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      1 /***************************************************************************/
      2 /*                                                                         */
      3 /*  afloader.c                                                             */
      4 /*                                                                         */
      5 /*    Auto-fitter glyph loading routines (body).                           */
      6 /*                                                                         */
      7 /*  Copyright 2003-2009, 2011 by                                           */
      8 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
      9 /*                                                                         */
     10 /*  This file is part of the FreeType project, and may only be used,       */
     11 /*  modified, and distributed under the terms of the FreeType project      */
     12 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
     13 /*  this file you indicate that you have read the license and              */
     14 /*  understand and accept it fully.                                        */
     15 /*                                                                         */
     16 /***************************************************************************/
     17 
     18 
     19 #include "afloader.h"
     20 #include "afhints.h"
     21 #include "afglobal.h"
     22 #include "aferrors.h"
     23 
     24 
     25   /* Initialize glyph loader. */
     26 
     27   FT_LOCAL_DEF( FT_Error )
     28   af_loader_init( AF_Loader  loader,
     29                   FT_Memory  memory )
     30   {
     31     FT_ZERO( loader );
     32 
     33     af_glyph_hints_init( &loader->hints, memory );
     34 #ifdef FT_DEBUG_AUTOFIT
     35     _af_debug_hints = &loader->hints;
     36 #endif
     37     return FT_GlyphLoader_New( memory, &loader->gloader );
     38   }
     39 
     40 
     41   /* Reset glyph loader and compute globals if necessary. */
     42 
     43   FT_LOCAL_DEF( FT_Error )
     44   af_loader_reset( AF_Loader  loader,
     45                    FT_Face    face )
     46   {
     47     FT_Error  error = AF_Err_Ok;
     48 
     49 
     50     loader->face    = face;
     51     loader->globals = (AF_FaceGlobals)face->autohint.data;
     52 
     53     FT_GlyphLoader_Rewind( loader->gloader );
     54 
     55     if ( loader->globals == NULL )
     56     {
     57       error = af_face_globals_new( face, &loader->globals );
     58       if ( !error )
     59       {
     60         face->autohint.data =
     61           (FT_Pointer)loader->globals;
     62         face->autohint.finalizer =
     63           (FT_Generic_Finalizer)af_face_globals_free;
     64       }
     65     }
     66 
     67     return error;
     68   }
     69 
     70 
     71   /* Finalize glyph loader. */
     72 
     73   FT_LOCAL_DEF( void )
     74   af_loader_done( AF_Loader  loader )
     75   {
     76     af_glyph_hints_done( &loader->hints );
     77 
     78     loader->face    = NULL;
     79     loader->globals = NULL;
     80 
     81 #ifdef FT_DEBUG_AUTOFIT
     82     _af_debug_hints = NULL;
     83 #endif
     84     FT_GlyphLoader_Done( loader->gloader );
     85     loader->gloader = NULL;
     86   }
     87 
     88 
     89   /* Load a single glyph component.  This routine calls itself */
     90   /* recursively, if necessary, and does the main work of      */
     91   /* `af_loader_load_glyph.'                                   */
     92 
     93   static FT_Error
     94   af_loader_load_g( AF_Loader  loader,
     95                     AF_Scaler  scaler,
     96                     FT_UInt    glyph_index,
     97                     FT_Int32   load_flags,
     98                     FT_UInt    depth )
     99   {
    100     FT_Error          error;
    101     FT_Face           face     = loader->face;
    102     FT_GlyphLoader    gloader  = loader->gloader;
    103     AF_ScriptMetrics  metrics  = loader->metrics;
    104     AF_GlyphHints     hints    = &loader->hints;
    105     FT_GlyphSlot      slot     = face->glyph;
    106     FT_Slot_Internal  internal = slot->internal;
    107 
    108 
    109     error = FT_Load_Glyph( face, glyph_index, load_flags );
    110     if ( error )
    111       goto Exit;
    112 
    113     loader->transformed = internal->glyph_transformed;
    114     if ( loader->transformed )
    115     {
    116       FT_Matrix  inverse;
    117 
    118 
    119       loader->trans_matrix = internal->glyph_matrix;
    120       loader->trans_delta  = internal->glyph_delta;
    121 
    122       inverse = loader->trans_matrix;
    123       FT_Matrix_Invert( &inverse );
    124       FT_Vector_Transform( &loader->trans_delta, &inverse );
    125     }
    126 
    127     /* set linear metrics */
    128     slot->linearHoriAdvance = slot->metrics.horiAdvance;
    129     slot->linearVertAdvance = slot->metrics.vertAdvance;
    130 
    131     switch ( slot->format )
    132     {
    133     case FT_GLYPH_FORMAT_OUTLINE:
    134       /* translate the loaded glyph when an internal transform is needed */
    135       if ( loader->transformed )
    136         FT_Outline_Translate( &slot->outline,
    137                               loader->trans_delta.x,
    138                               loader->trans_delta.y );
    139 
    140       /* copy the outline points in the loader's current               */
    141       /* extra points which is used to keep original glyph coordinates */
    142       error = FT_GLYPHLOADER_CHECK_POINTS( gloader,
    143                                            slot->outline.n_points + 4,
    144                                            slot->outline.n_contours );
    145       if ( error )
    146         goto Exit;
    147 
    148       FT_ARRAY_COPY( gloader->current.outline.points,
    149                      slot->outline.points,
    150                      slot->outline.n_points );
    151 
    152       FT_ARRAY_COPY( gloader->current.outline.contours,
    153                      slot->outline.contours,
    154                      slot->outline.n_contours );
    155 
    156       FT_ARRAY_COPY( gloader->current.outline.tags,
    157                      slot->outline.tags,
    158                      slot->outline.n_points );
    159 
    160       gloader->current.outline.n_points   = slot->outline.n_points;
    161       gloader->current.outline.n_contours = slot->outline.n_contours;
    162 
    163       /* compute original horizontal phantom points (and ignore */
    164       /* vertical ones)                                         */
    165       loader->pp1.x = hints->x_delta;
    166       loader->pp1.y = hints->y_delta;
    167       loader->pp2.x = FT_MulFix( slot->metrics.horiAdvance,
    168                                  hints->x_scale ) + hints->x_delta;
    169       loader->pp2.y = hints->y_delta;
    170 
    171       /* be sure to check for spacing glyphs */
    172       if ( slot->outline.n_points == 0 )
    173         goto Hint_Metrics;
    174 
    175       /* now load the slot image into the auto-outline and run the */
    176       /* automatic hinting process                                 */
    177       if ( metrics->clazz->script_hints_apply )
    178         metrics->clazz->script_hints_apply( hints,
    179                                             &gloader->current.outline,
    180                                             metrics );
    181 
    182       /* we now need to adjust the metrics according to the change in */
    183       /* width/positioning that occurred during the hinting process   */
    184       if ( scaler->render_mode != FT_RENDER_MODE_LIGHT )
    185       {
    186         FT_Pos        old_rsb, old_lsb, new_lsb;
    187         FT_Pos        pp1x_uh, pp2x_uh;
    188         AF_AxisHints  axis  = &hints->axis[AF_DIMENSION_HORZ];
    189         AF_Edge       edge1 = axis->edges;         /* leftmost edge  */
    190         AF_Edge       edge2 = edge1 +
    191                               axis->num_edges - 1; /* rightmost edge */
    192 
    193 
    194         if ( axis->num_edges > 1 && AF_HINTS_DO_ADVANCE( hints ) )
    195         {
    196           old_rsb = loader->pp2.x - edge2->opos;
    197           old_lsb = edge1->opos;
    198           new_lsb = edge1->pos;
    199 
    200           /* remember unhinted values to later account */
    201           /* for rounding errors                       */
    202 
    203           pp1x_uh = new_lsb    - old_lsb;
    204           pp2x_uh = edge2->pos + old_rsb;
    205 
    206           /* prefer too much space over too little space */
    207           /* for very small sizes                        */
    208 
    209           if ( old_lsb < 24 )
    210             pp1x_uh -= 8;
    211 
    212           if ( old_rsb < 24 )
    213             pp2x_uh += 8;
    214 
    215           loader->pp1.x = FT_PIX_ROUND( pp1x_uh );
    216           loader->pp2.x = FT_PIX_ROUND( pp2x_uh );
    217 
    218           if ( loader->pp1.x >= new_lsb && old_lsb > 0 )
    219             loader->pp1.x -= 64;
    220 
    221           if ( loader->pp2.x <= edge2->pos && old_rsb > 0 )
    222             loader->pp2.x += 64;
    223 
    224           slot->lsb_delta = loader->pp1.x - pp1x_uh;
    225           slot->rsb_delta = loader->pp2.x - pp2x_uh;
    226         }
    227         else
    228         {
    229           FT_Pos  pp1x = loader->pp1.x;
    230           FT_Pos  pp2x = loader->pp2.x;
    231 
    232 
    233           loader->pp1.x = FT_PIX_ROUND( pp1x );
    234           loader->pp2.x = FT_PIX_ROUND( pp2x );
    235 
    236           slot->lsb_delta = loader->pp1.x - pp1x;
    237           slot->rsb_delta = loader->pp2.x - pp2x;
    238         }
    239       }
    240       else
    241       {
    242         FT_Pos  pp1x = loader->pp1.x;
    243         FT_Pos  pp2x = loader->pp2.x;
    244 
    245 
    246         loader->pp1.x = FT_PIX_ROUND( pp1x + hints->xmin_delta );
    247         loader->pp2.x = FT_PIX_ROUND( pp2x + hints->xmax_delta );
    248 
    249         slot->lsb_delta = loader->pp1.x - pp1x;
    250         slot->rsb_delta = loader->pp2.x - pp2x;
    251       }
    252 
    253       /* good, we simply add the glyph to our loader's base */
    254       FT_GlyphLoader_Add( gloader );
    255       break;
    256 
    257     case FT_GLYPH_FORMAT_COMPOSITE:
    258       {
    259         FT_UInt      nn, num_subglyphs = slot->num_subglyphs;
    260         FT_UInt      num_base_subgs, start_point;
    261         FT_SubGlyph  subglyph;
    262 
    263 
    264         start_point = gloader->base.outline.n_points;
    265 
    266         /* first of all, copy the subglyph descriptors in the glyph loader */
    267         error = FT_GlyphLoader_CheckSubGlyphs( gloader, num_subglyphs );
    268         if ( error )
    269           goto Exit;
    270 
    271         FT_ARRAY_COPY( gloader->current.subglyphs,
    272                        slot->subglyphs,
    273                        num_subglyphs );
    274 
    275         gloader->current.num_subglyphs = num_subglyphs;
    276         num_base_subgs                 = gloader->base.num_subglyphs;
    277 
    278         /* now read each subglyph independently */
    279         for ( nn = 0; nn < num_subglyphs; nn++ )
    280         {
    281           FT_Vector  pp1, pp2;
    282           FT_Pos     x, y;
    283           FT_UInt    num_points, num_new_points, num_base_points;
    284 
    285 
    286           /* gloader.current.subglyphs can change during glyph loading due */
    287           /* to re-allocation -- we must recompute the current subglyph on */
    288           /* each iteration                                                */
    289           subglyph = gloader->base.subglyphs + num_base_subgs + nn;
    290 
    291           pp1 = loader->pp1;
    292           pp2 = loader->pp2;
    293 
    294           num_base_points = gloader->base.outline.n_points;
    295 
    296           error = af_loader_load_g( loader, scaler, subglyph->index,
    297                                     load_flags, depth + 1 );
    298           if ( error )
    299             goto Exit;
    300 
    301           /* recompute subglyph pointer */
    302           subglyph = gloader->base.subglyphs + num_base_subgs + nn;
    303 
    304           if ( subglyph->flags & FT_SUBGLYPH_FLAG_USE_MY_METRICS )
    305           {
    306             pp1 = loader->pp1;
    307             pp2 = loader->pp2;
    308           }
    309           else
    310           {
    311             loader->pp1 = pp1;
    312             loader->pp2 = pp2;
    313           }
    314 
    315           num_points     = gloader->base.outline.n_points;
    316           num_new_points = num_points - num_base_points;
    317 
    318           /* now perform the transformation required for this subglyph */
    319 
    320           if ( subglyph->flags & ( FT_SUBGLYPH_FLAG_SCALE    |
    321                                    FT_SUBGLYPH_FLAG_XY_SCALE |
    322                                    FT_SUBGLYPH_FLAG_2X2      ) )
    323           {
    324             FT_Vector*  cur   = gloader->base.outline.points +
    325                                 num_base_points;
    326             FT_Vector*  limit = cur + num_new_points;
    327 
    328 
    329             for ( ; cur < limit; cur++ )
    330               FT_Vector_Transform( cur, &subglyph->transform );
    331           }
    332 
    333           /* apply offset */
    334 
    335           if ( !( subglyph->flags & FT_SUBGLYPH_FLAG_ARGS_ARE_XY_VALUES ) )
    336           {
    337             FT_Int      k = subglyph->arg1;
    338             FT_UInt     l = subglyph->arg2;
    339             FT_Vector*  p1;
    340             FT_Vector*  p2;
    341 
    342 
    343             if ( start_point + k >= num_base_points         ||
    344                                l >= (FT_UInt)num_new_points )
    345             {
    346               error = AF_Err_Invalid_Composite;
    347               goto Exit;
    348             }
    349 
    350             l += num_base_points;
    351 
    352             /* for now, only use the current point coordinates;    */
    353             /* we may consider another approach in the near future */
    354             p1 = gloader->base.outline.points + start_point + k;
    355             p2 = gloader->base.outline.points + start_point + l;
    356 
    357             x = p1->x - p2->x;
    358             y = p1->y - p2->y;
    359           }
    360           else
    361           {
    362             x = FT_MulFix( subglyph->arg1, hints->x_scale ) + hints->x_delta;
    363             y = FT_MulFix( subglyph->arg2, hints->y_scale ) + hints->y_delta;
    364 
    365             x = FT_PIX_ROUND( x );
    366             y = FT_PIX_ROUND( y );
    367           }
    368 
    369           {
    370             FT_Outline  dummy = gloader->base.outline;
    371 
    372 
    373             dummy.points  += num_base_points;
    374             dummy.n_points = (short)num_new_points;
    375 
    376             FT_Outline_Translate( &dummy, x, y );
    377           }
    378         }
    379       }
    380       break;
    381 
    382     default:
    383       /* we don't support other formats (yet?) */
    384       error = AF_Err_Unimplemented_Feature;
    385     }
    386 
    387   Hint_Metrics:
    388     if ( depth == 0 )
    389     {
    390       FT_BBox    bbox;
    391       FT_Vector  vvector;
    392 
    393 
    394       vvector.x = slot->metrics.vertBearingX - slot->metrics.horiBearingX;
    395       vvector.y = slot->metrics.vertBearingY - slot->metrics.horiBearingY;
    396       vvector.x = FT_MulFix( vvector.x, metrics->scaler.x_scale );
    397       vvector.y = FT_MulFix( vvector.y, metrics->scaler.y_scale );
    398 
    399       /* transform the hinted outline if needed */
    400       if ( loader->transformed )
    401       {
    402         FT_Outline_Transform( &gloader->base.outline, &loader->trans_matrix );
    403         FT_Vector_Transform( &vvector, &loader->trans_matrix );
    404       }
    405 #if 1
    406       /* we must translate our final outline by -pp1.x and compute */
    407       /* the new metrics                                           */
    408       if ( loader->pp1.x )
    409         FT_Outline_Translate( &gloader->base.outline, -loader->pp1.x, 0 );
    410 #endif
    411       FT_Outline_Get_CBox( &gloader->base.outline, &bbox );
    412 
    413       bbox.xMin = FT_PIX_FLOOR( bbox.xMin );
    414       bbox.yMin = FT_PIX_FLOOR( bbox.yMin );
    415       bbox.xMax = FT_PIX_CEIL(  bbox.xMax );
    416       bbox.yMax = FT_PIX_CEIL(  bbox.yMax );
    417 
    418       slot->metrics.width        = bbox.xMax - bbox.xMin;
    419       slot->metrics.height       = bbox.yMax - bbox.yMin;
    420       slot->metrics.horiBearingX = bbox.xMin;
    421       slot->metrics.horiBearingY = bbox.yMax;
    422 
    423       slot->metrics.vertBearingX = FT_PIX_FLOOR( bbox.xMin + vvector.x );
    424       slot->metrics.vertBearingY = FT_PIX_FLOOR( bbox.yMax + vvector.y );
    425 
    426       /* for mono-width fonts (like Andale, Courier, etc.) we need */
    427       /* to keep the original rounded advance width; ditto for     */
    428       /* digits if all have the same advance width                 */
    429 #if 0
    430       if ( !FT_IS_FIXED_WIDTH( slot->face ) )
    431         slot->metrics.horiAdvance = loader->pp2.x - loader->pp1.x;
    432       else
    433         slot->metrics.horiAdvance = FT_MulFix( slot->metrics.horiAdvance,
    434                                                x_scale );
    435 #else
    436       if ( FT_IS_FIXED_WIDTH( slot->face )                              ||
    437            ( af_face_globals_is_digit( loader->globals, glyph_index ) &&
    438              metrics->digits_have_same_width                          ) )
    439       {
    440         slot->metrics.horiAdvance = FT_MulFix( slot->metrics.horiAdvance,
    441                                                metrics->scaler.x_scale );
    442 
    443         /* Set delta values to 0.  Otherwise code that uses them is */
    444         /* going to ruin the fixed advance width.                   */
    445         slot->lsb_delta = 0;
    446         slot->rsb_delta = 0;
    447       }
    448       else
    449       {
    450         /* non-spacing glyphs must stay as-is */
    451         if ( slot->metrics.horiAdvance )
    452           slot->metrics.horiAdvance = loader->pp2.x - loader->pp1.x;
    453       }
    454 #endif
    455 
    456       slot->metrics.vertAdvance = FT_MulFix( slot->metrics.vertAdvance,
    457                                              metrics->scaler.y_scale );
    458 
    459       slot->metrics.horiAdvance = FT_PIX_ROUND( slot->metrics.horiAdvance );
    460       slot->metrics.vertAdvance = FT_PIX_ROUND( slot->metrics.vertAdvance );
    461 
    462       /* now copy outline into glyph slot */
    463       FT_GlyphLoader_Rewind( internal->loader );
    464       error = FT_GlyphLoader_CopyPoints( internal->loader, gloader );
    465       if ( error )
    466         goto Exit;
    467 
    468       slot->outline = internal->loader->base.outline;
    469       slot->format  = FT_GLYPH_FORMAT_OUTLINE;
    470     }
    471 
    472   Exit:
    473     return error;
    474   }
    475 
    476 
    477   /* Load a glyph. */
    478 
    479   FT_LOCAL_DEF( FT_Error )
    480   af_loader_load_glyph( AF_Loader  loader,
    481                         FT_Face    face,
    482                         FT_UInt    gindex,
    483                         FT_UInt32  load_flags )
    484   {
    485     FT_Error      error;
    486     FT_Size       size = face->size;
    487     AF_ScalerRec  scaler;
    488 
    489 
    490     if ( !size )
    491       return AF_Err_Invalid_Argument;
    492 
    493     FT_ZERO( &scaler );
    494 
    495     scaler.face    = face;
    496     scaler.x_scale = size->metrics.x_scale;
    497     scaler.x_delta = 0;  /* XXX: TODO: add support for sub-pixel hinting */
    498     scaler.y_scale = size->metrics.y_scale;
    499     scaler.y_delta = 0;  /* XXX: TODO: add support for sub-pixel hinting */
    500 
    501     scaler.render_mode = FT_LOAD_TARGET_MODE( load_flags );
    502     scaler.flags       = 0;  /* XXX: fix this */
    503 
    504     error = af_loader_reset( loader, face );
    505     if ( !error )
    506     {
    507       AF_ScriptMetrics  metrics;
    508       FT_UInt           options = 0;
    509 
    510 
    511 #ifdef FT_OPTION_AUTOFIT2
    512       /* XXX: undocumented hook to activate the latin2 hinter */
    513       if ( load_flags & ( 1UL << 20 ) )
    514         options = 2;
    515 #endif
    516 
    517       error = af_face_globals_get_metrics( loader->globals, gindex,
    518                                            options, &metrics );
    519       if ( !error )
    520       {
    521         loader->metrics = metrics;
    522 
    523         if ( metrics->clazz->script_metrics_scale )
    524           metrics->clazz->script_metrics_scale( metrics, &scaler );
    525         else
    526           metrics->scaler = scaler;
    527 
    528         load_flags |=  FT_LOAD_NO_SCALE | FT_LOAD_IGNORE_TRANSFORM;
    529         load_flags &= ~FT_LOAD_RENDER;
    530 
    531         if ( metrics->clazz->script_hints_init )
    532         {
    533           error = metrics->clazz->script_hints_init( &loader->hints,
    534                                                      metrics );
    535           if ( error )
    536             goto Exit;
    537         }
    538 
    539         error = af_loader_load_g( loader, &scaler, gindex, load_flags, 0 );
    540       }
    541     }
    542   Exit:
    543     return error;
    544   }
    545 
    546 
    547 /* END */
    548