1 /****************************************************************************
2 *
3 * pshalgo.h
4 *
5 * PostScript hinting algorithm (specification).
6 *
7 * Copyright (C) 2001-2023 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
34 /* hint bit-flags */
35 #define PSH_HINT_GHOST PS_HINT_FLAG_GHOST
36 #define PSH_HINT_BOTTOM PS_HINT_FLAG_BOTTOM
37 #define PSH_HINT_ACTIVE 4U
38 #define PSH_HINT_FITTED 8U
39
40
41 #define psh_hint_is_active( x ) ( ( (x)->flags & PSH_HINT_ACTIVE ) != 0 )
42 #define psh_hint_is_ghost( x ) ( ( (x)->flags & PSH_HINT_GHOST ) != 0 )
43 #define psh_hint_is_fitted( x ) ( ( (x)->flags & PSH_HINT_FITTED ) != 0 )
44
45 #define psh_hint_activate( x ) (x)->flags |= PSH_HINT_ACTIVE
46 #define psh_hint_deactivate( x ) (x)->flags &= ~PSH_HINT_ACTIVE
47 #define psh_hint_set_fitted( x ) (x)->flags |= PSH_HINT_FITTED
48
49
50 /* hint structure */
51 typedef struct PSH_HintRec_
52 {
53 FT_Int org_pos;
54 FT_Int org_len;
55 FT_Pos cur_pos;
56 FT_Pos cur_len;
57 FT_UInt flags;
58 PSH_Hint parent;
59 FT_Int order;
60
61 } PSH_HintRec;
62
63
64 /* this is an interpolation zone used for strong points; */
65 /* weak points are interpolated according to their strong */
66 /* neighbours */
67 typedef struct PSH_ZoneRec_
68 {
69 FT_Fixed scale;
70 FT_Fixed delta;
71 FT_Pos min;
72 FT_Pos max;
73
74 } PSH_ZoneRec, *PSH_Zone;
75
76
77 typedef struct PSH_Hint_TableRec_
78 {
79 FT_UInt max_hints;
80 FT_UInt num_hints;
81 PSH_Hint hints;
82 PSH_Hint* sort;
83 PSH_Hint* sort_global;
84 FT_UInt num_zones;
85 PSH_ZoneRec* zones;
86 PSH_Zone zone;
87 PS_Mask_Table hint_masks;
88 PS_Mask_Table counter_masks;
89
90 } PSH_Hint_TableRec, *PSH_Hint_Table;
91
92
93 typedef struct PSH_PointRec_* PSH_Point;
94 typedef struct PSH_ContourRec_* PSH_Contour;
95
96 typedef enum PSH_Dir_
97 {
98 PSH_DIR_NONE = 0,
99 PSH_DIR_UP = 1,
100 PSH_DIR_DOWN = 2,
101 PSH_DIR_VERTICAL = 1 | 2,
102 PSH_DIR_LEFT = 4,
103 PSH_DIR_RIGHT = 8,
104 PSH_DIR_HORIZONTAL = 4 | 8
105
106 } PSH_Dir;
107
108
109 /* the following bit-flags are computed once by the glyph */
110 /* analyzer, for both dimensions */
111 #define PSH_POINT_OFF 1U /* point is off the curve */
112 #define PSH_POINT_SMOOTH 2U /* point is smooth */
113 #define PSH_POINT_INFLEX 4U /* point is inflection */
114
115
116 #define psh_point_is_smooth( p ) ( (p)->flags & PSH_POINT_SMOOTH )
117 #define psh_point_is_off( p ) ( (p)->flags & PSH_POINT_OFF )
118 #define psh_point_is_inflex( p ) ( (p)->flags & PSH_POINT_INFLEX )
119
120 #define psh_point_set_smooth( p ) (p)->flags |= PSH_POINT_SMOOTH
121 #define psh_point_set_off( p ) (p)->flags |= PSH_POINT_OFF
122 #define psh_point_set_inflex( p ) (p)->flags |= PSH_POINT_INFLEX
123
124
125 /* the following bit-flags are re-computed for each dimension */
126 #define PSH_POINT_STRONG 16U /* point is strong */
127 #define PSH_POINT_FITTED 32U /* point is already fitted */
128 #define PSH_POINT_EXTREMUM 64U /* point is local extremum */
129 #define PSH_POINT_POSITIVE 128U /* extremum has positive contour flow */
130 #define PSH_POINT_NEGATIVE 256U /* extremum has negative contour flow */
131 #define PSH_POINT_EDGE_MIN 512U /* point is aligned to left/bottom stem edge */
132 #define PSH_POINT_EDGE_MAX 1024U /* point is aligned to top/right stem edge */
133
134
135 #define psh_point_is_strong( p ) ( (p)->flags2 & PSH_POINT_STRONG )
136 #define psh_point_is_fitted( p ) ( (p)->flags2 & PSH_POINT_FITTED )
137 #define psh_point_is_extremum( p ) ( (p)->flags2 & PSH_POINT_EXTREMUM )
138 #define psh_point_is_positive( p ) ( (p)->flags2 & PSH_POINT_POSITIVE )
139 #define psh_point_is_negative( p ) ( (p)->flags2 & PSH_POINT_NEGATIVE )
140 #define psh_point_is_edge_min( p ) ( (p)->flags2 & PSH_POINT_EDGE_MIN )
141 #define psh_point_is_edge_max( p ) ( (p)->flags2 & PSH_POINT_EDGE_MAX )
142
143 #define psh_point_set_strong( p ) (p)->flags2 |= PSH_POINT_STRONG
144 #define psh_point_set_fitted( p ) (p)->flags2 |= PSH_POINT_FITTED
145 #define psh_point_set_extremum( p ) (p)->flags2 |= PSH_POINT_EXTREMUM
146 #define psh_point_set_positive( p ) (p)->flags2 |= PSH_POINT_POSITIVE
147 #define psh_point_set_negative( p ) (p)->flags2 |= PSH_POINT_NEGATIVE
148 #define psh_point_set_edge_min( p ) (p)->flags2 |= PSH_POINT_EDGE_MIN
149 #define psh_point_set_edge_max( p ) (p)->flags2 |= PSH_POINT_EDGE_MAX
150
151
152 typedef struct PSH_PointRec_
153 {
154 PSH_Point prev;
155 PSH_Point next;
156 PSH_Contour contour;
157 FT_UInt flags;
158 FT_UInt flags2;
159 PSH_Dir dir_in;
160 PSH_Dir dir_out;
161 PSH_Hint hint;
162 FT_Pos org_u;
163 FT_Pos org_v;
164 FT_Pos cur_u;
165 #ifdef DEBUG_HINTER
166 FT_Pos org_x;
167 FT_Pos cur_x;
168 FT_Pos org_y;
169 FT_Pos cur_y;
170 FT_UInt flags_x;
171 FT_UInt flags_y;
172 #endif
173
174 } PSH_PointRec;
175
176
177 typedef struct PSH_ContourRec_
178 {
179 PSH_Point start;
180 FT_UInt count;
181
182 } PSH_ContourRec;
183
184
185 typedef struct PSH_GlyphRec_
186 {
187 FT_UInt num_points;
188 FT_UInt num_contours;
189
190 PSH_Point points;
191 PSH_Contour contours;
192
193 FT_Memory memory;
194 FT_Outline* outline;
195 PSH_Globals globals;
196 PSH_Hint_TableRec hint_tables[2];
197
198 FT_Bool do_horz_hints;
199 FT_Bool do_vert_hints;
200 FT_Bool do_horz_snapping;
201 FT_Bool do_vert_snapping;
202 FT_Bool do_stem_adjust;
203
204 } PSH_GlyphRec, *PSH_Glyph;
205
206
207 #ifdef DEBUG_HINTER
208 extern PSH_Hint_Table ps_debug_hint_table;
209
210 typedef void
211 (*PSH_HintFunc)( PSH_Hint hint,
212 FT_Bool vertical );
213
214 extern PSH_HintFunc ps_debug_hint_func;
215
216 extern PSH_Glyph ps_debug_glyph;
217 #endif
218
219
220 extern FT_Error
221 ps_hints_apply( PS_Hints ps_hints,
222 FT_Outline* outline,
223 PSH_Globals globals,
224 FT_Render_Mode hint_mode );
225
226
227 FT_END_HEADER
228
229
230 #endif /* PSHALGO_H_ */
231
232
233 /* END */