1 /***************************************************************************/
2 /*                                                                         */
3 /*  pshalgo.h                                                              */
4 /*                                                                         */
5 /*    PostScript hinting algorithm (specification).                        */
6 /*                                                                         */
7 /*  Copyright 2001-2003, 2008, 2013 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 #ifndef __PSHALGO_H__
20 #define __PSHALGO_H__
21 
22 
23 #include "pshrec.h"
24 #include "pshglob.h"
25 
26 
27 FT_BEGIN_HEADER
28 
29 
30   /* handle to Hint structure */
31   typedef struct PSH_HintRec_*  PSH_Hint;
32 
33   /* hint bit-flags */
34   typedef enum  PSH_Hint_Flags_
35   {
36     PSH_HINT_GHOST  = PS_HINT_FLAG_GHOST,
37     PSH_HINT_BOTTOM = PS_HINT_FLAG_BOTTOM,
38     PSH_HINT_ACTIVE = 4,
39     PSH_HINT_FITTED = 8
40 
41   } PSH_Hint_Flags;
42 
43 
44 #define psh_hint_is_active( x )  ( ( (x)->flags & PSH_HINT_ACTIVE ) != 0 )
45 #define psh_hint_is_ghost( x )   ( ( (x)->flags & PSH_HINT_GHOST  ) != 0 )
46 #define psh_hint_is_fitted( x )  ( ( (x)->flags & PSH_HINT_FITTED ) != 0 )
47 
48 #define psh_hint_activate( x )    (x)->flags |=  PSH_HINT_ACTIVE
49 #define psh_hint_deactivate( x )  (x)->flags &= ~PSH_HINT_ACTIVE
50 #define psh_hint_set_fitted( x )  (x)->flags |=  PSH_HINT_FITTED
51 
52   /* hint structure */
53   typedef struct  PSH_HintRec_
54   {
55     FT_Int    org_pos;
56     FT_Int    org_len;
57     FT_Pos    cur_pos;
58     FT_Pos    cur_len;
59     FT_UInt   flags;
60     PSH_Hint  parent;
61     FT_Int    order;
62 
63   } PSH_HintRec;
64 
65 
66   /* this is an interpolation zone used for strong points;  */
67   /* weak points are interpolated according to their strong */
68   /* neighbours                                             */
69   typedef struct  PSH_ZoneRec_
70   {
71     FT_Fixed  scale;
72     FT_Fixed  delta;
73     FT_Pos    min;
74     FT_Pos    max;
75 
76   } PSH_ZoneRec, *PSH_Zone;
77 
78 
79   typedef struct  PSH_Hint_TableRec_
80   {
81     FT_UInt        max_hints;
82     FT_UInt        num_hints;
83     PSH_Hint       hints;
84     PSH_Hint*      sort;
85     PSH_Hint*      sort_global;
86     FT_UInt        num_zones;
87     PSH_ZoneRec*   zones;
88     PSH_Zone       zone;
89     PS_Mask_Table  hint_masks;
90     PS_Mask_Table  counter_masks;
91 
92   } PSH_Hint_TableRec, *PSH_Hint_Table;
93 
94 
95   typedef struct PSH_PointRec_*    PSH_Point;
96   typedef struct PSH_ContourRec_*  PSH_Contour;
97 
98   enum
99   {
100     PSH_DIR_NONE  =  4,
101     PSH_DIR_UP    = -1,
102     PSH_DIR_DOWN  =  1,
103     PSH_DIR_LEFT  = -2,
104     PSH_DIR_RIGHT =  2
105   };
106 
107 #define PSH_DIR_HORIZONTAL  2
108 #define PSH_DIR_VERTICAL    1
109 
110 #define PSH_DIR_COMPARE( d1, d2 )   ( (d1) == (d2) || (d1) == -(d2) )
111 #define PSH_DIR_IS_HORIZONTAL( d )  PSH_DIR_COMPARE( d, PSH_DIR_HORIZONTAL )
112 #define PSH_DIR_IS_VERTICAL( d )    PSH_DIR_COMPARE( d, PSH_DIR_VERTICAL )
113 
114 
115  /* the following bit-flags are computed once by the glyph */
116  /* analyzer, for both dimensions                          */
117   enum
118   {
119     PSH_POINT_OFF    = 1,   /* point is off the curve */
120     PSH_POINT_SMOOTH = 2,   /* point is smooth        */
121     PSH_POINT_INFLEX = 4    /* point is inflection    */
122   };
123 
124 #define psh_point_is_smooth( p )  ( (p)->flags & PSH_POINT_SMOOTH )
125 #define psh_point_is_off( p )     ( (p)->flags & PSH_POINT_OFF    )
126 #define psh_point_is_inflex( p )  ( (p)->flags & PSH_POINT_INFLEX )
127 
128 #define psh_point_set_smooth( p )  (p)->flags |= PSH_POINT_SMOOTH
129 #define psh_point_set_off( p )     (p)->flags |= PSH_POINT_OFF
130 #define psh_point_set_inflex( p )  (p)->flags |= PSH_POINT_INFLEX
131 
132   /* the following bit-flags are re-computed for each dimension */
133   enum
134   {
135     PSH_POINT_STRONG   = 16,   /* point is strong                           */
136     PSH_POINT_FITTED   = 32,   /* point is already fitted                   */
137     PSH_POINT_EXTREMUM = 64,   /* point is local extremum                   */
138     PSH_POINT_POSITIVE = 128,  /* extremum has positive contour flow        */
139     PSH_POINT_NEGATIVE = 256,  /* extremum has negative contour flow        */
140     PSH_POINT_EDGE_MIN = 512,  /* point is aligned to left/bottom stem edge */
141     PSH_POINT_EDGE_MAX = 1024  /* point is aligned to top/right stem edge   */
142   };
143 
144 #define psh_point_is_strong( p )    ( (p)->flags2 & PSH_POINT_STRONG )
145 #define psh_point_is_fitted( p )    ( (p)->flags2 & PSH_POINT_FITTED )
146 #define psh_point_is_extremum( p )  ( (p)->flags2 & PSH_POINT_EXTREMUM )
147 #define psh_point_is_positive( p )  ( (p)->flags2 & PSH_POINT_POSITIVE )
148 #define psh_point_is_negative( p )  ( (p)->flags2 & PSH_POINT_NEGATIVE )
149 #define psh_point_is_edge_min( p )  ( (p)->flags2 & PSH_POINT_EDGE_MIN )
150 #define psh_point_is_edge_max( p )  ( (p)->flags2 & PSH_POINT_EDGE_MAX )
151 
152 #define psh_point_set_strong( p )    (p)->flags2 |= PSH_POINT_STRONG
153 #define psh_point_set_fitted( p )    (p)->flags2 |= PSH_POINT_FITTED
154 #define psh_point_set_extremum( p )  (p)->flags2 |= PSH_POINT_EXTREMUM
155 #define psh_point_set_positive( p )  (p)->flags2 |= PSH_POINT_POSITIVE
156 #define psh_point_set_negative( p )  (p)->flags2 |= PSH_POINT_NEGATIVE
157 #define psh_point_set_edge_min( p )  (p)->flags2 |= PSH_POINT_EDGE_MIN
158 #define psh_point_set_edge_max( p )  (p)->flags2 |= PSH_POINT_EDGE_MAX
159 
160 
161   typedef struct  PSH_PointRec_
162   {
163     PSH_Point    prev;
164     PSH_Point    next;
165     PSH_Contour  contour;
166     FT_UInt      flags;
167     FT_UInt      flags2;
168     FT_Char      dir_in;
169     FT_Char      dir_out;
170     PSH_Hint     hint;
171     FT_Pos       org_u;
172     FT_Pos       org_v;
173     FT_Pos       cur_u;
174 #ifdef DEBUG_HINTER
175     FT_Pos       org_x;
176     FT_Pos       cur_x;
177     FT_Pos       org_y;
178     FT_Pos       cur_y;
179     FT_UInt      flags_x;
180     FT_UInt      flags_y;
181 #endif
182 
183   } PSH_PointRec;
184 
185 
186   typedef struct  PSH_ContourRec_
187   {
188     PSH_Point  start;
189     FT_UInt    count;
190 
191   } PSH_ContourRec;
192 
193 
194   typedef struct  PSH_GlyphRec_
195   {
196     FT_UInt            num_points;
197     FT_UInt            num_contours;
198 
199     PSH_Point          points;
200     PSH_Contour        contours;
201 
202     FT_Memory          memory;
203     FT_Outline*        outline;
204     PSH_Globals        globals;
205     PSH_Hint_TableRec  hint_tables[2];
206 
207     FT_Bool            vertical;
208     FT_Int             major_dir;
209     FT_Int             minor_dir;
210 
211     FT_Bool            do_horz_hints;
212     FT_Bool            do_vert_hints;
213     FT_Bool            do_horz_snapping;
214     FT_Bool            do_vert_snapping;
215     FT_Bool            do_stem_adjust;
216 
217   } PSH_GlyphRec, *PSH_Glyph;
218 
219 
220 #ifdef DEBUG_HINTER
221   extern PSH_Hint_Table  ps_debug_hint_table;
222 
223   typedef void
224   (*PSH_HintFunc)( PSH_Hint  hint,
225                    FT_Bool   vertical );
226 
227   extern PSH_HintFunc    ps_debug_hint_func;
228 
229   extern PSH_Glyph       ps_debug_glyph;
230 #endif
231 
232 
233   extern FT_Error
234   ps_hints_apply( PS_Hints        ps_hints,
235                   FT_Outline*     outline,
236                   PSH_Globals     globals,
237                   FT_Render_Mode  hint_mode );
238 
239 
240 FT_END_HEADER
241 
242 
243 #endif /* __PSHALGO_H__ */
244 
245 
246 /* END */
247