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      1 /***************************************************************************/
      2 /*                                                                         */
      3 /*  ftsmooth.c                                                             */
      4 /*                                                                         */
      5 /*    Anti-aliasing renderer interface (body).                             */
      6 /*                                                                         */
      7 /*  Copyright 2000-2006, 2009-2012 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 <ft2build.h>
     20 #include FT_INTERNAL_DEBUG_H
     21 #include FT_INTERNAL_OBJECTS_H
     22 #include FT_OUTLINE_H
     23 #include "ftsmooth.h"
     24 #include "ftgrays.h"
     25 #include "ftspic.h"
     26 
     27 #include "ftsmerrs.h"
     28 
     29 
     30   /* initialize renderer -- init its raster */
     31   static FT_Error
     32   ft_smooth_init( FT_Renderer  render )
     33   {
     34     FT_Library  library = FT_MODULE_LIBRARY( render );
     35 
     36 
     37     render->clazz->raster_class->raster_reset( render->raster,
     38                                                library->raster_pool,
     39                                                library->raster_pool_size );
     40 
     41     return 0;
     42   }
     43 
     44 
     45   /* sets render-specific mode */
     46   static FT_Error
     47   ft_smooth_set_mode( FT_Renderer  render,
     48                       FT_ULong     mode_tag,
     49                       FT_Pointer   data )
     50   {
     51     /* we simply pass it to the raster */
     52     return render->clazz->raster_class->raster_set_mode( render->raster,
     53                                                          mode_tag,
     54                                                          data );
     55   }
     56 
     57   /* transform a given glyph image */
     58   static FT_Error
     59   ft_smooth_transform( FT_Renderer       render,
     60                        FT_GlyphSlot      slot,
     61                        const FT_Matrix*  matrix,
     62                        const FT_Vector*  delta )
     63   {
     64     FT_Error  error = Smooth_Err_Ok;
     65 
     66 
     67     if ( slot->format != render->glyph_format )
     68     {
     69       error = Smooth_Err_Invalid_Argument;
     70       goto Exit;
     71     }
     72 
     73     if ( matrix )
     74       FT_Outline_Transform( &slot->outline, matrix );
     75 
     76     if ( delta )
     77       FT_Outline_Translate( &slot->outline, delta->x, delta->y );
     78 
     79   Exit:
     80     return error;
     81   }
     82 
     83 
     84   /* return the glyph's control box */
     85   static void
     86   ft_smooth_get_cbox( FT_Renderer   render,
     87                       FT_GlyphSlot  slot,
     88                       FT_BBox*      cbox )
     89   {
     90     FT_MEM_ZERO( cbox, sizeof ( *cbox ) );
     91 
     92     if ( slot->format == render->glyph_format )
     93       FT_Outline_Get_CBox( &slot->outline, cbox );
     94   }
     95 
     96 
     97   /* convert a slot's glyph image into a bitmap */
     98   static FT_Error
     99   ft_smooth_render_generic( FT_Renderer       render,
    100                             FT_GlyphSlot      slot,
    101                             FT_Render_Mode    mode,
    102                             const FT_Vector*  origin,
    103                             FT_Render_Mode    required_mode )
    104   {
    105     FT_Error     error;
    106     FT_Outline*  outline = NULL;
    107     FT_BBox      cbox;
    108     FT_Pos       width, height, pitch;
    109 #ifndef FT_CONFIG_OPTION_SUBPIXEL_RENDERING
    110     FT_Pos       height_org, width_org;
    111 #endif
    112     FT_Bitmap*   bitmap;
    113     FT_Memory    memory;
    114     FT_Int       hmul = mode == FT_RENDER_MODE_LCD;
    115     FT_Int       vmul = mode == FT_RENDER_MODE_LCD_V;
    116     FT_Pos       x_shift, y_shift, x_left, y_top;
    117 
    118     FT_Raster_Params  params;
    119 
    120 
    121     /* check glyph image format */
    122     if ( slot->format != render->glyph_format )
    123     {
    124       error = Smooth_Err_Invalid_Argument;
    125       goto Exit;
    126     }
    127 
    128     /* check mode */
    129     if ( mode != required_mode )
    130       return Smooth_Err_Cannot_Render_Glyph;
    131 
    132     outline = &slot->outline;
    133 
    134     /* translate the outline to the new origin if needed */
    135     if ( origin )
    136       FT_Outline_Translate( outline, origin->x, origin->y );
    137 
    138     /* compute the control box, and grid fit it */
    139     FT_Outline_Get_CBox( outline, &cbox );
    140 
    141     cbox.xMin = FT_PIX_FLOOR( cbox.xMin );
    142     cbox.yMin = FT_PIX_FLOOR( cbox.yMin );
    143     cbox.xMax = FT_PIX_CEIL( cbox.xMax );
    144     cbox.yMax = FT_PIX_CEIL( cbox.yMax );
    145 
    146     if ( cbox.xMin < 0 && cbox.xMax > FT_INT_MAX + cbox.xMin )
    147     {
    148       FT_ERROR(( "ft_smooth_render_generic: glyph too large:"
    149                  " xMin = %d, xMax = %d\n",
    150                  cbox.xMin >> 6, cbox.xMax >> 6 ));
    151       return Smooth_Err_Raster_Overflow;
    152     }
    153     else
    154       width  = ( cbox.xMax - cbox.xMin ) >> 6;
    155 
    156     if ( cbox.yMin < 0 && cbox.yMax > FT_INT_MAX + cbox.yMin )
    157     {
    158       FT_ERROR(( "ft_smooth_render_generic: glyph too large:"
    159                  " yMin = %d, yMax = %d\n",
    160                  cbox.yMin >> 6, cbox.yMax >> 6 ));
    161       return Smooth_Err_Raster_Overflow;
    162     }
    163     else
    164       height = ( cbox.yMax - cbox.yMin ) >> 6;
    165 
    166     bitmap = &slot->bitmap;
    167     memory = render->root.memory;
    168 
    169 #ifndef FT_CONFIG_OPTION_SUBPIXEL_RENDERING
    170     width_org  = width;
    171     height_org = height;
    172 #endif
    173 
    174     /* release old bitmap buffer */
    175     if ( slot->internal->flags & FT_GLYPH_OWN_BITMAP )
    176     {
    177       FT_FREE( bitmap->buffer );
    178       slot->internal->flags &= ~FT_GLYPH_OWN_BITMAP;
    179     }
    180 
    181     /* allocate new one */
    182     pitch = width;
    183     if ( hmul )
    184     {
    185       width = width * 3;
    186       pitch = FT_PAD_CEIL( width, 4 );
    187     }
    188 
    189     if ( vmul )
    190       height *= 3;
    191 
    192     x_shift = (FT_Int) cbox.xMin;
    193     y_shift = (FT_Int) cbox.yMin;
    194     x_left  = (FT_Int)( cbox.xMin >> 6 );
    195     y_top   = (FT_Int)( cbox.yMax >> 6 );
    196 
    197 #ifdef FT_CONFIG_OPTION_SUBPIXEL_RENDERING
    198 
    199     if ( slot->library->lcd_filter_func )
    200     {
    201       FT_Int  extra = slot->library->lcd_extra;
    202 
    203 
    204       if ( hmul )
    205       {
    206         x_shift -= 64 * ( extra >> 1 );
    207         width   += 3 * extra;
    208         pitch    = FT_PAD_CEIL( width, 4 );
    209         x_left  -= extra >> 1;
    210       }
    211 
    212       if ( vmul )
    213       {
    214         y_shift -= 64 * ( extra >> 1 );
    215         height  += 3 * extra;
    216         y_top   += extra >> 1;
    217       }
    218     }
    219 
    220 #endif
    221 
    222 #if FT_UINT_MAX > 0xFFFFU
    223 
    224     /* Required check is ( pitch * height < FT_ULONG_MAX ),     */
    225     /* but we care realistic cases only. Always pitch <= width. */
    226     if ( width > 0x7FFF || height > 0x7FFF )
    227     {
    228       FT_ERROR(( "ft_smooth_render_generic: glyph too large: %u x %u\n",
    229                  width, height ));
    230       return Smooth_Err_Raster_Overflow;
    231     }
    232 
    233 #endif
    234 
    235     bitmap->pixel_mode = FT_PIXEL_MODE_GRAY;
    236     bitmap->num_grays  = 256;
    237     bitmap->width      = width;
    238     bitmap->rows       = height;
    239     bitmap->pitch      = pitch;
    240 
    241     /* translate outline to render it into the bitmap */
    242     FT_Outline_Translate( outline, -x_shift, -y_shift );
    243 
    244     if ( FT_ALLOC( bitmap->buffer, (FT_ULong)pitch * height ) )
    245       goto Exit;
    246 
    247     slot->internal->flags |= FT_GLYPH_OWN_BITMAP;
    248 
    249     /* set up parameters */
    250     params.target = bitmap;
    251     params.source = outline;
    252     params.flags  = FT_RASTER_FLAG_AA;
    253 
    254 #ifdef FT_CONFIG_OPTION_SUBPIXEL_RENDERING
    255 
    256     /* implode outline if needed */
    257     {
    258       FT_Vector*  points     = outline->points;
    259       FT_Vector*  points_end = points + outline->n_points;
    260       FT_Vector*  vec;
    261 
    262 
    263       if ( hmul )
    264         for ( vec = points; vec < points_end; vec++ )
    265           vec->x *= 3;
    266 
    267       if ( vmul )
    268         for ( vec = points; vec < points_end; vec++ )
    269           vec->y *= 3;
    270     }
    271 
    272     /* render outline into the bitmap */
    273     error = render->raster_render( render->raster, &params );
    274 
    275     /* deflate outline if needed */
    276     {
    277       FT_Vector*  points     = outline->points;
    278       FT_Vector*  points_end = points + outline->n_points;
    279       FT_Vector*  vec;
    280 
    281 
    282       if ( hmul )
    283         for ( vec = points; vec < points_end; vec++ )
    284           vec->x /= 3;
    285 
    286       if ( vmul )
    287         for ( vec = points; vec < points_end; vec++ )
    288           vec->y /= 3;
    289     }
    290 
    291     if ( slot->library->lcd_filter_func )
    292       slot->library->lcd_filter_func( bitmap, mode, slot->library );
    293 
    294 #else /* !FT_CONFIG_OPTION_SUBPIXEL_RENDERING */
    295 
    296     /* render outline into bitmap */
    297     error = render->raster_render( render->raster, &params );
    298 
    299     /* expand it horizontally */
    300     if ( hmul )
    301     {
    302       FT_Byte*  line = bitmap->buffer;
    303       FT_UInt   hh;
    304 
    305 
    306       for ( hh = height_org; hh > 0; hh--, line += pitch )
    307       {
    308         FT_UInt   xx;
    309         FT_Byte*  end = line + width;
    310 
    311 
    312         for ( xx = width_org; xx > 0; xx-- )
    313         {
    314           FT_UInt  pixel = line[xx-1];
    315 
    316 
    317           end[-3] = (FT_Byte)pixel;
    318           end[-2] = (FT_Byte)pixel;
    319           end[-1] = (FT_Byte)pixel;
    320           end    -= 3;
    321         }
    322       }
    323     }
    324 
    325     /* expand it vertically */
    326     if ( vmul )
    327     {
    328       FT_Byte*  read  = bitmap->buffer + ( height - height_org ) * pitch;
    329       FT_Byte*  write = bitmap->buffer;
    330       FT_UInt   hh;
    331 
    332 
    333       for ( hh = height_org; hh > 0; hh-- )
    334       {
    335         ft_memcpy( write, read, pitch );
    336         write += pitch;
    337 
    338         ft_memcpy( write, read, pitch );
    339         write += pitch;
    340 
    341         ft_memcpy( write, read, pitch );
    342         write += pitch;
    343         read  += pitch;
    344       }
    345     }
    346 
    347 #endif /* !FT_CONFIG_OPTION_SUBPIXEL_RENDERING */
    348 
    349     FT_Outline_Translate( outline, x_shift, y_shift );
    350 
    351     /*
    352      * XXX: on 16bit system, we return an error for huge bitmap
    353      * to prevent an overflow.
    354      */
    355     if ( x_left > FT_INT_MAX || y_top > FT_INT_MAX )
    356       return Smooth_Err_Invalid_Pixel_Size;
    357 
    358     if ( error )
    359       goto Exit;
    360 
    361     slot->format      = FT_GLYPH_FORMAT_BITMAP;
    362     slot->bitmap_left = (FT_Int)x_left;
    363     slot->bitmap_top  = (FT_Int)y_top;
    364 
    365   Exit:
    366     if ( outline && origin )
    367       FT_Outline_Translate( outline, -origin->x, -origin->y );
    368 
    369     return error;
    370   }
    371 
    372 
    373   /* convert a slot's glyph image into a bitmap */
    374   static FT_Error
    375   ft_smooth_render( FT_Renderer       render,
    376                     FT_GlyphSlot      slot,
    377                     FT_Render_Mode    mode,
    378                     const FT_Vector*  origin )
    379   {
    380     if ( mode == FT_RENDER_MODE_LIGHT )
    381       mode = FT_RENDER_MODE_NORMAL;
    382 
    383     return ft_smooth_render_generic( render, slot, mode, origin,
    384                                      FT_RENDER_MODE_NORMAL );
    385   }
    386 
    387 
    388   /* convert a slot's glyph image into a horizontal LCD bitmap */
    389   static FT_Error
    390   ft_smooth_render_lcd( FT_Renderer       render,
    391                         FT_GlyphSlot      slot,
    392                         FT_Render_Mode    mode,
    393                         const FT_Vector*  origin )
    394   {
    395     FT_Error  error;
    396 
    397     error = ft_smooth_render_generic( render, slot, mode, origin,
    398                                       FT_RENDER_MODE_LCD );
    399     if ( !error )
    400       slot->bitmap.pixel_mode = FT_PIXEL_MODE_LCD;
    401 
    402     return error;
    403   }
    404 
    405 
    406   /* convert a slot's glyph image into a vertical LCD bitmap */
    407   static FT_Error
    408   ft_smooth_render_lcd_v( FT_Renderer       render,
    409                           FT_GlyphSlot      slot,
    410                           FT_Render_Mode    mode,
    411                           const FT_Vector*  origin )
    412   {
    413     FT_Error  error;
    414 
    415     error = ft_smooth_render_generic( render, slot, mode, origin,
    416                                       FT_RENDER_MODE_LCD_V );
    417     if ( !error )
    418       slot->bitmap.pixel_mode = FT_PIXEL_MODE_LCD_V;
    419 
    420     return error;
    421   }
    422 
    423 
    424   FT_DEFINE_RENDERER( ft_smooth_renderer_class,
    425 
    426       FT_MODULE_RENDERER,
    427       sizeof ( FT_RendererRec ),
    428 
    429       "smooth",
    430       0x10000L,
    431       0x20000L,
    432 
    433       0,    /* module specific interface */
    434 
    435       (FT_Module_Constructor)ft_smooth_init,
    436       (FT_Module_Destructor) 0,
    437       (FT_Module_Requester)  0
    438     ,
    439 
    440     FT_GLYPH_FORMAT_OUTLINE,
    441 
    442     (FT_Renderer_RenderFunc)   ft_smooth_render,
    443     (FT_Renderer_TransformFunc)ft_smooth_transform,
    444     (FT_Renderer_GetCBoxFunc)  ft_smooth_get_cbox,
    445     (FT_Renderer_SetModeFunc)  ft_smooth_set_mode,
    446 
    447     (FT_Raster_Funcs*)    &FT_GRAYS_RASTER_GET
    448   )
    449 
    450 
    451   FT_DEFINE_RENDERER( ft_smooth_lcd_renderer_class,
    452 
    453       FT_MODULE_RENDERER,
    454       sizeof ( FT_RendererRec ),
    455 
    456       "smooth-lcd",
    457       0x10000L,
    458       0x20000L,
    459 
    460       0,    /* module specific interface */
    461 
    462       (FT_Module_Constructor)ft_smooth_init,
    463       (FT_Module_Destructor) 0,
    464       (FT_Module_Requester)  0
    465     ,
    466 
    467     FT_GLYPH_FORMAT_OUTLINE,
    468 
    469     (FT_Renderer_RenderFunc)   ft_smooth_render_lcd,
    470     (FT_Renderer_TransformFunc)ft_smooth_transform,
    471     (FT_Renderer_GetCBoxFunc)  ft_smooth_get_cbox,
    472     (FT_Renderer_SetModeFunc)  ft_smooth_set_mode,
    473 
    474     (FT_Raster_Funcs*)    &FT_GRAYS_RASTER_GET
    475   )
    476 
    477   FT_DEFINE_RENDERER( ft_smooth_lcdv_renderer_class,
    478 
    479       FT_MODULE_RENDERER,
    480       sizeof ( FT_RendererRec ),
    481 
    482       "smooth-lcdv",
    483       0x10000L,
    484       0x20000L,
    485 
    486       0,    /* module specific interface */
    487 
    488       (FT_Module_Constructor)ft_smooth_init,
    489       (FT_Module_Destructor) 0,
    490       (FT_Module_Requester)  0
    491     ,
    492 
    493     FT_GLYPH_FORMAT_OUTLINE,
    494 
    495     (FT_Renderer_RenderFunc)   ft_smooth_render_lcd_v,
    496     (FT_Renderer_TransformFunc)ft_smooth_transform,
    497     (FT_Renderer_GetCBoxFunc)  ft_smooth_get_cbox,
    498     (FT_Renderer_SetModeFunc)  ft_smooth_set_mode,
    499 
    500     (FT_Raster_Funcs*)    &FT_GRAYS_RASTER_GET
    501   )
    502 
    503 
    504 /* END */
    505