XFA: merge patch from CL 817753002
[pdfium.git] / core / src / fxge / fx_freetype / fxft2.5.01 / src / truetype / ttinterp.h
1 /***************************************************************************/
2 /*                                                                         */
3 /*  ttinterp.h                                                             */
4 /*                                                                         */
5 /*    TrueType bytecode interpreter (specification).                       */
6 /*                                                                         */
7 /*  Copyright 1996-2007, 2010, 2012-2013 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 __TTINTERP_H__
20 #define __TTINTERP_H__
21
22 #include "../../include/ft2build.h"
23 #include "ttobjs.h"
24
25
26 FT_BEGIN_HEADER
27
28
29 #ifndef TT_CONFIG_OPTION_STATIC_INTERPRETER /* indirect implementation */
30
31 #define EXEC_OP_   TT_ExecContext  exc,
32 #define EXEC_OP    TT_ExecContext  exc
33 #define EXEC_ARG_  exc,
34 #define EXEC_ARG   exc
35
36 #else                                       /* static implementation */
37
38 #define EXEC_OP_   /* void */
39 #define EXEC_OP    /* void */
40 #define EXEC_ARG_  /* void */
41 #define EXEC_ARG   /* void */
42
43 #endif /* TT_CONFIG_OPTION_STATIC_INTERPRETER */
44
45
46   /*************************************************************************/
47   /*                                                                       */
48   /* Rounding mode constants.                                              */
49   /*                                                                       */
50 #define TT_Round_Off             5
51 #define TT_Round_To_Half_Grid    0
52 #define TT_Round_To_Grid         1
53 #define TT_Round_To_Double_Grid  2
54 #define TT_Round_Up_To_Grid      4
55 #define TT_Round_Down_To_Grid    3
56 #define TT_Round_Super           6
57 #define TT_Round_Super_45        7
58
59
60   /*************************************************************************/
61   /*                                                                       */
62   /* Function types used by the interpreter, depending on various modes    */
63   /* (e.g. the rounding mode, whether to render a vertical or horizontal   */
64   /* line etc).                                                            */
65   /*                                                                       */
66   /*************************************************************************/
67
68   /* Rounding function */
69   typedef FT_F26Dot6
70   (*TT_Round_Func)( EXEC_OP_ FT_F26Dot6  distance,
71                              FT_F26Dot6  compensation );
72
73   /* Point displacement along the freedom vector routine */
74   typedef void
75   (*TT_Move_Func)( EXEC_OP_ TT_GlyphZone  zone,
76                             FT_UShort     point,
77                             FT_F26Dot6    distance );
78
79   /* Distance projection along one of the projection vectors */
80   typedef FT_F26Dot6
81   (*TT_Project_Func)( EXEC_OP_ FT_Pos   dx,
82                                FT_Pos   dy );
83
84   /* reading a cvt value.  Take care of non-square pixels if necessary */
85   typedef FT_F26Dot6
86   (*TT_Get_CVT_Func)( EXEC_OP_ FT_ULong  idx );
87
88   /* setting or moving a cvt value.  Take care of non-square pixels  */
89   /* if necessary                                                    */
90   typedef void
91   (*TT_Set_CVT_Func)( EXEC_OP_ FT_ULong    idx,
92                                FT_F26Dot6  value );
93
94
95   /*************************************************************************/
96   /*                                                                       */
97   /* This structure defines a call record, used to manage function calls.  */
98   /*                                                                       */
99   typedef struct  TT_CallRec_
100   {
101     FT_Int   Caller_Range;
102     FT_Long  Caller_IP;
103     FT_Long  Cur_Count;
104     FT_Long  Cur_Restart;
105     FT_Long  Cur_End;
106
107   } TT_CallRec, *TT_CallStack;
108
109
110 #ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
111
112   /*************************************************************************/
113   /*                                                                       */
114   /* These structures define rules used to tweak subpixel hinting for      */
115   /* various fonts.  "", 0, "", NULL value indicates to match any value.   */
116   /*                                                                       */
117
118 #define SPH_MAX_NAME_SIZE      32
119 #define SPH_MAX_CLASS_MEMBERS  100
120
121   typedef struct  SPH_TweakRule_
122   {
123     const char      family[SPH_MAX_NAME_SIZE];
124     const FT_UInt   ppem;
125     const char      style[SPH_MAX_NAME_SIZE];
126     const FT_ULong  glyph;
127
128   } SPH_TweakRule;
129
130
131   typedef struct  SPH_ScaleRule_
132   {
133     const char      family[SPH_MAX_NAME_SIZE];
134     const FT_UInt   ppem;
135     const char      style[SPH_MAX_NAME_SIZE];
136     const FT_ULong  glyph;
137     const FT_ULong  scale;
138
139   } SPH_ScaleRule;
140
141
142   typedef struct  SPH_Font_Class_
143   {
144     const char  name[SPH_MAX_NAME_SIZE];
145     const char  member[SPH_MAX_CLASS_MEMBERS][SPH_MAX_NAME_SIZE];
146
147   } SPH_Font_Class;
148
149 #endif /* TT_CONFIG_OPTION_SUBPIXEL_HINTING */
150
151
152   /*************************************************************************/
153   /*                                                                       */
154   /* The main structure for the interpreter which collects all necessary   */
155   /* variables and states.                                                 */
156   /*                                                                       */
157   typedef struct  TT_ExecContextRec_
158   {
159     TT_Face            face;
160     TT_Size            size;
161     FT_Memory          memory;
162
163     /* instructions state */
164
165     FT_Error           error;      /* last execution error */
166
167     FT_Long            top;        /* top of exec. stack   */
168
169     FT_UInt            stackSize;  /* size of exec. stack  */
170     FT_Long*           stack;      /* current exec. stack  */
171
172     FT_Long            args;
173     FT_UInt            new_top;    /* new top after exec.  */
174
175     TT_GlyphZoneRec    zp0,        /* zone records */
176                        zp1,
177                        zp2,
178                        pts,
179                        twilight;
180
181     FT_Size_Metrics    metrics;
182     TT_Size_Metrics    tt_metrics; /* size metrics */
183
184     TT_GraphicsState   GS;         /* current graphics state */
185
186     FT_Int             curRange;  /* current code range number   */
187     FT_Byte*           code;      /* current code range          */
188     FT_Long            IP;        /* current instruction pointer */
189     FT_Long            codeSize;  /* size of current range       */
190
191     FT_Byte            opcode;    /* current opcode              */
192     FT_Int             length;    /* length of current opcode    */
193
194     FT_Bool            step_ins;  /* true if the interpreter must */
195                                   /* increment IP after ins. exec */
196     FT_ULong           cvtSize;
197     FT_Long*           cvt;
198
199     FT_UInt            glyphSize; /* glyph instructions buffer size */
200     FT_Byte*           glyphIns;  /* glyph instructions buffer */
201
202     FT_UInt            numFDefs;  /* number of function defs         */
203     FT_UInt            maxFDefs;  /* maximum number of function defs */
204     TT_DefArray        FDefs;     /* table of FDefs entries          */
205
206     FT_UInt            numIDefs;  /* number of instruction defs */
207     FT_UInt            maxIDefs;  /* maximum number of ins defs */
208     TT_DefArray        IDefs;     /* table of IDefs entries     */
209
210     FT_UInt            maxFunc;   /* maximum function index     */
211     FT_UInt            maxIns;    /* maximum instruction index  */
212
213     FT_Int             callTop,    /* top of call stack during execution */
214                        callSize;   /* size of call stack */
215     TT_CallStack       callStack;  /* call stack */
216
217     FT_UShort          maxPoints;    /* capacity of this context's `pts' */
218     FT_Short           maxContours;  /* record, expressed in points and  */
219                                      /* contours.                        */
220
221     TT_CodeRangeTable  codeRangeTable;  /* table of valid code ranges */
222                                         /* useful for the debugger   */
223
224     FT_UShort          storeSize;  /* size of current storage */
225     FT_Long*           storage;    /* storage area            */
226
227     FT_F26Dot6         period;     /* values used for the */
228     FT_F26Dot6         phase;      /* `SuperRounding'     */
229     FT_F26Dot6         threshold;
230
231 #if 0
232     /* this seems to be unused */
233     FT_Int             cur_ppem;   /* ppem along the current proj vector */
234 #endif
235
236     FT_Bool            instruction_trap; /* If `True', the interpreter will */
237                                          /* exit after each instruction     */
238
239     TT_GraphicsState   default_GS;       /* graphics state resulting from   */
240                                          /* the prep program                */
241     FT_Bool            is_composite;     /* true if the glyph is composite  */
242     FT_Bool            pedantic_hinting; /* true if pedantic interpretation */
243
244     /* latest interpreter additions */
245
246     FT_Long            F_dot_P;    /* dot product of freedom and projection */
247                                    /* vectors                               */
248     TT_Round_Func      func_round; /* current rounding function             */
249
250     TT_Project_Func    func_project,   /* current projection function */
251                        func_dualproj,  /* current dual proj. function */
252                        func_freeProj;  /* current freedom proj. func  */
253
254     TT_Move_Func       func_move;      /* current point move function */
255     TT_Move_Func       func_move_orig; /* move original position function */
256
257     TT_Get_CVT_Func    func_read_cvt;  /* read a cvt entry              */
258     TT_Set_CVT_Func    func_write_cvt; /* write a cvt entry (in pixels) */
259     TT_Set_CVT_Func    func_move_cvt;  /* incr a cvt entry (in pixels)  */
260
261     FT_Bool            grayscale;      /* are we hinting for grayscale? */
262
263 #ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
264     TT_Round_Func      func_round_sphn;   /* subpixel rounding function */
265
266     FT_Bool            grayscale_hinting; /* Using grayscale hinting?      */
267     FT_Bool            subpixel_hinting;  /* Using subpixel hinting?       */
268     FT_Bool            native_hinting;    /* Using native hinting?         */
269     FT_Bool            ignore_x_mode;     /* Standard rendering mode for   */
270                                           /* subpixel hinting.  On if gray */
271                                           /* or subpixel hinting is on )   */
272
273     /* The following 4 aren't fully implemented but here for MS rasterizer */
274     /* compatibility.                                                      */
275     FT_Bool            compatible_widths;     /* compatible widths?        */
276     FT_Bool            symmetrical_smoothing; /* symmetrical_smoothing?    */
277     FT_Bool            bgr;                   /* bgr instead of rgb?       */
278     FT_Bool            subpixel_positioned;   /* subpixel positioned       */
279                                               /* (DirectWrite ClearType)?  */
280
281     FT_Int             rasterizer_version;    /* MS rasterizer version     */
282
283     FT_Bool            iup_called;            /* IUP called for glyph?     */
284
285     FT_ULong           sph_tweak_flags;       /* flags to control          */
286                                               /* hint tweaks               */
287
288     FT_ULong           sph_in_func_flags;     /* flags to indicate if in   */
289                                               /* special functions         */
290
291 #endif /* TT_CONFIG_OPTION_SUBPIXEL_HINTING */
292
293   } TT_ExecContextRec;
294
295
296   extern const TT_GraphicsState  tt_default_graphics_state;
297
298
299 #ifdef TT_USE_BYTECODE_INTERPRETER
300   FT_LOCAL( FT_Error )
301   TT_Goto_CodeRange( TT_ExecContext  exec,
302                      FT_Int          range,
303                      FT_Long         IP );
304
305   FT_LOCAL( FT_Error )
306   TT_Set_CodeRange( TT_ExecContext  exec,
307                     FT_Int          range,
308                     void*           base,
309                     FT_Long         length );
310
311   FT_LOCAL( FT_Error )
312   TT_Clear_CodeRange( TT_ExecContext  exec,
313                       FT_Int          range );
314
315
316   FT_LOCAL( FT_Error )
317   Update_Max( FT_Memory  memory,
318               FT_ULong*  size,
319               FT_Long    multiplier,
320               void*      _pbuff,
321               FT_ULong   new_max );
322 #endif /* TT_USE_BYTECODE_INTERPRETER */
323
324
325   /*************************************************************************/
326   /*                                                                       */
327   /* <Function>                                                            */
328   /*    TT_New_Context                                                     */
329   /*                                                                       */
330   /* <Description>                                                         */
331   /*    Queries the face context for a given font.  Note that there is     */
332   /*    now a _single_ execution context in the TrueType driver which is   */
333   /*    shared among faces.                                                */
334   /*                                                                       */
335   /* <Input>                                                               */
336   /*    face :: A handle to the source face object.                        */
337   /*                                                                       */
338   /* <Return>                                                              */
339   /*    A handle to the execution context.  Initialized for `face'.        */
340   /*                                                                       */
341   /* <Note>                                                                */
342   /*    Only the glyph loader and debugger should call this function.      */
343   /*                                                                       */
344   FT_EXPORT( TT_ExecContext )
345   TT_New_Context( TT_Driver  driver );
346
347
348 #ifdef TT_USE_BYTECODE_INTERPRETER
349   FT_LOCAL( FT_Error )
350   TT_Done_Context( TT_ExecContext  exec );
351
352   FT_LOCAL( FT_Error )
353   TT_Load_Context( TT_ExecContext  exec,
354                    TT_Face         face,
355                    TT_Size         size );
356
357   FT_LOCAL( FT_Error )
358   TT_Save_Context( TT_ExecContext  exec,
359                    TT_Size         ins );
360
361   FT_LOCAL( FT_Error )
362   TT_Run_Context( TT_ExecContext  exec,
363                   FT_Bool         debug );
364 #endif /* TT_USE_BYTECODE_INTERPRETER */
365
366
367   /*************************************************************************/
368   /*                                                                       */
369   /* <Function>                                                            */
370   /*    TT_RunIns                                                          */
371   /*                                                                       */
372   /* <Description>                                                         */
373   /*    Executes one or more instruction in the execution context.  This   */
374   /*    is the main function of the TrueType opcode interpreter.           */
375   /*                                                                       */
376   /* <Input>                                                               */
377   /*    exec :: A handle to the target execution context.                  */
378   /*                                                                       */
379   /* <Return>                                                              */
380   /*    FreeType error code.  0 means success.                             */
381   /*                                                                       */
382   /* <Note>                                                                */
383   /*    Only the object manager and debugger should call this function.    */
384   /*                                                                       */
385   /*    This function is publicly exported because it is directly          */
386   /*    invoked by the TrueType debugger.                                  */
387   /*                                                                       */
388   FT_EXPORT( FT_Error )
389   TT_RunIns( TT_ExecContext  exec );
390
391
392 FT_END_HEADER
393
394 #endif /* __TTINTERP_H__ */
395
396
397 /* END */