ttgload.c

神龙卡开发原代码

        /* exit states: Load_Glyph                                  */
        /*                                                          */

      case Load_Composite:

        /* create a new element on the stack */
        load_top++;

        if ( load_top > face->maxComponents )
        {
          error = TT_Err_Invalid_Composite;
          goto Fail;
        }

        subglyph2 = exec->loadStack + load_top;

        Init_Glyph_Component( subglyph2, subglyph, NULL );
        subglyph2->is_hinted = subglyph->is_hinted;

        /* now read composite header */

        if ( ACCESS_Frame( 4L ) )
          goto Fail_File;

        subglyph->element_flag = new_flags = GET_UShort();

        subglyph2->index = GET_UShort();

        FORGET_Frame();

        k = 1 + 1;

        if ( new_flags & ARGS_ARE_WORDS )
          k *= 2;

        if ( new_flags & WE_HAVE_A_SCALE )
          k += 2;

        else if ( new_flags & WE_HAVE_AN_XY_SCALE )
          k += 4;

        else if ( new_flags & WE_HAVE_A_2X2 )
          k += 8;

        if ( ACCESS_Frame( k ) )
          goto Fail_File;

        if ( new_flags & ARGS_ARE_WORDS )
        {
          k = GET_Short();
          l = GET_Short();
        }
        else
        {
          k = GET_Char();
          l = GET_Char();
        }

        subglyph->arg1 = k;
        subglyph->arg2 = l;

        if ( new_flags & ARGS_ARE_XY_VALUES )
        {
          subglyph->transform.ox = k;
          subglyph->transform.oy = l;
        }

        xx = 1L << 16;
        xy = 0;
        yx = 0;
        yy = 1L << 16;

        if ( new_flags & WE_HAVE_A_SCALE )
        {
          xx = (Fixed)GET_Short() << 2;
          yy = xx;
          subglyph2->is_scaled = TRUE;
        }
        else if ( new_flags & WE_HAVE_AN_XY_SCALE )
        {
          xx = (Fixed)GET_Short() << 2;
          yy = (Fixed)GET_Short() << 2;
          subglyph2->is_scaled = TRUE;
        }
        else if ( new_flags & WE_HAVE_A_2X2 )
        {
          xx = (Fixed)GET_Short() << 2;
          xy = (Fixed)GET_Short() << 2;
          yx = (Fixed)GET_Short() << 2;
          yy = (Fixed)GET_Short() << 2;
          subglyph2->is_scaled = TRUE;
        }

        FORGET_Frame();

        subglyph->transform.xx = xx;
        subglyph->transform.xy = xy;
        subglyph->transform.yx = yx;
        subglyph->transform.yy = yy;

        k = TT_MulFix( xx, yy ) -  TT_MulFix( xy, yx );

        /* disable hinting in case of scaling/slanting */
        if ( ABS( k ) != (1L << 16) )
          subglyph2->is_hinted = FALSE;

        subglyph->file_offset = FILE_Pos();

        phase = Load_Glyph;

        break;


        /************************************************************/
        /*                                                          */
        /* Load_End state                                           */
        /*                                                          */
        /*   after loading a glyph, apply transformation and offset */
        /*   where necessary, pops element and continue or          */
        /*   stop process.                                          */
        /*                                                          */
        /* exit states : Load_Composite and Load_Exit               */
        /*                                                          */

      case Load_End:
        if ( load_top > 0 )
        {
          subglyph2 = subglyph;

          load_top--;
          subglyph = exec->loadStack + load_top;

          /* check advance width and left side bearing */

          if ( !subglyph->preserve_pps &&
               subglyph->element_flag & USE_MY_METRICS )
          {
            subglyph->metrics.horiBearingX = subglyph2->metrics.horiBearingX;
            subglyph->metrics.horiAdvance  = subglyph2->metrics.horiAdvance;

            subglyph->pp1 = subglyph2->pp1;
            subglyph->pp2 = subglyph2->pp2;

            subglyph->preserve_pps = TRUE;
          }

          /* apply scale */

          if ( subglyph2->is_scaled )
          {
            TT_Vector*  cur = subglyph2->zone.cur;
            TT_Vector*  org = subglyph2->zone.org;

            for ( u = 0; u < num_points; u++ )
            {
              nx = TT_MulFix( cur->x, subglyph->transform.xx ) +
                   TT_MulFix( cur->y, subglyph->transform.yx );

              ny = TT_MulFix( cur->x, subglyph->transform.xy ) +
                   TT_MulFix( cur->y, subglyph->transform.yy );

              cur->x = nx;
              cur->y = ny;

              nx = TT_MulFix( org->x, subglyph->transform.xx ) +
                   TT_MulFix( org->y, subglyph->transform.yx );

              ny = TT_MulFix( org->x, subglyph->transform.xy ) +
                   TT_MulFix( org->y, subglyph->transform.yy );

              org->x = nx;
              org->y = ny;

              cur++;
              org++;
            }
          }

          /* adjust counts */

          num_elem_points = subglyph->zone.n_points;

          for ( k = 0; k < num_contours; k++ )
            subglyph2->zone.contours[k] += num_elem_points;

          subglyph->zone.n_points   += num_points;
          subglyph->zone.n_contours += num_contours;

          left_points   -= num_points;
          left_contours -= num_contours;

          if ( !(subglyph->element_flag & ARGS_ARE_XY_VALUES) )
          {
            /* move second glyph according to control points */
            /* the attach points are relative to the specific component */

            u = (UShort)subglyph->arg1;
            v = (UShort)subglyph->arg2;

            if ( u >= num_elem_points ||
                 v >= num_points )
            {
              error = TT_Err_Invalid_Composite;
              goto Fail;
            }

            /* adjust count */
            v += num_elem_points;

            x = subglyph->zone.cur[u].x - subglyph->zone.cur[v].x;
            y = subglyph->zone.cur[u].y - subglyph->zone.cur[v].y;
          }
          else
          {
            /* apply offset */

            x = subglyph->transform.ox;
            y = subglyph->transform.oy;

            if ( load_flags & TTLOAD_SCALE_GLYPH )
            {
              x = Scale_X( &exec->metrics, x );
              y = Scale_Y( &exec->metrics, y );

              if ( subglyph->element_flag & ROUND_XY_TO_GRID )
              {
                x = (x+32) & -64;
                y = (y+32) & -64;
              }
            }
          }

          translate_array( num_points, subglyph2->zone.cur, x, y );

          cur_to_org( num_points, &subglyph2->zone );

          num_points   = subglyph->zone.n_points;
          num_contours = subglyph->zone.n_contours;

          /* check for last component */

          if ( FILE_Seek( subglyph->file_offset ) )
            goto Fail_File;

          if ( subglyph->element_flag & MORE_COMPONENTS )
            phase = Load_Composite;
          else
          {
            error = Load_Composite_End( num_points,
                                        num_contours,
                                        exec,
                                        subglyph,
                                        load_flags,
                                        stream );
            if ( error )
              goto Fail;

            phase = Load_End;
          }
        }
        else
          phase = Load_Exit;

        break;


      case Load_Exit:
        break;
      }
    }

    /* finally, copy the points arrays to the glyph object */

    exec->pts = base_pts;

    for ( u = 0; u < num_points + 2; u++ )
    {
      glyph->outline.points[u] = exec->pts.cur[u];
      glyph->outline.flags [u] = exec->pts.touch[u];
    }

    for ( k = 0; k < num_contours; k++ )
      glyph->outline.contours[k] = exec->pts.contours[k];

    glyph->outline.n_points    = num_points;
    glyph->outline.n_contours  = num_contours;
    glyph->outline.second_pass = TRUE;

    /* translate array so that (0,0) is the glyph's origin */
    translate_array( num_points + 2,
                     glyph->outline.points,
                     -subglyph->pp1.x,
                     0 );

    TT_Get_Outline_BBox( &glyph->outline, &glyph->metrics.bbox );

    if ( subglyph->is_hinted )
    {
      /* grid-fit the bounding box */
      glyph->metrics.bbox.xMin &= -64;
      glyph->metrics.bbox.yMin &= -64;
      glyph->metrics.bbox.xMax  = (glyph->metrics.bbox.xMax+63) & -64;
      glyph->metrics.bbox.yMax  = (glyph->metrics.bbox.yMax+63) & -64;
    }

    /* get the device-independent scaled horizontal metrics */
    /* take care of fixed-pitch fonts...                    */
    {
      TT_Pos  left_bearing;
      TT_Pos  advance;


      left_bearing = subglyph->metrics.horiBearingX;
      advance      = subglyph->metrics.horiAdvance;

      if ( face->postscript.isFixedPitch )
        advance = face->horizontalHeader.advance_Width_Max;

      if ( load_flags & TTLOAD_SCALE_GLYPH )
      {
        left_bearing = Scale_X( &exec->metrics, left_bearing );
        advance      = Scale_X( &exec->metrics, advance      );
      }

      glyph->metrics.linearHoriBearingX = left_bearing;
      glyph->metrics.linearHoriAdvance  = advance;
    }

    glyph->metrics.horiBearingX = glyph->metrics.bbox.xMin;
    glyph->metrics.horiBearingY = glyph->metrics.bbox.yMax;
    glyph->metrics.horiAdvance  = subglyph->pp2.x - subglyph->pp1.x;

    /* Now take care of vertical metrics.  In the case where there is    */
    /* no vertical information within the font (relatively common), make */
    /* up some metrics `by hand' ...                                     */

    {
      Short   top_bearing;    /* vertical top side bearing (EM units) */
      UShort  advance_height; /* vertical advance height (EM units)   */

      TT_Pos  left;     /* scaled vertical left side bearing          */
      TT_Pos  Top;      /* scaled original vertical top side bearing  */
      TT_Pos  top;      /* scaled vertical top side bearing           */
      TT_Pos  advance;  /* scaled vertical advance height             */


      /* Get the unscaled `tsb' and `ah' values */
      if ( face->verticalInfo                          &&
           face->verticalHeader.number_Of_VMetrics > 0 )
      {
        /* Don't assume that both the vertical header and vertical */
        /* metrics are present in the same font :-)                */

        TT_Get_Metrics( (TT_Horizontal_Header*)&face->verticalHeader,
                        glyph_index,
                        &top_bearing,
                        &advance_height );
      }
      else
      {
        /* Make up the distances from the horizontal header..     */

        /* NOTE: The OS/2 values are the only `portable' ones,    */
        /*       which is why we use them...                      */
        /*                                                        */
        /* NOTE2: The sTypoDescender is negative, which is why    */
        /*        we compute the baseline-to-baseline distance    */
        /*        here with :                                     */
        /*             ascender - descender + linegap             */
        /*                                                        */
        top_bearing    = (Short) (face->os2.sTypoLineGap / 2);
        advance_height = (UShort)(face->os2.sTypoAscender -
                                  face->os2.sTypoDescender +
                                  face->os2.sTypoLineGap);
      }

      /* We must adjust the top_bearing value from the bounding box given
         in the glyph header to te bounding box calculated with
         TT_Get_Outline_BBox()                                            */

      /* scale the metrics */
      if ( load_flags & TTLOAD_SCALE_GLYPH )
      {
        Top     = Scale_Y( &exec->metrics, top_bearing );
        top     = Scale_Y( &exec->metrics,
                           top_bearing + subglyph->metrics.bbox.yMax ) -
                    glyph->metrics.bbox.yMax;
        advance = Scale_Y( &exec->metrics, advance_height );
      }
      else
      {
        Top     = top_bearing;
        top     = top_bearing + subglyph->metrics.bbox.yMax -
                    glyph->metrics.bbox.yMax;
        advance = advance_height;
      }

      glyph->metrics.linearVertBearingY = Top;
      glyph->metrics.linearVertAdvance  = advance;

      /* XXX : for now, we have no better algo for the lsb, but it should */
      /*       work ok..                                                  */
      /*                                                                  */
      left = ( glyph->metrics.bbox.xMin - glyph->metrics.bbox.xMax ) / 2;

      /* grid-fit them if necessary */
      if ( subglyph->is_hinted )
      {
        left   &= -64;
        top     = (top + 63) & -64;
        advance = (advance + 32) & -64;
      }

      glyph->metrics.vertBearingX = left;
      glyph->metrics.vertBearingY = top;
      glyph->metrics.vertAdvance  = advance;
    }

    /* Adjust advance width to the value contained in the hdmx table. */
    if ( !exec->face->postscript.isFixedPitch && instance &&
         subglyph->is_hinted )
    {
      widths = Get_Advance_Widths( exec->face,
                                   exec->instance->metrics.x_ppem );
      if ( widths )
        glyph->metrics.horiAdvance = widths[glyph_index] << 6;
    }

    glyph->outline.dropout_mode = (Char)exec->GS.scan_type;

    error = TT_Err_Ok;

  Fail_File:
  Fail:
    DONE_Stream( stream );

  Fin:

    /* reset the execution context */
    exec->pts = base_pts;

    if ( !instance || !instance->debug )
      Done_Context( exec );

    return error;
  }


/* END */