2];
          add_point( builder, x, y, 0 );
          x += top[3];
          add_point( builder, x, y, 1 );
          break;

        case op_vlineto:
          FT_TRACE4(( " vlineto" ));

          if ( start_point( builder, x, y ) )
            goto Memory_Error;

          y += top[0];
          goto Add_Line;

        case op_vmoveto:
          FT_TRACE4(( " vmoveto" ));

          y += top[0];
          break;

        case op_div:
          FT_TRACE4(( " div" ));

          if ( top[1] )
          {
            *top = top[0] / top[1];
            ++top;
          }
          else
          {
            FT_ERROR(( "Z1_Parse_CharStrings: division by 0\n" ));
            goto Syntax_Error;
          }
          break;

        case op_callsubr:
          {
            FT_Int  index;


            FT_TRACE4(( " callsubr" ));

            index = top[0];
            if ( index < 0 || index >= num_subrs )
            {
              FT_ERROR(( "Z1_Parse_CharStrings: invalid subrs index\n" ));
              goto Syntax_Error;
            }

            if ( zone - decoder->zones >= T1_MAX_SUBRS_CALLS )
            {
              FT_ERROR(( "Z1_Parse_CharStrings: too many nested subrs\n" ));
              goto Syntax_Error;
            }

            zone->cursor = ip;  /* save current instruction pointer */

            zone++;
            zone->base   = subrs_base[index];
            zone->limit  = zone->base + subrs_len[index];
            zone->cursor = zone->base;

            if ( !zone->base )
            {
              FT_ERROR(( "Z1_Parse_CharStrings: invoking empty subrs!\n" ));
              goto Syntax_Error;
            }

            decoder->zone = zone;
            ip            = zone->base;
            limit         = zone->limit;
            break;
          }

        case op_pop:
          FT_TRACE4(( " pop" ));

          /* theorically, the arguments are already on the stack */
          top++;
          break;

        case op_return:
          FT_TRACE4(( " return" ));

          if ( zone <= decoder->zones )
          {
            FT_ERROR(( "Z1_Parse_CharStrings: unexpected return\n" ));
            goto Syntax_Error;
          }

          zone--;
          ip            = zone->cursor;
          limit         = zone->limit;
          decoder->zone = zone;
          break;

        case op_dotsection:
          FT_TRACE4(( " dotsection" ));

          break;

        case op_hstem:
          FT_TRACE4(( " hstem" ));

          break;

        case op_hstem3:
          FT_TRACE4(( " hstem3" ));

          break;

        case op_vstem:
          FT_TRACE4(( " vstem" ));

          break;

        case op_vstem3:
          FT_TRACE4(( " vstem3" ));

          break;

        case op_setcurrentpoint:
          FT_TRACE4(( " setcurrentpoint" ));

          FT_ERROR(( "Z1_Parse_CharStrings:" ));
          FT_ERROR(( " unexpected `setcurrentpoint'\n" ));
          goto Syntax_Error;

        default:
          FT_ERROR(( "Z1_Parse_CharStrings: unhandled opcode %d\n", op ));
          goto Syntax_Error;
        }

        decoder->top = top;

      } /* general operator processing */

    } /* while ip < limit */

    FT_TRACE4(( "..end..\n\n" ));
    return error;

  Syntax_Error:
    return T1_Err_Syntax_Error;

  Stack_Underflow:
    return T1_Err_Stack_Underflow;

  Memory_Error:
    return builder->error;
  }


  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/
  /**********                                                      *********/
  /**********            COMPUTE THE MAXIMUM ADVANCE WIDTH         *********/
  /**********                                                      *********/
  /**********    The following code is in charge of computing      *********/
  /**********    the maximum advance width of the font.  It        *********/
  /**********    quickly processes each glyph charstring to        *********/
  /**********    extract the value from either a `sbw' or `seac'   *********/
  /**********    operator.                                         *********/
  /**********                                                      *********/
  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/


  LOCAL_FUNC
  FT_Error  Z1_Compute_Max_Advance( T1_Face  face,
                                    FT_Int*  max_advance )
  {
    FT_Error    error;
    Z1_Decoder  decoder;
    FT_Int      glyph_index;
    T1_Font*    type1 = &face->type1;


    *max_advance = 0;

    /* Initialize load decoder */
    Z1_Init_Decoder( &decoder );
    Z1_Init_Builder( &decoder.builder, face, 0, 0 );

    decoder.blend                = face->blend;
    decoder.builder.metrics_only = 1;
    decoder.builder.load_points  = 0;

    /* for each glyph, parse the glyph charstring and extract */
    /* the advance width                                      */
    for ( glyph_index = 0; glyph_index < type1->num_glyphs; glyph_index++ )
    {
      /* now get load the unscaled outline */
      error = Z1_Parse_CharStrings( &decoder,
                                    type1->charstrings    [glyph_index],
                                    type1->charstrings_len[glyph_index],
                                    type1->num_subrs,
                                    type1->subrs,
                                    type1->subrs_len );
      /* ignore the error if one occured - skip to next glyph */
    }

    *max_advance = decoder.builder.advance.x;
    return T1_Err_Ok;
  }


  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/
  /**********                                                      *********/
  /**********               UNHINTED GLYPH LOADER                  *********/
  /**********                                                      *********/
  /**********    The following code is in charge of loading a      *********/
  /**********    single outline.  It completely ignores hinting    *********/
  /**********    and is used when FT_LOAD_NO_HINTING is set.       *********/
  /**********                                                      *********/
  /**********      The Type 1 hinter is located in `t1hint.c'      *********/
  /**********                                                      *********/
  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/


  LOCAL_FUNC
  FT_Error  Z1_Load_Glyph( Z1_GlyphSlot  glyph,
                           Z1_Size       size,
                           FT_Int        glyph_index,
                           FT_Int        load_flags )
  {
    FT_Error    error;
    Z1_Decoder  decoder;
    T1_Face     face = (T1_Face)glyph->root.face;
    FT_Bool     hinting;
    T1_Font*    type1 = &face->type1;


    if ( load_flags & FT_LOAD_NO_RECURSE )
      load_flags |= FT_LOAD_NO_SCALE | FT_LOAD_NO_HINTING;

    glyph->x_scale = size->root.metrics.x_scale;
    glyph->y_scale = size->root.metrics.y_scale;

    glyph->root.outline.n_points   = 0;
    glyph->root.outline.n_contours = 0;

    hinting = ( load_flags & FT_LOAD_NO_SCALE   ) == 0 &&
              ( load_flags & FT_LOAD_NO_HINTING ) == 0;

    glyph->root.format = ft_glyph_format_outline;

    Z1_Init_Decoder( &decoder );
    Z1_Init_Builder( &decoder.builder, face, size, glyph );

    decoder.blend              = ((T1_Face)glyph->root.face)->blend;
    decoder.builder.no_recurse = ( load_flags & FT_LOAD_NO_RECURSE ) != 0;

    /* now load the unscaled outline */
    error = Z1_Parse_CharStrings( &decoder,
                                  type1->charstrings    [glyph_index],
                                  type1->charstrings_len[glyph_index],
                                  type1->num_subrs,
                                  type1->subrs,
                                  type1->subrs_len );

    /* save new glyph tables */
    Z1_Done_Builder( &decoder.builder );

    /* now, set the metrics -- this is rather simple, as   */
    /* the left side bearing is the xMin, and the top side */
    /* bearing the yMax                                    */
    if ( !error )
    {
      glyph->root.outline.flags &= ft_outline_owner;
      glyph->root.outline.flags |= ft_outline_reverse_fill;
      
      /* for composite glyphs, return only left side bearing and */
      /* advance width                                           */
      if ( load_flags & FT_LOAD_NO_RECURSE )
      {
        glyph->root.metrics.horiBearingX = decoder.builder.left_bearing.x;
        glyph->root.metrics.horiAdvance  = decoder.builder.advance.x;
      }
      else
      {
        FT_BBox           cbox;
        FT_Glyph_Metrics* metrics = &glyph->root.metrics;


        /* copy the _unscaled_ advance width */
        metrics->horiAdvance = decoder.builder.advance.x;

        /* make up vertical metrics */
        metrics->vertBearingX = 0;
        metrics->vertBearingY = 0;
        metrics->vertAdvance  = 0;

        glyph->root.format = ft_glyph_format_outline;

        if ( size && size->root.metrics.y_ppem < 24 )
          glyph->root.outline.flags |= ft_outline_high_precision;

#if 0
        glyph->root.outline.second_pass    = TRUE;
        glyph->root.outline.high_precision = size->root.metrics.y_ppem < 24;
        glyph->root.outline.dropout_mode   = 2;
#endif /* 0 */

        if ( ( load_flags & FT_LOAD_NO_SCALE ) == 0 )
        {
          /* scale the outline and the metrics */
          FT_Int       n;
          FT_Outline*  cur = decoder.builder.base;
          FT_Vector*   vec = cur->points;
          FT_Fixed     x_scale = glyph->x_scale;
          FT_Fixed     y_scale = glyph->y_scale;


          /* First of all, scale the points */
          for ( n = cur->n_points; n > 0; n--, vec++ )
          {
            vec->x = FT_MulFix( vec->x, x_scale );
            vec->y = FT_MulFix( vec->y, y_scale );
          }

          FT_Outline_Get_CBox( &glyph->root.outline, &cbox );

          /* Then scale the metrics */
          metrics->horiAdvance  = FT_MulFix( metrics->horiAdvance,  x_scale );
          metrics->vertAdvance  = FT_MulFix( metrics->vertAdvance,  y_scale );

          metrics->vertBearingX = FT_MulFix( metrics->vertBearingX, x_scale );
          metrics->vertBearingY = FT_MulFix( metrics->vertBearingY, y_scale );
        }

        /* apply the font matrix */
        FT_Outline_Transform( &glyph->root.outline,
                              &face->type1.font_matrix );

        /* compute the other metrics */
        FT_Outline_Get_CBox( &glyph->root.outline, &cbox );

        /* grid fit the bounding box if necessary */
        if ( hinting )
        {
          cbox.xMin &= -64;
          cbox.yMin &= -64;
          cbox.xMax  = ( cbox.xMax+63 ) & -64;
          cbox.yMax  = ( cbox.yMax+63 ) & -64;
        }

        metrics->width  = cbox.xMax - cbox.xMin;
        metrics->height = cbox.yMax - cbox.yMin;

        metrics->horiBearingX = cbox.xMin;
        metrics->horiBearingY = cbox.yMax;
      }
    }
    return error;
  }


/* END */
kc3-lang/freetype/src/type1z/z1gload.c

Commit

kc3-lang/freetype /src/type1z/z1gload.c
