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1 /***************************************************************************/
2 /*                                                                         */
3 /*  ftsmooth.c                                                             */
4 /*                                                                         */
5 /*    Anti-aliasing renderer interface (body).                             */
6 /*                                                                         */
7 /*  Copyright 2000-2015 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
ft_smooth_init(FT_Renderer render)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
ft_smooth_set_mode(FT_Renderer render,FT_ULong mode_tag,FT_Pointer data)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
ft_smooth_transform(FT_Renderer render,FT_GlyphSlot slot,const FT_Matrix * matrix,const FT_Vector * delta)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 = FT_Err_Ok;
65 
66 
67     if ( slot->format != render->glyph_format )
68     {
69       error = FT_THROW( 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
ft_smooth_get_cbox(FT_Renderer render,FT_GlyphSlot slot,FT_BBox * cbox)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
ft_smooth_render_generic(FT_Renderer render,FT_GlyphSlot slot,FT_Render_Mode mode,const FT_Vector * origin,FT_Render_Mode required_mode)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 = &slot->outline;
107     FT_Bitmap*   bitmap  = &slot->bitmap;
108     FT_Memory    memory  = render->root.memory;
109     FT_BBox      cbox;
110     FT_Pos       x_shift = 0;
111     FT_Pos       y_shift = 0;
112     FT_Pos       x_left, y_top;
113     FT_Pos       width, height, pitch;
114 #ifndef FT_CONFIG_OPTION_SUBPIXEL_RENDERING
115     FT_Pos       height_org, width_org;
116 #endif
117     FT_Int       hmul    = mode == FT_RENDER_MODE_LCD;
118     FT_Int       vmul    = mode == FT_RENDER_MODE_LCD_V;
119 
120     FT_Raster_Params  params;
121 
122     FT_Bool  have_outline_shifted = FALSE;
123     FT_Bool  have_buffer          = FALSE;
124 
125 
126     /* check glyph image format */
127     if ( slot->format != render->glyph_format )
128     {
129       error = FT_THROW( Invalid_Argument );
130       goto Exit;
131     }
132 
133     /* check mode */
134     if ( mode != required_mode )
135     {
136       error = FT_THROW( Cannot_Render_Glyph );
137       goto Exit;
138     }
139 
140     if ( origin )
141     {
142       x_shift = origin->x;
143       y_shift = origin->y;
144     }
145 
146     /* compute the control box, and grid fit it */
147     /* taking into account the origin shift     */
148     FT_Outline_Get_CBox( outline, &cbox );
149 
150     cbox.xMin = FT_PIX_FLOOR( cbox.xMin + x_shift );
151     cbox.yMin = FT_PIX_FLOOR( cbox.yMin + y_shift );
152     cbox.xMax = FT_PIX_CEIL( cbox.xMax + x_shift );
153     cbox.yMax = FT_PIX_CEIL( cbox.yMax + y_shift );
154 
155     x_shift -= cbox.xMin;
156     y_shift -= cbox.yMin;
157 
158     x_left  = cbox.xMin >> 6;
159     y_top   = cbox.yMax >> 6;
160 
161     width  = (FT_ULong)( cbox.xMax - cbox.xMin ) >> 6;
162     height = (FT_ULong)( cbox.yMax - cbox.yMin ) >> 6;
163 
164 #ifndef FT_CONFIG_OPTION_SUBPIXEL_RENDERING
165     width_org  = width;
166     height_org = height;
167 #endif
168 
169     pitch = width;
170     if ( hmul )
171     {
172       width *= 3;
173       pitch  = FT_PAD_CEIL( width, 4 );
174     }
175 
176     if ( vmul )
177       height *= 3;
178 
179 #ifdef FT_CONFIG_OPTION_SUBPIXEL_RENDERING
180 
181     if ( slot->library->lcd_filter_func )
182     {
183       FT_Int  extra = slot->library->lcd_extra;
184 
185 
186       if ( hmul )
187       {
188         x_shift += 64 * ( extra >> 1 );
189         x_left  -= extra >> 1;
190         width   += 3 * extra;
191         pitch    = FT_PAD_CEIL( width, 4 );
192       }
193 
194       if ( vmul )
195       {
196         y_shift += 64 * ( extra >> 1 );
197         y_top   += extra >> 1;
198         height  += 3 * extra;
199       }
200     }
201 
202 #endif
203 
204     /*
205      * XXX: on 16bit system, we return an error for huge bitmap
206      * to prevent an overflow.
207      */
208     if ( x_left > FT_INT_MAX || y_top > FT_INT_MAX ||
209          x_left < FT_INT_MIN || y_top < FT_INT_MIN )
210     {
211       error = FT_THROW( Invalid_Pixel_Size );
212       goto Exit;
213     }
214 
215     /* Required check is (pitch * height < FT_ULONG_MAX),        */
216     /* but we care realistic cases only.  Always pitch <= width. */
217     if ( width > 0x7FFF || height > 0x7FFF )
218     {
219       FT_ERROR(( "ft_smooth_render_generic: glyph too large: %u x %u\n",
220                  width, height ));
221       error = FT_THROW( Raster_Overflow );
222       goto Exit;
223     }
224 
225     /* release old bitmap buffer */
226     if ( slot->internal->flags & FT_GLYPH_OWN_BITMAP )
227     {
228       FT_FREE( bitmap->buffer );
229       slot->internal->flags &= ~FT_GLYPH_OWN_BITMAP;
230     }
231 
232     /* allocate new one */
233     if ( FT_ALLOC( bitmap->buffer, (FT_ULong)( pitch * height ) ) )
234       goto Exit;
235     else
236       have_buffer = TRUE;
237 
238     slot->internal->flags |= FT_GLYPH_OWN_BITMAP;
239 
240     slot->format      = FT_GLYPH_FORMAT_BITMAP;
241     slot->bitmap_left = (FT_Int)x_left;
242     slot->bitmap_top  = (FT_Int)y_top;
243 
244     bitmap->pixel_mode = FT_PIXEL_MODE_GRAY;
245     bitmap->num_grays  = 256;
246     bitmap->width      = (unsigned int)width;
247     bitmap->rows       = (unsigned int)height;
248     bitmap->pitch      = pitch;
249 
250     /* translate outline to render it into the bitmap */
251     if ( x_shift || y_shift )
252     {
253       FT_Outline_Translate( outline, x_shift, y_shift );
254       have_outline_shifted = TRUE;
255     }
256 
257     /* set up parameters */
258     params.target = bitmap;
259     params.source = outline;
260     params.flags  = FT_RASTER_FLAG_AA;
261 
262 #ifdef FT_CONFIG_OPTION_SUBPIXEL_RENDERING
263 
264     /* implode outline if needed */
265     {
266       FT_Vector*  points     = outline->points;
267       FT_Vector*  points_end = points + outline->n_points;
268       FT_Vector*  vec;
269 
270 
271       if ( hmul )
272         for ( vec = points; vec < points_end; vec++ )
273           vec->x *= 3;
274 
275       if ( vmul )
276         for ( vec = points; vec < points_end; vec++ )
277           vec->y *= 3;
278     }
279 
280     /* render outline into the bitmap */
281     error = render->raster_render( render->raster, &params );
282 
283     /* deflate outline if needed */
284     {
285       FT_Vector*  points     = outline->points;
286       FT_Vector*  points_end = points + outline->n_points;
287       FT_Vector*  vec;
288 
289 
290       if ( hmul )
291         for ( vec = points; vec < points_end; vec++ )
292           vec->x /= 3;
293 
294       if ( vmul )
295         for ( vec = points; vec < points_end; vec++ )
296           vec->y /= 3;
297     }
298 
299     if ( error )
300       goto Exit;
301 
302     if ( slot->library->lcd_filter_func )
303       slot->library->lcd_filter_func( bitmap, mode, slot->library );
304 
305 #else /* !FT_CONFIG_OPTION_SUBPIXEL_RENDERING */
306 
307     /* render outline into bitmap */
308     error = render->raster_render( render->raster, &params );
309     if ( error )
310       goto Exit;
311 
312     /* expand it horizontally */
313     if ( hmul )
314     {
315       FT_Byte*  line = bitmap->buffer;
316       FT_UInt   hh;
317 
318 
319       for ( hh = height_org; hh > 0; hh--, line += pitch )
320       {
321         FT_UInt   xx;
322         FT_Byte*  end = line + width;
323 
324 
325         for ( xx = width_org; xx > 0; xx-- )
326         {
327           FT_UInt  pixel = line[xx-1];
328 
329 
330           end[-3] = (FT_Byte)pixel;
331           end[-2] = (FT_Byte)pixel;
332           end[-1] = (FT_Byte)pixel;
333           end    -= 3;
334         }
335       }
336     }
337 
338     /* expand it vertically */
339     if ( vmul )
340     {
341       FT_Byte*  read  = bitmap->buffer + ( height - height_org ) * pitch;
342       FT_Byte*  write = bitmap->buffer;
343       FT_UInt   hh;
344 
345 
346       for ( hh = height_org; hh > 0; hh-- )
347       {
348         ft_memcpy( write, read, pitch );
349         write += pitch;
350 
351         ft_memcpy( write, read, pitch );
352         write += pitch;
353 
354         ft_memcpy( write, read, pitch );
355         write += pitch;
356         read  += pitch;
357       }
358     }
359 
360 #endif /* !FT_CONFIG_OPTION_SUBPIXEL_RENDERING */
361 
362     /* everything is fine; don't deallocate buffer */
363     have_buffer = FALSE;
364 
365     error = FT_Err_Ok;
366 
367   Exit:
368     if ( have_outline_shifted )
369       FT_Outline_Translate( outline, -x_shift, -y_shift );
370     if ( have_buffer )
371     {
372       FT_FREE( bitmap->buffer );
373       slot->internal->flags &= ~FT_GLYPH_OWN_BITMAP;
374     }
375 
376     return error;
377   }
378 
379 
380   /* convert a slot's glyph image into a bitmap */
381   static FT_Error
ft_smooth_render(FT_Renderer render,FT_GlyphSlot slot,FT_Render_Mode mode,const FT_Vector * origin)382   ft_smooth_render( FT_Renderer       render,
383                     FT_GlyphSlot      slot,
384                     FT_Render_Mode    mode,
385                     const FT_Vector*  origin )
386   {
387     if ( mode == FT_RENDER_MODE_LIGHT )
388       mode = FT_RENDER_MODE_NORMAL;
389 
390     return ft_smooth_render_generic( render, slot, mode, origin,
391                                      FT_RENDER_MODE_NORMAL );
392   }
393 
394 
395   /* convert a slot's glyph image into a horizontal LCD bitmap */
396   static FT_Error
ft_smooth_render_lcd(FT_Renderer render,FT_GlyphSlot slot,FT_Render_Mode mode,const FT_Vector * origin)397   ft_smooth_render_lcd( FT_Renderer       render,
398                         FT_GlyphSlot      slot,
399                         FT_Render_Mode    mode,
400                         const FT_Vector*  origin )
401   {
402     FT_Error  error;
403 
404     error = ft_smooth_render_generic( render, slot, mode, origin,
405                                       FT_RENDER_MODE_LCD );
406     if ( !error )
407       slot->bitmap.pixel_mode = FT_PIXEL_MODE_LCD;
408 
409     return error;
410   }
411 
412 
413   /* convert a slot's glyph image into a vertical LCD bitmap */
414   static FT_Error
ft_smooth_render_lcd_v(FT_Renderer render,FT_GlyphSlot slot,FT_Render_Mode mode,const FT_Vector * origin)415   ft_smooth_render_lcd_v( FT_Renderer       render,
416                           FT_GlyphSlot      slot,
417                           FT_Render_Mode    mode,
418                           const FT_Vector*  origin )
419   {
420     FT_Error  error;
421 
422     error = ft_smooth_render_generic( render, slot, mode, origin,
423                                       FT_RENDER_MODE_LCD_V );
424     if ( !error )
425       slot->bitmap.pixel_mode = FT_PIXEL_MODE_LCD_V;
426 
427     return error;
428   }
429 
430 
431   FT_DEFINE_RENDERER( ft_smooth_renderer_class,
432 
433       FT_MODULE_RENDERER,
434       sizeof ( FT_RendererRec ),
435 
436       "smooth",
437       0x10000L,
438       0x20000L,
439 
440       0,    /* module specific interface */
441 
442       (FT_Module_Constructor)ft_smooth_init,
443       (FT_Module_Destructor) 0,
444       (FT_Module_Requester)  0
445     ,
446 
447     FT_GLYPH_FORMAT_OUTLINE,
448 
449     (FT_Renderer_RenderFunc)   ft_smooth_render,
450     (FT_Renderer_TransformFunc)ft_smooth_transform,
451     (FT_Renderer_GetCBoxFunc)  ft_smooth_get_cbox,
452     (FT_Renderer_SetModeFunc)  ft_smooth_set_mode,
453 
454     (FT_Raster_Funcs*)    &FT_GRAYS_RASTER_GET
455   )
456 
457 
458   FT_DEFINE_RENDERER( ft_smooth_lcd_renderer_class,
459 
460       FT_MODULE_RENDERER,
461       sizeof ( FT_RendererRec ),
462 
463       "smooth-lcd",
464       0x10000L,
465       0x20000L,
466 
467       0,    /* module specific interface */
468 
469       (FT_Module_Constructor)ft_smooth_init,
470       (FT_Module_Destructor) 0,
471       (FT_Module_Requester)  0
472     ,
473 
474     FT_GLYPH_FORMAT_OUTLINE,
475 
476     (FT_Renderer_RenderFunc)   ft_smooth_render_lcd,
477     (FT_Renderer_TransformFunc)ft_smooth_transform,
478     (FT_Renderer_GetCBoxFunc)  ft_smooth_get_cbox,
479     (FT_Renderer_SetModeFunc)  ft_smooth_set_mode,
480 
481     (FT_Raster_Funcs*)    &FT_GRAYS_RASTER_GET
482   )
483 
484   FT_DEFINE_RENDERER( ft_smooth_lcdv_renderer_class,
485 
486       FT_MODULE_RENDERER,
487       sizeof ( FT_RendererRec ),
488 
489       "smooth-lcdv",
490       0x10000L,
491       0x20000L,
492 
493       0,    /* module specific interface */
494 
495       (FT_Module_Constructor)ft_smooth_init,
496       (FT_Module_Destructor) 0,
497       (FT_Module_Requester)  0
498     ,
499 
500     FT_GLYPH_FORMAT_OUTLINE,
501 
502     (FT_Renderer_RenderFunc)   ft_smooth_render_lcd_v,
503     (FT_Renderer_TransformFunc)ft_smooth_transform,
504     (FT_Renderer_GetCBoxFunc)  ft_smooth_get_cbox,
505     (FT_Renderer_SetModeFunc)  ft_smooth_set_mode,
506 
507     (FT_Raster_Funcs*)    &FT_GRAYS_RASTER_GET
508   )
509 
510 
511 /* END */
512