xref: /inferno-os/libfreetype/ftsmooth.c (revision 46439007cf417cbd9ac8049bb4122c890097a0fa)
1 /***************************************************************************/
2 /*                                                                         */
3 /*  ftsmooth.c                                                             */
4 /*                                                                         */
5 /*    Anti-aliasing renderer interface (body).                             */
6 /*                                                                         */
7 /*  Copyright 2000-2001, 2002 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_OBJECTS_H
21 #include FT_OUTLINE_H
22 #include "ftsmooth.h"
23 #include "ftgrays.h"
24 
25 #include "ftsmerrs.h"
26 
27 
28   /* initialize renderer -- init its raster */
29   static FT_Error
30   ft_smooth_init( FT_Renderer  render )
31   {
32     FT_Library  library = FT_MODULE_LIBRARY( render );
33 
34 
35     render->clazz->raster_class->raster_reset( render->raster,
36                                                library->raster_pool,
37                                                library->raster_pool_size );
38 
39     return 0;
40   }
41 
42 
43   /* sets render-specific mode */
44   static FT_Error
45   ft_smooth_set_mode( FT_Renderer  render,
46                       FT_ULong     mode_tag,
47                       FT_Pointer   data )
48   {
49     /* we simply pass it to the raster */
50     return render->clazz->raster_class->raster_set_mode( render->raster,
51                                                          mode_tag,
52                                                          data );
53   }
54 
55   /* transform a given glyph image */
56   static FT_Error
57   ft_smooth_transform( FT_Renderer   render,
58                        FT_GlyphSlot  slot,
59                        FT_Matrix*    matrix,
60                        FT_Vector*    delta )
61   {
62     FT_Error  error = Smooth_Err_Ok;
63 
64 
65     if ( slot->format != render->glyph_format )
66     {
67       error = Smooth_Err_Invalid_Argument;
68       goto Exit;
69     }
70 
71     if ( matrix )
72       FT_Outline_Transform( &slot->outline, matrix );
73 
74     if ( delta )
75       FT_Outline_Translate( &slot->outline, delta->x, delta->y );
76 
77   Exit:
78     return error;
79   }
80 
81 
82   /* return the glyph's control box */
83   static void
84   ft_smooth_get_cbox( FT_Renderer   render,
85                       FT_GlyphSlot  slot,
86                       FT_BBox*      cbox )
87   {
88     FT_MEM_ZERO( cbox, sizeof ( *cbox ) );
89 
90     if ( slot->format == render->glyph_format )
91       FT_Outline_Get_CBox( &slot->outline, cbox );
92   }
93 
94 
95   /* convert a slot's glyph image into a bitmap */
96   static FT_Error
97   ft_smooth_render_generic( FT_Renderer     render,
98                             FT_GlyphSlot    slot,
99                             FT_Render_Mode  mode,
100                             FT_Vector*      origin,
101                             FT_Render_Mode  required_mode,
102                             FT_Int          hmul,
103                             FT_Int          vmul )
104   {
105     FT_Error     error;
106     FT_Outline*  outline = NULL;
107     FT_BBox      cbox;
108     FT_UInt      width, height, pitch;
109     FT_Bitmap*   bitmap;
110     FT_Memory    memory;
111 
112     FT_Raster_Params  params;
113 
114 
115     /* check glyph image format */
116     if ( slot->format != render->glyph_format )
117     {
118       error = Smooth_Err_Invalid_Argument;
119       goto Exit;
120     }
121 
122     /* check mode */
123     if ( mode != required_mode )
124       return Smooth_Err_Cannot_Render_Glyph;
125 
126     outline = &slot->outline;
127 
128     /* translate the outline to the new origin if needed */
129     if ( origin )
130       FT_Outline_Translate( outline, origin->x, origin->y );
131 
132     /* compute the control box, and grid fit it */
133     FT_Outline_Get_CBox( outline, &cbox );
134 
135     cbox.xMin &= -64;
136     cbox.yMin &= -64;
137     cbox.xMax  = ( cbox.xMax + 63 ) & -64;
138     cbox.yMax  = ( cbox.yMax + 63 ) & -64;
139 
140     width  = ( cbox.xMax - cbox.xMin ) >> 6;
141     height = ( cbox.yMax - cbox.yMin ) >> 6;
142     bitmap = &slot->bitmap;
143     memory = render->root.memory;
144 
145     /* release old bitmap buffer */
146     if ( slot->flags & FT_GLYPH_OWN_BITMAP )
147     {
148       FT_FREE( bitmap->buffer );
149       slot->flags &= ~FT_GLYPH_OWN_BITMAP;
150     }
151 
152     /* allocate new one, depends on pixel format */
153     pitch = width;
154     if ( hmul )
155     {
156       width = width * hmul;
157       pitch = ( width + 3 ) & -4;
158     }
159 
160     if ( vmul )
161       height *= vmul;
162 
163     bitmap->pixel_mode = FT_PIXEL_MODE_GRAY;
164     bitmap->num_grays  = 256;
165     bitmap->width      = width;
166     bitmap->rows       = height;
167     bitmap->pitch      = pitch;
168 
169     if ( FT_ALLOC( bitmap->buffer, (FT_ULong)pitch * height ) )
170       goto Exit;
171 
172     slot->flags |= FT_GLYPH_OWN_BITMAP;
173 
174     /* translate outline to render it into the bitmap */
175     FT_Outline_Translate( outline, -cbox.xMin, -cbox.yMin );
176 
177     /* set up parameters */
178     params.target = bitmap;
179     params.source = outline;
180     params.flags  = FT_RASTER_FLAG_AA;
181 
182     /* implode outline if needed */
183     {
184       FT_Int      n;
185       FT_Vector*  vec;
186 
187 
188       if ( hmul )
189         for ( vec = outline->points, n = 0; n < outline->n_points; n++, vec++ )
190           vec->x *= hmul;
191 
192       if ( vmul )
193         for ( vec = outline->points, n = 0; n < outline->n_points; n++, vec++ )
194           vec->y *= vmul;
195     }
196 
197     /* render outline into the bitmap */
198     error = render->raster_render( render->raster, &params );
199 
200     /* deflate outline if needed */
201     {
202       FT_Int      n;
203       FT_Vector*  vec;
204 
205 
206       if ( hmul )
207         for ( vec = outline->points, n = 0; n < outline->n_points; n++, vec++ )
208           vec->x /= hmul;
209 
210       if ( vmul )
211         for ( vec = outline->points, n = 0; n < outline->n_points; n++, vec++ )
212           vec->y /= vmul;
213     }
214 
215     FT_Outline_Translate( outline, cbox.xMin, cbox.yMin );
216 
217     if ( error )
218       goto Exit;
219 
220     slot->format      = FT_GLYPH_FORMAT_BITMAP;
221     slot->bitmap_left = (FT_Int)( cbox.xMin >> 6 );
222     slot->bitmap_top  = (FT_Int)( cbox.yMax >> 6 );
223 
224   Exit:
225     if ( outline && origin )
226       FT_Outline_Translate( outline, -origin->x, -origin->y );
227 
228     return error;
229   }
230 
231 
232   /* convert a slot's glyph image into a bitmap */
233   static FT_Error
234   ft_smooth_render( FT_Renderer     render,
235                     FT_GlyphSlot    slot,
236                     FT_Render_Mode  mode,
237                     FT_Vector*      origin )
238   {
239     return ft_smooth_render_generic( render, slot, mode, origin,
240                                      FT_RENDER_MODE_NORMAL,
241                                      0, 0 );
242   }
243 
244 
245   /* convert a slot's glyph image into a horizontal LCD bitmap */
246   static FT_Error
247   ft_smooth_render_lcd( FT_Renderer     render,
248                         FT_GlyphSlot    slot,
249                         FT_Render_Mode  mode,
250                         FT_Vector*      origin )
251   {
252     FT_Error  error;
253 
254     error = ft_smooth_render_generic( render, slot, mode, origin,
255                                       FT_RENDER_MODE_LCD,
256                                       3, 0 );
257     if ( !error )
258       slot->bitmap.pixel_mode = FT_PIXEL_MODE_LCD;
259 
260     return error;
261   }
262 
263 
264   /* convert a slot's glyph image into a vertical LCD bitmap */
265   static FT_Error
266   ft_smooth_render_lcd_v( FT_Renderer     render,
267                           FT_GlyphSlot    slot,
268                           FT_Render_Mode  mode,
269                           FT_Vector*      origin )
270   {
271     FT_Error  error;
272 
273     error = ft_smooth_render_generic( render, slot, mode, origin,
274                                       FT_RENDER_MODE_LCD_V,
275                                       0, 3 );
276     if ( !error )
277       slot->bitmap.pixel_mode = FT_PIXEL_MODE_LCD_V;
278 
279     return error;
280   }
281 
282 
283   FT_CALLBACK_TABLE_DEF
284   const FT_Renderer_Class  ft_smooth_renderer_class =
285   {
286     {
287       ft_module_renderer,
288       sizeof( FT_RendererRec ),
289 
290       "smooth",
291       0x10000L,
292       0x20000L,
293 
294       0,    /* module specific interface */
295 
296       (FT_Module_Constructor)ft_smooth_init,
297       (FT_Module_Destructor) 0,
298       (FT_Module_Requester)  0
299     },
300 
301     FT_GLYPH_FORMAT_OUTLINE,
302 
303     (FT_Renderer_RenderFunc)   ft_smooth_render,
304     (FT_Renderer_TransformFunc)ft_smooth_transform,
305     (FT_Renderer_GetCBoxFunc)  ft_smooth_get_cbox,
306     (FT_Renderer_SetModeFunc)  ft_smooth_set_mode,
307 
308     (FT_Raster_Funcs*)    &ft_grays_raster
309   };
310 
311 
312   FT_CALLBACK_TABLE_DEF
313   const FT_Renderer_Class  ft_smooth_lcd_renderer_class =
314   {
315     {
316       ft_module_renderer,
317       sizeof( FT_RendererRec ),
318 
319       "smooth-lcd",
320       0x10000L,
321       0x20000L,
322 
323       0,    /* module specific interface */
324 
325       (FT_Module_Constructor)ft_smooth_init,
326       (FT_Module_Destructor) 0,
327       (FT_Module_Requester)  0
328     },
329 
330     FT_GLYPH_FORMAT_OUTLINE,
331 
332     (FT_Renderer_RenderFunc)   ft_smooth_render_lcd,
333     (FT_Renderer_TransformFunc)ft_smooth_transform,
334     (FT_Renderer_GetCBoxFunc)  ft_smooth_get_cbox,
335     (FT_Renderer_SetModeFunc)  ft_smooth_set_mode,
336 
337     (FT_Raster_Funcs*)    &ft_grays_raster
338   };
339 
340 
341 
342   FT_CALLBACK_TABLE_DEF
343   const FT_Renderer_Class  ft_smooth_lcdv_renderer_class =
344   {
345     {
346       ft_module_renderer,
347       sizeof( FT_RendererRec ),
348 
349       "smooth-lcdv",
350       0x10000L,
351       0x20000L,
352 
353       0,    /* module specific interface */
354 
355       (FT_Module_Constructor)ft_smooth_init,
356       (FT_Module_Destructor) 0,
357       (FT_Module_Requester)  0
358     },
359 
360     FT_GLYPH_FORMAT_OUTLINE,
361 
362     (FT_Renderer_RenderFunc)   ft_smooth_render_lcd_v,
363     (FT_Renderer_TransformFunc)ft_smooth_transform,
364     (FT_Renderer_GetCBoxFunc)  ft_smooth_get_cbox,
365     (FT_Renderer_SetModeFunc)  ft_smooth_set_mode,
366 
367     (FT_Raster_Funcs*)    &ft_grays_raster
368   };
369 
370 
371 /* END */
372